MOOD project is at the forefront of European research of infectious disease surveillance and modelling from a data science perspective, investigating the impact of global warming on disease outbreaks, and proposing innovations for building of One Health systems across Europe and the world.
In the table below are listed all MOOD publications. Use the filter to select the most relevant articles.
26.
Mencattelli, Giulia; Silverj, Andrea; Iapaolo, Federica; Ippoliti, Carla; Teodori, Liana; Di Gennaro, Annapia; Curini, Valentina; Candeloro, Luca; Conte, Annamaria; Polci, Andrea; Morelli, Daniela; Perrotta, Maria Gabriella; Marini, Giovanni; Rosà, Roberto; Monaco, Federica; Segata, Nicola; Rizzoli, Annapaola; Rota-Stabelli, Omar; Savini, Giovanni; Group, West Nile Working
Epidemiological and Evolutionary Analysis of West Nile Virus Lineage 2 in Italy Journal Article
In: Viruses, vol. 15, no. 35, 2022, ISSN: 1999-4915.
Abstract | Links | BibTeX | Tags: early-warning, epidemiology, evolution, Italy, West Nile virus lineage 2
@article{nokey,
title = {Epidemiological and Evolutionary Analysis of West Nile Virus Lineage 2 in Italy},
author = {Mencattelli, Giulia and Silverj, Andrea and Iapaolo, Federica and Ippoliti, Carla and Teodori, Liana and Di Gennaro, Annapia and Curini, Valentina and Candeloro, Luca and Conte, Annamaria and Polci, Andrea and Morelli, Daniela and Perrotta, Maria Gabriella and Marini, Giovanni and Rosà, Roberto and Monaco, Federica and Segata, Nicola and Rizzoli, Annapaola and Rota-Stabelli, Omar and Savini, Giovanni and West Nile Working Group},
url = {https://www.mdpi.com/1999-4915/15/1/35},
doi = {10.3390/v15010035},
issn = {1999-4915},
year = {2022},
date = {2022-12-22},
journal = {Viruses},
volume = {15},
number = {35},
abstract = {West Nile virus (WNV) is a mosquito-borne virus potentially causing serious illness in humans and other animals. Since 2004, several studies have highlighted the progressive spread of WNV Lineage 2 (L2) in Europe, with Italy being one of the countries with the highest number of cases of West Nile disease reported. In this paper, we give an overview of the epidemiological and genetic features characterising the spread and evolution of WNV L2 in Italy, leveraging data obtained from national surveillance activities between 2011 and 2021, including 46 newly assembled genomes that were analysed under both phylogeographic and phylodynamic frameworks. In addition, to better understand the seasonal patterns of the virus, we used a machine learning model predicting areas at high-risk of WNV spread. Our results show a progressive increase in WNV L2 in Italy, clarifying the dynamics of interregional circulation, with no significant introductions from other countries in recent years. Moreover, the predicting model identified the presence of suitable conditions for the 2022 earlier and wider spread of WNV in Italy, underlining the importance of using quantitative models for early warning detection of WNV outbreaks. Taken together, these findings can be used as a reference to develop new strategies to mitigate the impact of the pathogen on human and other animal health in endemic areas and new regions.},
keywords = {early-warning, epidemiology, evolution, Italy, West Nile virus lineage 2},
pubstate = {published},
tppubtype = {article}
}
West Nile virus (WNV) is a mosquito-borne virus potentially causing serious illness in humans and other animals. Since 2004, several studies have highlighted the progressive spread of WNV Lineage 2 (L2) in Europe, with Italy being one of the countries with the highest number of cases of West Nile disease reported. In this paper, we give an overview of the epidemiological and genetic features characterising the spread and evolution of WNV L2 in Italy, leveraging data obtained from national surveillance activities between 2011 and 2021, including 46 newly assembled genomes that were analysed under both phylogeographic and phylodynamic frameworks. In addition, to better understand the seasonal patterns of the virus, we used a machine learning model predicting areas at high-risk of WNV spread. Our results show a progressive increase in WNV L2 in Italy, clarifying the dynamics of interregional circulation, with no significant introductions from other countries in recent years. Moreover, the predicting model identified the presence of suitable conditions for the 2022 earlier and wider spread of WNV in Italy, underlining the importance of using quantitative models for early warning detection of WNV outbreaks. Taken together, these findings can be used as a reference to develop new strategies to mitigate the impact of the pathogen on human and other animal health in endemic areas and new regions.
25.
Brouazin, Ronan; Claudel, Iris; Lancelot, Renaud; Dupuy, Guillaume; Gouagna, Louis-Clément; Dupraz, Marlène; Baldet, Theirry; Bouyer, Jérémy
Optimization of oviposition trap settings to monitor populations of Aedes mosquitoes, vectors of arboviruses in La Reunion Journal Article
In: Nature Communications, iss. Sci Rep 12, no. 18450, 2022.
Abstract | Links | BibTeX | Tags: Animal behaviour, Ecology, Entomology, epidemiology
@article{nokey,
title = {Optimization of oviposition trap settings to monitor populations of Aedes mosquitoes, vectors of arboviruses in La Reunion},
author = {Ronan Brouazin and Iris Claudel and Renaud Lancelot and Guillaume Dupuy and Louis-Clément Gouagna and Marlène Dupraz and Theirry Baldet and Jérémy Bouyer},
url = {https://www.nature.com/articles/s41598-022-23137-5#citeas},
doi = {10.1038/s41598-022-23137-5},
year = {2022},
date = {2022-11-02},
urldate = {2022-11-02},
journal = {Nature Communications},
number = {18450},
issue = {Sci Rep 12},
abstract = {Several dengue epidemics recently occurred in La Reunion, an island harboring two dengue viruses (DVs) vectors: Aedes albopictus, and Ae. aegypti, the former being the main local DV vector. Aedes aegypti shows a peculiar ecology, compared to other tropical populations of the same species. This study aimed to provide researchers and public-health users with locally validated oviposition traps (ovitraps) to monitor Aedes populations. A field experiment was performed in Saint-Joseph to assess the effect of different settings on the detection probability and apparent density of Aedes mosquitoes. Black plastic ovitraps were identified as the best choice. Vacoa trees (Pandanus utilis) were the only observed breeding sites for Ae. aegypti, shared with Ae. albopictus. They were the experimental units in a Latin square design with three factors: trap position in the trees (ground vs canopy), oviposition surface in the trap (blotting paper vs. vacoa leaf), and addition of organic matter to the trap water. The latter factor was found unimportant. On the ground, Ae. aegypti eggs were only found with vacoa leaves as the oviposition surface. Their detection and apparent density increased when ovitraps were located in the tree canopy. The main factor for Ae. albopictus was the oviposition surface, with a preference for blotting paper. In all trap settings, their detection was close to 100%. Larval survival was lower for a high egg density, combined with blotting paper as the oviposition surface. When monitoring mixed Aedes populations in La Reunion, we recommend using black plastic ovitraps, placed at 1.50-to-2.00-m high in vacoa trees, with vacoa leaves as the oviposition surface.},
keywords = {Animal behaviour, Ecology, Entomology, epidemiology},
pubstate = {published},
tppubtype = {article}
}
Several dengue epidemics recently occurred in La Reunion, an island harboring two dengue viruses (DVs) vectors: Aedes albopictus, and Ae. aegypti, the former being the main local DV vector. Aedes aegypti shows a peculiar ecology, compared to other tropical populations of the same species. This study aimed to provide researchers and public-health users with locally validated oviposition traps (ovitraps) to monitor Aedes populations. A field experiment was performed in Saint-Joseph to assess the effect of different settings on the detection probability and apparent density of Aedes mosquitoes. Black plastic ovitraps were identified as the best choice. Vacoa trees (Pandanus utilis) were the only observed breeding sites for Ae. aegypti, shared with Ae. albopictus. They were the experimental units in a Latin square design with three factors: trap position in the trees (ground vs canopy), oviposition surface in the trap (blotting paper vs. vacoa leaf), and addition of organic matter to the trap water. The latter factor was found unimportant. On the ground, Ae. aegypti eggs were only found with vacoa leaves as the oviposition surface. Their detection and apparent density increased when ovitraps were located in the tree canopy. The main factor for Ae. albopictus was the oviposition surface, with a preference for blotting paper. In all trap settings, their detection was close to 100%. Larval survival was lower for a high egg density, combined with blotting paper as the oviposition surface. When monitoring mixed Aedes populations in La Reunion, we recommend using black plastic ovitraps, placed at 1.50-to-2.00-m high in vacoa trees, with vacoa leaves as the oviposition surface.
24.
Schaeffer, Camille; Interdonato, Roberto; Lancelot, Renaud; Roche, Mathieu; Teisseire, Maguelonne
Labeled entities from social media data related to avian influenza disease Journal Article Forthcoming
In: Data in Brief, vol. 43, pp. 108317, Forthcoming, ISSN: 2352-3409.
Abstract | Links | BibTeX | Tags: avian influenza, epidemiology, named entity recognition, OpenDataSet, social networks, Text mining
@article{@article{SCHAEFFER2022108317,,
title = {Labeled entities from social media data related to avian influenza disease},
author = {Schaeffer, Camille and Interdonato, Roberto and Lancelot, Renaud and Roche, Mathieu and Teisseire, Maguelonne},
url = {https://www.sciencedirect.com/science/article/pii/S2352340922005194},
doi = {https://doi.org/10.1016/j.dib.2022.108317},
issn = {2352-3409},
year = {2022},
date = {2022-08-01},
urldate = {2022-08-01},
journal = {Data in Brief},
volume = {43},
pages = {108317},
abstract = {This dataset is composed by spatial (e.g. location) and thematic (e.g. diseases, symptoms, virus) entities concerning avian influenza in social media (textual) data in English. It was created from three corpora: the first one includes 10 transcriptions of YouTube videos and 70 tweets manually annotated. The second corpus is composed by the same textual data but automatically annotated with Named Entity Recognition (NER) tools. These two corpora have been built to evaluate NER tools and apply them to a bigger corpus. The third corpus is composed of 100 YouTube transcriptions automatically annotated with NER tools. The aim of the annotation task is to recognize spatial information such as the names of the cities and epidemiological information such as the names of the diseases. An annotation guideline is provided in order to ensure a unified annotation and to help the annotators. This dataset can be used to train or evaluate Natural Language Processing (NLP) approaches such as specialized entity recognition.},
keywords = {avian influenza, epidemiology, named entity recognition, OpenDataSet, social networks, Text mining},
pubstate = {forthcoming},
tppubtype = {article}
}
This dataset is composed by spatial (e.g. location) and thematic (e.g. diseases, symptoms, virus) entities concerning avian influenza in social media (textual) data in English. It was created from three corpora: the first one includes 10 transcriptions of YouTube videos and 70 tweets manually annotated. The second corpus is composed by the same textual data but automatically annotated with Named Entity Recognition (NER) tools. These two corpora have been built to evaluate NER tools and apply them to a bigger corpus. The third corpus is composed of 100 YouTube transcriptions automatically annotated with NER tools. The aim of the annotation task is to recognize spatial information such as the names of the cities and epidemiological information such as the names of the diseases. An annotation guideline is provided in order to ensure a unified annotation and to help the annotators. This dataset can be used to train or evaluate Natural Language Processing (NLP) approaches such as specialized entity recognition.
23.
Agoti, Charles N; Ochola-Oyier, Lynette Isabella; Dellicour, Simon; Mohammed, Khadija Said; Lambisia, Arnold W; de Laurent, Zaydah R; Morobe, John M; Mburu, Maureen W; Omuoyo, Donwilliams O; Ongera, Edidah M; Ndwiga, Leonard; Maitha, Eric; Kitole, Benson; Suleiman, Thani; Mwakinangu, Mohamed; Nyambu, John K; Otieno, John; Salim, Barke; Musyoki, Jennifer; Murunga, Nickson; Otieno, Edward; Kiiru, John N; Kasera, Kadondi; Amoth, Patrick; Mwangangi, Mercy; Aman, Rashid; Kinyanjui, Samson; Warimwe, George; Phan, My; Agweyu, Ambrose; Cotten, Matthew; Barasa, Edwine; Tsofa, Benjamin; Nokes, D James; Bejon, Philip; Githinji, George
Transmission networks of SARS-CoV-2 in Coastal Kenya during the first two waves: A retrospective genomic study Journal Article
In: eLife, vol. 11, pp. e71703, 2022, ISSN: 2050-084X.
Abstract | Links | BibTeX | Tags: Africa, COVID-19, epidemiology, genome, transmission
@article{@article{10.7554/eLife.71703,
title = {Transmission networks of SARS-CoV-2 in Coastal Kenya during the first two waves: A retrospective genomic study},
author = {Agoti, Charles N and Ochola-Oyier, Lynette Isabella and Dellicour, Simon and Mohammed, Khadija Said and Lambisia, Arnold W and de Laurent, Zaydah R and Morobe, John M and Mburu, Maureen W and Omuoyo, Donwilliams O and Ongera, Edidah M and Ndwiga, Leonard and Maitha, Eric and Kitole, Benson and Suleiman, Thani and Mwakinangu, Mohamed and Nyambu, John K and Otieno, John and Salim, Barke and Musyoki, Jennifer and Murunga, Nickson and Otieno, Edward and Kiiru, John N and Kasera, Kadondi and Amoth, Patrick and Mwangangi, Mercy and Aman, Rashid and Kinyanjui, Samson and Warimwe, George and Phan, My and Agweyu, Ambrose and Cotten, Matthew and Barasa, Edwine and Tsofa, Benjamin and Nokes, D James and Bejon, Philip and Githinji, George},
editor = {Grabowski, Mary Kate and van der Meer, Jos W},},
url = {https://doi.org/10.7554/eLife.71703},
doi = {10.7554/eLife.71703},
issn = {2050-084X},
year = {2022},
date = {2022-06-14},
urldate = {2022-06-14},
journal = {eLife},
volume = {11},
pages = {e71703},
abstract = {Detailed understanding of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) regional transmission networks within sub-Saharan Africa is key for guiding local public health interventions against the pandemic. textbf{Methods:} Here, we analysed 1139 SARS-CoV-2 genomes from positive samples collected between March 2020 and February 2021 across six counties of Coastal Kenya (Mombasa, Kilifi, Taita Taveta, Kwale, Tana River, and Lamu) to infer virus introductions and local transmission patterns during the first two waves of infections. Virus importations were inferred using ancestral state reconstruction, and virus dispersal between counties was estimated using discrete phylogeographic analysis. textbf{Results:} During Wave 1, 23 distinct Pango lineages were detected across the six counties, while during Wave 2, 29 lineages were detected; 9 of which occurred in both waves and 4 seemed to be Kenya specific (B.1.530, B.1.549, B.1.596.1, and N.8). Most of the sequenced infections belonged to lineage B.1 (n = 723, 63%), which predominated in both Wave 1 (73%, followed by lineages N.8 [6%] and B.1.1 [6%]) and Wave 2 (56%, followed by lineages B.1.549 [21%] and B.1.530 [5%]). Over the study period, we estimated 280 SARS-CoV-2 virus importations into Coastal Kenya. Mombasa City, a vital tourist and commercial centre for the region, was a major route for virus imports, most of which occurred during Wave 1, when many Coronavirus Disease 2019 (COVID-19) government restrictions were still in force. In Wave 2, inter-county transmission predominated, resulting in the emergence of local transmission chains and diversity. textbf{Conclusions:} Our analysis supports moving COVID-19 control strategies in the region from a focus on international travel to strategies that will reduce local transmission. textbf{Funding:} This work was funded by The Wellcome (grant numbers: 220985, 203077/Z/16/Z, 220977/Z/20/Z, and 222574/Z/21/Z) and the National Institute for Health and Care Research (NIHR), project references: 17/63/and 16/136/33 using UK Aid from the UK government to support global health research, The UK Foreign, Commonwealth and Development Office. The views expressed in this publication are those of the author(s) and not necessarily those of the funding agencies.},},
keywords = {Africa, COVID-19, epidemiology, genome, transmission},
pubstate = {published},
tppubtype = {article}
}
Detailed understanding of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) regional transmission networks within sub-Saharan Africa is key for guiding local public health interventions against the pandemic. textbf{Methods:} Here, we analysed 1139 SARS-CoV-2 genomes from positive samples collected between March 2020 and February 2021 across six counties of Coastal Kenya (Mombasa, Kilifi, Taita Taveta, Kwale, Tana River, and Lamu) to infer virus introductions and local transmission patterns during the first two waves of infections. Virus importations were inferred using ancestral state reconstruction, and virus dispersal between counties was estimated using discrete phylogeographic analysis. textbf{Results:} During Wave 1, 23 distinct Pango lineages were detected across the six counties, while during Wave 2, 29 lineages were detected; 9 of which occurred in both waves and 4 seemed to be Kenya specific (B.1.530, B.1.549, B.1.596.1, and N.8). Most of the sequenced infections belonged to lineage B.1 (n = 723, 63%), which predominated in both Wave 1 (73%, followed by lineages N.8 [6%] and B.1.1 [6%]) and Wave 2 (56%, followed by lineages B.1.549 [21%] and B.1.530 [5%]). Over the study period, we estimated 280 SARS-CoV-2 virus importations into Coastal Kenya. Mombasa City, a vital tourist and commercial centre for the region, was a major route for virus imports, most of which occurred during Wave 1, when many Coronavirus Disease 2019 (COVID-19) government restrictions were still in force. In Wave 2, inter-county transmission predominated, resulting in the emergence of local transmission chains and diversity. textbf{Conclusions:} Our analysis supports moving COVID-19 control strategies in the region from a focus on international travel to strategies that will reduce local transmission. textbf{Funding:} This work was funded by The Wellcome (grant numbers: 220985, 203077/Z/16/Z, 220977/Z/20/Z, and 222574/Z/21/Z) and the National Institute for Health and Care Research (NIHR), project references: 17/63/and 16/136/33 using UK Aid from the UK government to support global health research, The UK Foreign, Commonwealth and Development Office. The views expressed in this publication are those of the author(s) and not necessarily those of the funding agencies.},
22.
Yong; Zhang Ge, Wen-Bin; Wu
Untangling the changing impact of non-pharmaceutical interventions and vaccination on European COVID-19 trajectories Journal Article
In: Nature Commun, vol. 13, no. 3106, 2022.
Abstract | Links | BibTeX | Tags: Applied mathematics, epidemiology, infectious diseases
@article{nokey,
title = {Untangling the changing impact of non-pharmaceutical interventions and vaccination on European COVID-19 trajectories},
author = {Ge, Yong; Zhang, Wen-Bin; Wu, Xilin; W Ruktanonchai, Corrine; Liu, Haiyan; Wang, Jianghao; Song, Yongze; Liu, Mengxiao; Yan, Wei; Yang, Juan; Cleary, Eimear; H Qader, Sarchil; Atuhaire, Fatumah; W Ruktanonchai, Nick; J Tatem, Andrew; Lai, Shengjie},
url = {https://www.nature.com/articles/s41467-022-30897-1#citeas},
doi = {10.1038/s41467-022-30897-1},
year = {2022},
date = {2022-06-03},
urldate = {2022-06-03},
journal = {Nature Commun},
volume = {13},
number = {3106},
abstract = {Non-pharmaceutical interventions (NPIs) and vaccination are two fundamental approaches for mitigating the coronavirus disease 2019 (COVID-19) pandemic. However, the real-world impact of NPIs versus vaccination, or a combination of both, on COVID-19 remains uncertain. To address this, we built a Bayesian inference model to assess the changing effect of NPIs and vaccination on reducing COVID-19 transmission, based on a large-scale dataset including epidemiological parameters, virus variants, vaccines, and climate factors in Europe from August 2020 to October 2021. We found that (1) the combined effect of NPIs and vaccination resulted in a 53% (95% confidence interval: 42–62%) reduction in reproduction number by October 2021, whereas NPIs and vaccination reduced the transmission by 35% and 38%, respectively; (2) compared with vaccination, the change of NPI effect was less sensitive to emerging variants; (3) the relative effect of NPIs declined 12% from May 2021 due to a lower stringency and the introduction of vaccination strategies. Our results demonstrate that NPIs were complementary to vaccination in an effort to reduce COVID-19 transmission, and the relaxation of NPIs might depend on vaccination rates, control targets, and vaccine effectiveness concerning extant and emerging variants.},
keywords = {Applied mathematics, epidemiology, infectious diseases},
pubstate = {published},
tppubtype = {article}
}
Non-pharmaceutical interventions (NPIs) and vaccination are two fundamental approaches for mitigating the coronavirus disease 2019 (COVID-19) pandemic. However, the real-world impact of NPIs versus vaccination, or a combination of both, on COVID-19 remains uncertain. To address this, we built a Bayesian inference model to assess the changing effect of NPIs and vaccination on reducing COVID-19 transmission, based on a large-scale dataset including epidemiological parameters, virus variants, vaccines, and climate factors in Europe from August 2020 to October 2021. We found that (1) the combined effect of NPIs and vaccination resulted in a 53% (95% confidence interval: 42–62%) reduction in reproduction number by October 2021, whereas NPIs and vaccination reduced the transmission by 35% and 38%, respectively; (2) compared with vaccination, the change of NPI effect was less sensitive to emerging variants; (3) the relative effect of NPIs declined 12% from May 2021 due to a lower stringency and the introduction of vaccination strategies. Our results demonstrate that NPIs were complementary to vaccination in an effort to reduce COVID-19 transmission, and the relaxation of NPIs might depend on vaccination rates, control targets, and vaccine effectiveness concerning extant and emerging variants.
21.
Viana, Raquel; Moyo, Sikhulile; Amoako, Daniel G; Tegally, Houriiyah; Scheepers, Cathrine; Althaus, Christian L; Anyaneji, Ugochukwu J; Bester, Phillip A; Boni, Maciej F; Chand, Mohammed; others,
Rapid epidemic expansion of the SARS-CoV-2 Omicron variant in southern Africa Journal Article
In: Nature, vol. 603, no. 7902, pp. 679-686, 2022.
Abstract | Links | BibTeX | Tags: epidemiology, Molecular evolution, SARS-CoV-2
@article{nokey,
title = {Rapid epidemic expansion of the SARS-CoV-2 Omicron variant in southern Africa},
author = {Viana, Raquel and Moyo, Sikhulile and Amoako, Daniel G and Tegally, Houriiyah and Scheepers, Cathrine and Althaus, Christian L and Anyaneji, Ugochukwu J and Bester, Phillip A and Boni, Maciej F and Chand, Mohammed and others},
url = {https://www.nature.com/articles/s41586-022-04411-y#citeas},
doi = {10.1038/s41586-022-04411-y},
year = {2022},
date = {2022-01-07},
journal = {Nature},
volume = {603},
number = {7902},
pages = {679-686},
abstract = {The SARS-CoV-2 epidemic in southern Africa has been characterized by three distinct waves. The first was associated with a mix of SARS-CoV-2 lineages, while the second and third waves were driven by the Beta (B.1.351) and Delta (B.1.617.2) variants, respectively1,2,3. In November 2021, genomic surveillance teams in South Africa and Botswana detected a new SARS-CoV-2 variant associated with a rapid resurgence of infections in Gauteng province, South Africa. Within three days of the first genome being uploaded, it was designated a variant of concern (Omicron, B.1.1.529) by the World Health Organization and, within three weeks, had been identified in 87 countries. The Omicron variant is exceptional for carrying over 30 mutations in the spike glycoprotein, which are predicted to influence antibody neutralization and spike function4. Here we describe the genomic profile and early transmission dynamics of Omicron, highlighting the rapid spread in regions with high levels of population immunity.},
keywords = {epidemiology, Molecular evolution, SARS-CoV-2},
pubstate = {published},
tppubtype = {article}
}
The SARS-CoV-2 epidemic in southern Africa has been characterized by three distinct waves. The first was associated with a mix of SARS-CoV-2 lineages, while the second and third waves were driven by the Beta (B.1.351) and Delta (B.1.617.2) variants, respectively1,2,3. In November 2021, genomic surveillance teams in South Africa and Botswana detected a new SARS-CoV-2 variant associated with a rapid resurgence of infections in Gauteng province, South Africa. Within three days of the first genome being uploaded, it was designated a variant of concern (Omicron, B.1.1.529) by the World Health Organization and, within three weeks, had been identified in 87 countries. The Omicron variant is exceptional for carrying over 30 mutations in the spike glycoprotein, which are predicted to influence antibody neutralization and spike function4. Here we describe the genomic profile and early transmission dynamics of Omicron, highlighting the rapid spread in regions with high levels of population immunity.
20.
Cereda, Danilo; Manica, Mattia; Tirani, Marcello; Rovida, Francesca; Demicheli, Vittorio; Ajelli, Marco; Poletti, Piero; Trentini, Filippo; Guzzetta, Giorgio; Marziano, Valentina; Piccarreta, Raffaella; Barone, Antonio; Magoni, Michele; Deandrea, Silvia; Diurno, Giulio; Lombardo, Massimo; Faccini, Marino; Pan, Angelo; Bruno, Raffaele; Pariani, Elena; Grasselli, Giacomo; Piatti, Alessandra; Gramegna, Maria; Baldanti, Fausto; Melegaro, Alessia; Merler, Stefano
The early phase of the COVID-19 epidemic in Lombardy, Italy Journal Article
In: Epidemics, vol. 37, pp. 100528, 2021, ISSN: 1755-4365.
Abstract | Links | BibTeX | Tags: Coronavirus, COVID-19, epidemiology, Lombardy outbreak, reproduction number, SARS-CoV-2, Transmission dynamics
@article{@article{CEREDA2021100528,,
title = {The early phase of the COVID-19 epidemic in Lombardy, Italy},
author = {Danilo Cereda and Mattia Manica and Marcello Tirani and Francesca Rovida and Vittorio Demicheli and Marco Ajelli and Piero Poletti and Filippo Trentini and Giorgio Guzzetta and Valentina Marziano and Raffaella Piccarreta and Antonio Barone and Michele Magoni and Silvia Deandrea and Giulio Diurno and Massimo Lombardo and Marino Faccini and Angelo Pan and Raffaele Bruno and Elena Pariani and Giacomo Grasselli and Alessandra Piatti and Maria Gramegna and Fausto Baldanti and Alessia Melegaro and Stefano Merler},
url = {https://www.sciencedirect.com/science/article/pii/S1755436521000724},
doi = {https://doi.org/10.1016/j.epidem.2021.100528},
issn = {1755-4365},
year = {2021},
date = {2021-12-01},
urldate = {2021-12-01},
journal = {Epidemics},
volume = {37},
pages = {100528},
abstract = {Background
In the night of February 20, 2020, the first epidemic of the novel coronavirus disease (COVID-19) outside Asia was uncovered by the identification of its first patient in Lombardy region, Italy. In the following weeks, Lombardy experienced a sudden increase in the number of ascertained infections and strict measures were imposed to contain the epidemic spread.
Methods
We analyzed official records of cases occurred in Lombardy to characterize the epidemiology of SARS-CoV-2 during the early phase of the outbreak. A line list of laboratory-confirmed cases was set up and later retrospectively consolidated, using standardized interviews to ascertained cases and their close contacts. We provide estimates of the serial interval, of the basic reproduction number, and of the temporal variation of the net reproduction number of SARS-CoV-2.
Results
Epidemiological investigations detected over 500 cases (median age: 69, IQR: 57–78) before the first COVID-19 diagnosed patient (February 20, 2020), and suggested that SARS-CoV-2 was already circulating in at least 222 out of 1506 (14.7%) municipalities with sustained transmission across all the Lombardy provinces. We estimated the mean serial interval to be 6.6 days (95% CrI, 0.7–19). Our estimates of the basic reproduction number range from 2.6 in Pavia (95% CI, 2.1–3.2) to 3.3 in Milan (95% CI, 2.9–3.8). A decreasing trend in the net reproduction number was observed following the detection of the first case.
Conclusions
At the time of first case notification, COVID-19 was already widespread in the entire Lombardy region. This may explain the large number of critical cases experienced by this region in a very short timeframe. The slight decrease of the reproduction number observed in the early days after February 20, 2020 might be due to increased population awareness and early interventions implemented before the regional lockdown imposed on March 8, 2020.},
keywords = {Coronavirus, COVID-19, epidemiology, Lombardy outbreak, reproduction number, SARS-CoV-2, Transmission dynamics},
pubstate = {published},
tppubtype = {article}
}
Background
In the night of February 20, 2020, the first epidemic of the novel coronavirus disease (COVID-19) outside Asia was uncovered by the identification of its first patient in Lombardy region, Italy. In the following weeks, Lombardy experienced a sudden increase in the number of ascertained infections and strict measures were imposed to contain the epidemic spread.
Methods
We analyzed official records of cases occurred in Lombardy to characterize the epidemiology of SARS-CoV-2 during the early phase of the outbreak. A line list of laboratory-confirmed cases was set up and later retrospectively consolidated, using standardized interviews to ascertained cases and their close contacts. We provide estimates of the serial interval, of the basic reproduction number, and of the temporal variation of the net reproduction number of SARS-CoV-2.
Results
Epidemiological investigations detected over 500 cases (median age: 69, IQR: 57–78) before the first COVID-19 diagnosed patient (February 20, 2020), and suggested that SARS-CoV-2 was already circulating in at least 222 out of 1506 (14.7%) municipalities with sustained transmission across all the Lombardy provinces. We estimated the mean serial interval to be 6.6 days (95% CrI, 0.7–19). Our estimates of the basic reproduction number range from 2.6 in Pavia (95% CI, 2.1–3.2) to 3.3 in Milan (95% CI, 2.9–3.8). A decreasing trend in the net reproduction number was observed following the detection of the first case.
Conclusions
At the time of first case notification, COVID-19 was already widespread in the entire Lombardy region. This may explain the large number of critical cases experienced by this region in a very short timeframe. The slight decrease of the reproduction number observed in the early days after February 20, 2020 might be due to increased population awareness and early interventions implemented before the regional lockdown imposed on March 8, 2020.
In the night of February 20, 2020, the first epidemic of the novel coronavirus disease (COVID-19) outside Asia was uncovered by the identification of its first patient in Lombardy region, Italy. In the following weeks, Lombardy experienced a sudden increase in the number of ascertained infections and strict measures were imposed to contain the epidemic spread.
Methods
We analyzed official records of cases occurred in Lombardy to characterize the epidemiology of SARS-CoV-2 during the early phase of the outbreak. A line list of laboratory-confirmed cases was set up and later retrospectively consolidated, using standardized interviews to ascertained cases and their close contacts. We provide estimates of the serial interval, of the basic reproduction number, and of the temporal variation of the net reproduction number of SARS-CoV-2.
Results
Epidemiological investigations detected over 500 cases (median age: 69, IQR: 57–78) before the first COVID-19 diagnosed patient (February 20, 2020), and suggested that SARS-CoV-2 was already circulating in at least 222 out of 1506 (14.7%) municipalities with sustained transmission across all the Lombardy provinces. We estimated the mean serial interval to be 6.6 days (95% CrI, 0.7–19). Our estimates of the basic reproduction number range from 2.6 in Pavia (95% CI, 2.1–3.2) to 3.3 in Milan (95% CI, 2.9–3.8). A decreasing trend in the net reproduction number was observed following the detection of the first case.
Conclusions
At the time of first case notification, COVID-19 was already widespread in the entire Lombardy region. This may explain the large number of critical cases experienced by this region in a very short timeframe. The slight decrease of the reproduction number observed in the early days after February 20, 2020 might be due to increased population awareness and early interventions implemented before the regional lockdown imposed on March 8, 2020.
19.
Pullano, Giulia; Domenico, Laura Di; Colizza, Vittoria
Telework and other measures reducing the presence at work to slow down COVID-19pdm in France (Sept 2020) Technical Report
2021.
Abstract | Links | BibTeX | Tags: COVID-19, epidemiology, France, measures
@techreport{nokey,
title = {Telework and other measures reducing the presence at work to slow down COVID-19pdm in France (Sept 2020)},
author = {Giulia Pullano and Laura Di Domenico and Vittoria Colizza},
url = {http://www.epicx-lab.com/uploads/9/6/9/4/9694133/inserm_covid-19-telework.pdf},
year = {2021},
date = {2021-11-28},
abstract = {COVID-19 pandemic shows a clear and substantial increase of activity in France since summer 2020.
Certain regions are in highly vulnerable situations, with large number of hospitalizations per day,
important fraction of ICU beds occupied, and short doubling times (<2 weeks). At the same time,
activities are increasing since the beginning of September, with the reopening of schools and the return
to work after summer holidays (not yet reaching pre-pandemic levels), leaving further opportunities for
the virus to spread. Using mathematical models calibrated to the observed epidemic trajectory in each
region, this report analyzes possible scenarios of telework and other means to reduce the presence at
work, and assesses their impact on the epidemic trajectory in the following weeks. Numerical results
confirm that telework and other measures reducing the presence at work under realistic assumptions
may decelerate the epidemic curve gaining few weeks of time, but would not be enough to revert the
increasing tendency of the curve, unless coupled with other contact reduction measures. The situation is
particularly critical in IDF. In these conditions, if nothing changes, the level of hospitalizations of the peak
of the first wave is expected to be reached in IDF in about a month from now (earlier, if return to work
increases in the following weeks as suggested by the trend in the data and if not contrasted by telework).
Explicit guidance on telework and interventions to facilitate its application to all professional categories
who can adopt it should be urgently provided. This standard should be kept as a routine measure of
epidemic control for several months. More restrictive measures involving the closure of certain activities
to reduce avoidable contacts are urgently needed to slow down the epidemic increase to levels that are
manageable by the healthcare system. This analysis cannot account for the effect of the measures
implemented today},
keywords = {COVID-19, epidemiology, France, measures},
pubstate = {published},
tppubtype = {techreport}
}
COVID-19 pandemic shows a clear and substantial increase of activity in France since summer 2020.
Certain regions are in highly vulnerable situations, with large number of hospitalizations per day,
important fraction of ICU beds occupied, and short doubling times (<2 weeks). At the same time,
activities are increasing since the beginning of September, with the reopening of schools and the return
to work after summer holidays (not yet reaching pre-pandemic levels), leaving further opportunities for
the virus to spread. Using mathematical models calibrated to the observed epidemic trajectory in each
region, this report analyzes possible scenarios of telework and other means to reduce the presence at
work, and assesses their impact on the epidemic trajectory in the following weeks. Numerical results
confirm that telework and other measures reducing the presence at work under realistic assumptions
may decelerate the epidemic curve gaining few weeks of time, but would not be enough to revert the
increasing tendency of the curve, unless coupled with other contact reduction measures. The situation is
particularly critical in IDF. In these conditions, if nothing changes, the level of hospitalizations of the peak
of the first wave is expected to be reached in IDF in about a month from now (earlier, if return to work
increases in the following weeks as suggested by the trend in the data and if not contrasted by telework).
Explicit guidance on telework and interventions to facilitate its application to all professional categories
who can adopt it should be urgently provided. This standard should be kept as a routine measure of
epidemic control for several months. More restrictive measures involving the closure of certain activities
to reduce avoidable contacts are urgently needed to slow down the epidemic increase to levels that are
manageable by the healthcare system. This analysis cannot account for the effect of the measures
implemented today
Certain regions are in highly vulnerable situations, with large number of hospitalizations per day,
important fraction of ICU beds occupied, and short doubling times (<2 weeks). At the same time,
activities are increasing since the beginning of September, with the reopening of schools and the return
to work after summer holidays (not yet reaching pre-pandemic levels), leaving further opportunities for
the virus to spread. Using mathematical models calibrated to the observed epidemic trajectory in each
region, this report analyzes possible scenarios of telework and other means to reduce the presence at
work, and assesses their impact on the epidemic trajectory in the following weeks. Numerical results
confirm that telework and other measures reducing the presence at work under realistic assumptions
may decelerate the epidemic curve gaining few weeks of time, but would not be enough to revert the
increasing tendency of the curve, unless coupled with other contact reduction measures. The situation is
particularly critical in IDF. In these conditions, if nothing changes, the level of hospitalizations of the peak
of the first wave is expected to be reached in IDF in about a month from now (earlier, if return to work
increases in the following weeks as suggested by the trend in the data and if not contrasted by telework).
Explicit guidance on telework and interventions to facilitate its application to all professional categories
who can adopt it should be urgently provided. This standard should be kept as a routine measure of
epidemic control for several months. More restrictive measures involving the closure of certain activities
to reduce avoidable contacts are urgently needed to slow down the epidemic increase to levels that are
manageable by the healthcare system. This analysis cannot account for the effect of the measures
implemented today
18.
Kraemer, Moritz U. G.; Fraser, Oliver G. Pybusand; Cauchemez, Christophe; Rambaut, Simon; Cowling, Andrew; Benjamin, J.
Monitoring key epidemiological parameters of SARS-CoV-2 transmission Journal Article
In: Nature Medicine, vol. 27, no. 1854–1855 , pp. 1–2, 2021.
Abstract | Links | BibTeX | Tags: COVID-19, epidemiology, transmission
@article{kraemer2021monitoring,
title = {Monitoring key epidemiological parameters of SARS-CoV-2 transmission},
author = {Moritz U.G. Kraemer and Oliver G. Pybusand Fraser and Christophe Cauchemez and Simon Rambaut and Andrew Cowling and J. Benjamin},
doi = {https://doi.org/10.1038/s41591-021-01545-w},
year = {2021},
date = {2021-11-08},
urldate = {2021-11-08},
journal = {Nature Medicine},
volume = {27},
number = {1854–1855 },
pages = {1--2},
abstract = {Control of the SARS-CoV-2 pandemic requires targeted interventions, which in turn require precise estimates of quantities that describe transmission. Per-capita transmission rates are influenced by four quantities: (1) the latent period (time from infection to becoming infectious); (2) individual variability in infectiousness (defined by variation in intrinsic transmissibility and contact rate); (3) the incubation period (time from infection to symptom onset); and (4) the serial interval (time between symptom onset of an infector and an infected) (Fig. 1).},
keywords = {COVID-19, epidemiology, transmission},
pubstate = {published},
tppubtype = {article}
}
Control of the SARS-CoV-2 pandemic requires targeted interventions, which in turn require precise estimates of quantities that describe transmission. Per-capita transmission rates are influenced by four quantities: (1) the latent period (time from infection to becoming infectious); (2) individual variability in infectiousness (defined by variation in intrinsic transmissibility and contact rate); (3) the incubation period (time from infection to symptom onset); and (4) the serial interval (time between symptom onset of an infector and an infected) (Fig. 1).
17.
Faria, Nuno R.; Mellan, Thomas A.; Whittaker, Charles; Claro, Ingra M.; da S. Candido, Darlan; Mishra, Swapnil; Crispim, Myuki A. E.
Genomics and epidemiology of the P.1 SARS-CoV-2 lineage in Manaus, Brazil Journal Article
In: Science, vol. 372, no. 6544, pp. 815-821, 2021.
Abstract | Links | BibTeX | Tags: Brazil, COVID-19, epidemiology, OpenDataSet, phylogenetic
@article{nokey,
title = {Genomics and epidemiology of the P.1 SARS-CoV-2 lineage in Manaus, Brazil},
author = {Nuno R. Faria and Thomas A. Mellan and Charles Whittaker and Ingra M. Claro and Darlan da S. Candido and Swapnil Mishra and Myuki A. E. Crispim},
url = {https://www.science.org/doi/abs/10.1126/science.abh2644},
doi = {10.1126/science.abh2644},
year = {2021},
date = {2021-11-01},
urldate = {2021-11-01},
journal = {Science},
volume = {372},
number = {6544},
pages = {815-821},
abstract = {Cases of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in Manaus, Brazil, resurged in late 2020 despite previously high levels of infection. Genome sequencing of viruses sampled in Manaus between November 2020 and January 2021 revealed the emergence and circulation of a novel SARS-CoV-2 variant of concern. Lineage P.1 acquired 17 mutations, including a trio in the spike protein (K417T, E484K, and N501Y) associated with increased binding to the human ACE2 (angiotensin-converting enzyme 2) receptor. Molecular clock analysis shows that P.1 emergence occurred around mid-November 2020 and was preceded by a period of faster molecular evolution. Using a two-category dynamical model that integrates genomic and mortality data, we estimate that P.1 may be 1.7- to 2.4-fold more transmissible and that previous (non-P.1) infection provides 54 to 79% of the protection against infection with P.1 that it provides against non-P.1 lineages. Enhanced global genomic surveillance of variants of concern, which may exhibit increased transmissibility and/or immune evasion, is critical to accelerate pandemic responsiveness.},
keywords = {Brazil, COVID-19, epidemiology, OpenDataSet, phylogenetic},
pubstate = {published},
tppubtype = {article}
}
Cases of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in Manaus, Brazil, resurged in late 2020 despite previously high levels of infection. Genome sequencing of viruses sampled in Manaus between November 2020 and January 2021 revealed the emergence and circulation of a novel SARS-CoV-2 variant of concern. Lineage P.1 acquired 17 mutations, including a trio in the spike protein (K417T, E484K, and N501Y) associated with increased binding to the human ACE2 (angiotensin-converting enzyme 2) receptor. Molecular clock analysis shows that P.1 emergence occurred around mid-November 2020 and was preceded by a period of faster molecular evolution. Using a two-category dynamical model that integrates genomic and mortality data, we estimate that P.1 may be 1.7- to 2.4-fold more transmissible and that previous (non-P.1) infection provides 54 to 79% of the protection against infection with P.1 that it provides against non-P.1 lineages. Enhanced global genomic surveillance of variants of concern, which may exhibit increased transmissibility and/or immune evasion, is critical to accelerate pandemic responsiveness.
16.
Domenico, Laura Di; Sabbatini, Chiara E.; Pullano, Giulia; Lévy-Bruhl, Daniel; Colizza, Vittoria
Impact of January 2021 curfew measures on SARS-CoV-2 B.1.1.7 circulation in France Journal Article
In: Eurosurveillance, vol. 26, iss. 15, no. 2, 2021.
Abstract | Links | BibTeX | Tags: COVID-19, epidemiology, Europe, Public Health
@article{,
title = {Impact of January 2021 curfew measures on SARS-CoV-2 B.1.1.7 circulation in France},
author = {Laura Di Domenico and Chiara E. Sabbatini and Giulia Pullano and Daniel Lévy-Bruhl and Vittoria Colizza},
url = {https://www.eurosurveillance.org/content/10.2807/1560-7917.ES.2021.26.15.2100272},
doi = { 10.2807/1560-7917.ES.2021.26.15.2100272},
year = {2021},
date = {2021-04-15},
urldate = {2021-03-10},
journal = {Eurosurveillance},
volume = {26},
number = {2},
issue = {15},
publisher = {Cold Spring Harbor Laboratory Press},
abstract = {Facing B.1.1.7 variant, social distancing was strengthened in France in January 2021. Using a 2-strain mathematical model calibrated on genomic surveillance, we estimated that curfew measures allowed hospitalizations to plateau, by decreasing transmission of the historical strain while B.1.1.7 continued to grow. School holidays appear to have further slowed down progression in February. Without progressively strengthened social distancing, a rapid surge of hospitalizations is expected, despite the foreseen increase in vaccination rhythm.},
keywords = {COVID-19, epidemiology, Europe, Public Health},
pubstate = {published},
tppubtype = {article}
}
Facing B.1.1.7 variant, social distancing was strengthened in France in January 2021. Using a 2-strain mathematical model calibrated on genomic surveillance, we estimated that curfew measures allowed hospitalizations to plateau, by decreasing transmission of the historical strain while B.1.1.7 continued to grow. School holidays appear to have further slowed down progression in February. Without progressively strengthened social distancing, a rapid surge of hospitalizations is expected, despite the foreseen increase in vaccination rhythm.
15.
Huang, Bo; Wang, Jionghua; Cai, Jixuan; Yao, Shiqi; Chan, Paul Kay Sheung; Tam, Tony Hong-wing; Hong, Ying-Yi; Ruktanonchai, Corrine W.; Carioli, Alessandra; Floyd, Jessica R.; Ruktanonchai, Nick W.; Yang, Weizhong; Li, Zhongjie; Tatem, Andrew J.; Lai, Shengjie
Integrated vaccination and physical distancing interventions to prevent future COVID-19 waves in Chinese cities Journal Article
In: Nature Human Behaviour, vol. 5, pp. 695–705, 2021.
Abstract | Links | BibTeX | Tags: China, COVID-19, epidemiology, OpenDataSet, vaccine
@article{nokey,
title = {Integrated vaccination and physical distancing interventions to prevent future COVID-19 waves in Chinese cities},
author = {Bo Huang and Jionghua Wang and Jixuan Cai and Shiqi Yao and Paul Kay Sheung Chan and Tony Hong-wing Tam and Ying-Yi Hong and Corrine W. Ruktanonchai and Alessandra Carioli and Jessica R. Floyd and Nick W. Ruktanonchai and Weizhong Yang and Zhongjie Li and Andrew J. Tatem and Shengjie Lai },
doi = {https://doi.org/10.1038/s41562-021-01063-2},
year = {2021},
date = {2021-02-18},
urldate = {2021-02-18},
journal = {Nature Human Behaviour},
volume = {5},
pages = {695–705},
abstract = {The coronavirus disease 2019 (COVID-19) pandemic has posed substantial challenges to the formulation of preventive interventions, particularly since the effects of physical distancing measures and upcoming vaccines on reducing susceptible social contacts and eventually halting transmission remain unclear. Here, using anonymized mobile geolocation data in China, we devise a mobility-associated social contact index to quantify the impact of both physical distancing and vaccination measures in a unified way. Building on this index, our epidemiological model reveals that vaccination combined with physical distancing can contain resurgences without relying on stay-at-home restrictions, whereas a gradual vaccination process alone cannot achieve this. Further, for cities with medium population density, vaccination can reduce the duration of physical distancing by 36% to 78%, whereas for cities with high population density, infection numbers can be well-controlled through moderate physical distancing. These findings improve our understanding of the joint effects of vaccination and physical distancing with respect to a city’s population density and social contact patterns.},
keywords = {China, COVID-19, epidemiology, OpenDataSet, vaccine},
pubstate = {published},
tppubtype = {article}
}
The coronavirus disease 2019 (COVID-19) pandemic has posed substantial challenges to the formulation of preventive interventions, particularly since the effects of physical distancing measures and upcoming vaccines on reducing susceptible social contacts and eventually halting transmission remain unclear. Here, using anonymized mobile geolocation data in China, we devise a mobility-associated social contact index to quantify the impact of both physical distancing and vaccination measures in a unified way. Building on this index, our epidemiological model reveals that vaccination combined with physical distancing can contain resurgences without relying on stay-at-home restrictions, whereas a gradual vaccination process alone cannot achieve this. Further, for cities with medium population density, vaccination can reduce the duration of physical distancing by 36% to 78%, whereas for cities with high population density, infection numbers can be well-controlled through moderate physical distancing. These findings improve our understanding of the joint effects of vaccination and physical distancing with respect to a city’s population density and social contact patterns.
14.
Plessis, Louis; McCrone, John T.; Zarebski, Alexander E.; Hill, Verity; Ruis, Christopher; Gutierrez, Bernardo; Raghwani, Jayna; Ashworth, Jordan; Colquhoun, Rachel; Connor, Thomas R.; Faria, Nuno R.; Jackson, Ben; Loman, Nicholas J.; O’Toole, Ãine; Nicholls, Samuel M.; Parag, Kris V.; Scher, Emily; Vasylyeva, Tetyana I.; Volz, Erik M.; Watts, Alexander; Bogoch, Isaac I.; Khan, Kamran; null,; Aanensen, David M.; Kraemer, Moritz U. G.; Rambaut, Andrew; Pybus, Oliver G.
Establishment and lineage dynamics of the SARS-CoV-2 epidemic in the UK Journal Article
In: Science, vol. 371, no. 6530, pp. 708-712, 2021.
Abstract | Links | BibTeX | Tags: COVID-19, epidemiology, genome, OpenDataSet, phylogenetic, travel, United Kingdom
@article{doi:10.1126/science.abf2946,
title = {Establishment and lineage dynamics of the SARS-CoV-2 epidemic in the UK},
author = {Louis Plessis and John T. McCrone and Alexander E. Zarebski and Verity Hill and Christopher Ruis and Bernardo Gutierrez and Jayna Raghwani and Jordan Ashworth and Rachel Colquhoun and Thomas R. Connor and Nuno R. Faria and Ben Jackson and Nicholas J. Loman and Ãine O’Toole and Samuel M. Nicholls and Kris V. Parag and Emily Scher and Tetyana I. Vasylyeva and Erik M. Volz and Alexander Watts and Isaac I. Bogoch and Kamran Khan and null and David M. Aanensen and Moritz U. G. Kraemer and Andrew Rambaut and Oliver G. Pybus},
doi = {10.1126/science.abf2946 URL = https://www.science.org/doi/abs/10.1126/science.abf2946},
year = {2021},
date = {2021-01-01},
urldate = {2021-01-01},
journal = {Science},
volume = {371},
number = {6530},
pages = {708-712},
abstract = {The scale of genome-sequencing efforts for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is unprecedented. The United Kingdom has contributed more than 26,000 sequences to this effort. This volume of data allowed du Plessis et al. to develop a detailed picture of the influxes of virus reaching U.K. shores as the pandemic developed during the first months of 2020 (see the Perspective by Nelson). Before lockdown, high travel volumes and few restrictions on international travel allowed more than 1000 lineages to become established. This accelerated local epidemic growth and exceeded contact tracing capacity. The authors were able to quantify the abundance, size distribution, and spatial range of the lineages that were transmitted. Transmission was highly heterogeneous, favoring some lineages that became widespread and subsequently harder to eliminate. This dire history indicates that rapid or even preemptive responses should have been used as they were elsewhere where containment was successful. Science, this issue p. 708; see also p. 680 Large-scale virus genome sequencing reveals the genetic structure and importation dynamics of a national COVID-19 epidemic. The United Kingdom's COVID-19 epidemic during early 2020 was one of world's largest and was unusually well represented by virus genomic sampling. We determined the fine-scale genetic lineage structure of this epidemic through analysis of 50,887 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genomes, including 26,181 from the UK sampled throughout the country's first wave of infection. Using large-scale phylogenetic analyses combined with epidemiological and travel data, we quantified the size, spatiotemporal origins, and persistence of genetically distinct UK transmission lineages. Rapid fluctuations in virus importation rates resulted in 1000 lineages; those introduced prior to national lockdown tended to be larger and more dispersed. Lineage importation and regional lineage diversity declined after lockdown, whereas lineage elimination was size-dependent. We discuss the implications of our genetic perspective on transmission dynamics for COVID-19 epidemiology and control.},
keywords = {COVID-19, epidemiology, genome, OpenDataSet, phylogenetic, travel, United Kingdom},
pubstate = {published},
tppubtype = {article}
}
The scale of genome-sequencing efforts for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is unprecedented. The United Kingdom has contributed more than 26,000 sequences to this effort. This volume of data allowed du Plessis et al. to develop a detailed picture of the influxes of virus reaching U.K. shores as the pandemic developed during the first months of 2020 (see the Perspective by Nelson). Before lockdown, high travel volumes and few restrictions on international travel allowed more than 1000 lineages to become established. This accelerated local epidemic growth and exceeded contact tracing capacity. The authors were able to quantify the abundance, size distribution, and spatial range of the lineages that were transmitted. Transmission was highly heterogeneous, favoring some lineages that became widespread and subsequently harder to eliminate. This dire history indicates that rapid or even preemptive responses should have been used as they were elsewhere where containment was successful. Science, this issue p. 708; see also p. 680 Large-scale virus genome sequencing reveals the genetic structure and importation dynamics of a national COVID-19 epidemic. The United Kingdom's COVID-19 epidemic during early 2020 was one of world's largest and was unusually well represented by virus genomic sampling. We determined the fine-scale genetic lineage structure of this epidemic through analysis of 50,887 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genomes, including 26,181 from the UK sampled throughout the country's first wave of infection. Using large-scale phylogenetic analyses combined with epidemiological and travel data, we quantified the size, spatiotemporal origins, and persistence of genetically distinct UK transmission lineages. Rapid fluctuations in virus importation rates resulted in 1000 lineages; those introduced prior to national lockdown tended to be larger and more dispersed. Lineage importation and regional lineage diversity declined after lockdown, whereas lineage elimination was size-dependent. We discuss the implications of our genetic perspective on transmission dynamics for COVID-19 epidemiology and control.
13.
Ingelbeen, Brecht; Peckeu, Laur`ene; Laga, Marie; Hendrix, Ilona; Neven, Inge; Sande, Marianne AB; Kleef, Esther
Reducing contacts to stop SARS-CoV-2 transmission during the second pandemic wave in Brussels, Belgium, August to November 2020 Journal Article
In: Eurosurveillance, vol. 26, no. 7, pp. 2100065, 2021.
Abstract | Links | BibTeX | Tags: Belgium, COVID-19, epidemiology, Model, school, transmission
@article{ingelbeen2021reducing,
title = {Reducing contacts to stop SARS-CoV-2 transmission during the second pandemic wave in Brussels, Belgium, August to November 2020},
author = {Brecht Ingelbeen and Laur`ene Peckeu and Marie Laga and Ilona Hendrix and Inge Neven and Marianne AB Sande and Esther Kleef},
doi = {https://doi.org/10.1371/journal.pbio.3001115},
year = {2021},
date = {2021-01-01},
urldate = {2021-01-01},
journal = {Eurosurveillance},
volume = {26},
number = {7},
pages = {2100065},
publisher = {European Centre for Disease Prevention and Control},
abstract = {To evaluate the effect of physical distancing and school reopening in Brussels between August and November 2020, we monitored changes in the number of reported contacts per SARS-CoV-2 case and associated SARS-CoV-2 transmission. The second COVID-19 pandemic wave in Brussels was the result of increased social contact across all ages following school reopening. Physical distancing measures including closure of bars and restaurants, and limiting close contacts, while primary and secondary schools remained open, reduced social mixing and controlled SARS-CoV-2 transmission.},
keywords = {Belgium, COVID-19, epidemiology, Model, school, transmission},
pubstate = {published},
tppubtype = {article}
}
To evaluate the effect of physical distancing and school reopening in Brussels between August and November 2020, we monitored changes in the number of reported contacts per SARS-CoV-2 case and associated SARS-CoV-2 transmission. The second COVID-19 pandemic wave in Brussels was the result of increased social contact across all ages following school reopening. Physical distancing measures including closure of bars and restaurants, and limiting close contacts, while primary and secondary schools remained open, reduced social mixing and controlled SARS-CoV-2 transmission.
12.
Oidtman, Rachel J; Omodei, Elisa; Kraemer, Moritz UG; Casteneda-Orjuela, Carlos A; Cruz-Rivera, Erica; Misnaza-Castrillon, Sandra; Cifuentes, Myriam Patricia; Rincon, Luz Emilse; Canon, Viviana; Alarcon, Pedro; others,
Trade-offs between individual and ensemble forecasts of an emerging infectious disease Journal Article
In: Nature Communications, vol. 12, no. 5379 , 2021.
Abstract | Links | BibTeX | Tags: epidemiology, infectious diseases, Model, Zika
@article{oidtman2021trade,
title = {Trade-offs between individual and ensemble forecasts of an emerging infectious disease},
author = {Rachel J Oidtman and Elisa Omodei and Moritz UG Kraemer and Carlos A Casteneda-Orjuela and Erica Cruz-Rivera and Sandra Misnaza-Castrillon and Myriam Patricia Cifuentes and Luz Emilse Rincon and Viviana Canon and Pedro Alarcon and others},
url = {https://www.nature.com/articles/s41467-021-25695-0},
doi = {https://doi.org/10.1038/s41467-021-25695-0},
year = {2021},
date = {2021-01-01},
urldate = {2021-01-01},
journal = {Nature Communications},
volume = {12},
number = {5379 },
publisher = {Cold Spring Harbor Laboratory Press},
abstract = {Probabilistic forecasts play an indispensable role in answering questions about the spread of newly emerged pathogens. However, uncertainties about the epidemiology of emerging pathogens can make it difficult to choose among alternative model structures and assumptions. To assess the potential for uncertainties about emerging pathogens to affect forecasts of their spread, we evaluated the performance 16 forecasting models in the context of the 2015-2016 Zika epidemic in Colombia. Each model featured a different combination of assumptions about human mobility, spatiotemporal variation in transmission potential, and the number of virus introductions. We found that which model assumptions had the most ensemble weight changed through time. We additionally identified a trade-off whereby some individual models outperformed ensemble models early in the epidemic, but on average the ensembles outperformed all individual models. Our results suggest that multiple models spanning uncertainty across alternative assumptions are necessary to obtain robust forecasts for emerging infectious diseases.},
keywords = {epidemiology, infectious diseases, Model, Zika},
pubstate = {published},
tppubtype = {article}
}
Probabilistic forecasts play an indispensable role in answering questions about the spread of newly emerged pathogens. However, uncertainties about the epidemiology of emerging pathogens can make it difficult to choose among alternative model structures and assumptions. To assess the potential for uncertainties about emerging pathogens to affect forecasts of their spread, we evaluated the performance 16 forecasting models in the context of the 2015-2016 Zika epidemic in Colombia. Each model featured a different combination of assumptions about human mobility, spatiotemporal variation in transmission potential, and the number of virus introductions. We found that which model assumptions had the most ensemble weight changed through time. We additionally identified a trade-off whereby some individual models outperformed ensemble models early in the epidemic, but on average the ensembles outperformed all individual models. Our results suggest that multiple models spanning uncertainty across alternative assumptions are necessary to obtain robust forecasts for emerging infectious diseases.
11.
Pullano, Giulia; Domenico, Laura Di; Sabbatini, Chiara E; Valdano, Eugenio; Turbelin, Clément; Debin, Marion; Guerrisi, Caroline; Kengne-Kuetche, Charly; Souty, Cécile; Hanslik, Thomas; others,
Underdetection of cases of COVID-19 in France threatens epidemic control Journal Article
In: Nature, vol. 590, no. 7844, pp. 134–139, 2021.
Abstract | Links | BibTeX | Tags: COVID-19, epidemiology, France, OpenDataSet, surveillance
@article{pullano2021underdetection,
title = {Underdetection of cases of COVID-19 in France threatens epidemic control},
author = {Giulia Pullano and Laura Di Domenico and Chiara E Sabbatini and Eugenio Valdano and Clément Turbelin and Marion Debin and Caroline Guerrisi and Charly Kengne-Kuetche and Cécile Souty and Thomas Hanslik and others},
doi = { https://doi.org/10.1038/s41586-020-03095-6},
year = {2021},
date = {2021-01-01},
urldate = {2021-01-01},
journal = {Nature},
volume = {590},
number = {7844},
pages = {134--139},
publisher = {Nature Publishing Group},
abstract = {As countries in Europe gradually relaxed lockdown restrictions after the first wave, test–trace–isolate strategies became critical to maintain the incidence of coronavirus disease 2019 (COVID-19) at low levels1,2. Reviewing their shortcomings can provide elements to consider in light of the second wave that is currently underway in Europe. Here we estimate the rate of detection of symptomatic cases of COVID-19 in France after lockdown through the use of virological3 and participatory syndromic4 surveillance data coupled with mathematical transmission models calibrated to regional hospitalizations2. Our findings indicate that around 90,000 symptomatic infections, corresponding to 9 out 10 cases, were not ascertained by the surveillance system in the first 7 weeks after lockdown from 11 May to 28 June 2020, although the test positivity rate did not exceed the 5% recommendation of the World Health Organization (WHO)5. The median detection rate increased from 7% (95% confidence interval, 6–8%) to 38% (35–44%) over time, with large regional variations, owing to a strengthening of the system as well as a decrease in epidemic activity. According to participatory surveillance data, only 31% of individuals with COVID-19-like symptoms consulted a doctor in the study period. This suggests that large numbers of symptomatic cases of COVID-19 did not seek medical advice despite recommendations, as confirmed by serological studies6,7. Encouraging awareness and same-day healthcare-seeking behaviour of suspected cases of COVID-19 is critical to improve detection. However, the capacity of the system remained insufficient even at the low epidemic activity achieved after lockdown, and was predicted to deteriorate rapidly with increasing incidence of COVID-19 cases. Substantially more aggressive, targeted and efficient testing with easier access is required to act as a tool to control the COVID-19 pandemic. The testing strategy will be critical to enable partial lifting of the current restrictive measures in Europe and to avoid a third wave.},
keywords = {COVID-19, epidemiology, France, OpenDataSet, surveillance},
pubstate = {published},
tppubtype = {article}
}
As countries in Europe gradually relaxed lockdown restrictions after the first wave, test–trace–isolate strategies became critical to maintain the incidence of coronavirus disease 2019 (COVID-19) at low levels1,2. Reviewing their shortcomings can provide elements to consider in light of the second wave that is currently underway in Europe. Here we estimate the rate of detection of symptomatic cases of COVID-19 in France after lockdown through the use of virological3 and participatory syndromic4 surveillance data coupled with mathematical transmission models calibrated to regional hospitalizations2. Our findings indicate that around 90,000 symptomatic infections, corresponding to 9 out 10 cases, were not ascertained by the surveillance system in the first 7 weeks after lockdown from 11 May to 28 June 2020, although the test positivity rate did not exceed the 5% recommendation of the World Health Organization (WHO)5. The median detection rate increased from 7% (95% confidence interval, 6–8%) to 38% (35–44%) over time, with large regional variations, owing to a strengthening of the system as well as a decrease in epidemic activity. According to participatory surveillance data, only 31% of individuals with COVID-19-like symptoms consulted a doctor in the study period. This suggests that large numbers of symptomatic cases of COVID-19 did not seek medical advice despite recommendations, as confirmed by serological studies6,7. Encouraging awareness and same-day healthcare-seeking behaviour of suspected cases of COVID-19 is critical to improve detection. However, the capacity of the system remained insufficient even at the low epidemic activity achieved after lockdown, and was predicted to deteriorate rapidly with increasing incidence of COVID-19 cases. Substantially more aggressive, targeted and efficient testing with easier access is required to act as a tool to control the COVID-19 pandemic. The testing strategy will be critical to enable partial lifting of the current restrictive measures in Europe and to avoid a third wave.
10.
Lemey, Philippe; Ruktanonchai, Nick; Hong, Samuel L; Colizza, Vittoria; Poletto, Chiara; den Broeck, Frederik Van; Gill, Mandev S; Ji, Xiang; Levasseur, Anthony; Munnink, Bas B Oude; others,
Untangling introductions and persistence in COVID-19 resurgence in Europe Journal Article
In: Nature, vol. 595, no. 7869, pp. 713–717, 2021.
Abstract | Links | BibTeX | Tags: big data, COVID-19, epidemiology, Europe, measures, mobility
@article{lemey2021untangling,
title = {Untangling introductions and persistence in COVID-19 resurgence in Europe},
author = {Philippe Lemey and Nick Ruktanonchai and Samuel L Hong and Vittoria Colizza and Chiara Poletto and Frederik Van den Broeck and Mandev S Gill and Xiang Ji and Anthony Levasseur and Bas B Oude Munnink and others},
doi = {https://doi.org/10.1038/s41586-021-03754-2},
year = {2021},
date = {2021-01-01},
urldate = {2021-01-01},
journal = {Nature},
volume = {595},
number = {7869},
pages = {713--717},
publisher = {Nature Publishing Group},
abstract = {After the first wave of SARS-CoV-2 infections in spring 2020, Europe experienced a resurgence of the virus starting in late summer 2020 that was deadlier and more difficult to contain1. Relaxed intervention measures and summer travel have been implicated as drivers of the second wave2. Here we build a phylogeographical model to evaluate how newly introduced lineages, as opposed to the rekindling of persistent lineages, contributed to the resurgence of COVID-19 in Europe. We inform this model using genomic, mobility and epidemiological data from 10 European countries and estimate that in many countries more than half of the lineages circulating in late summer resulted from new introductions since 15 June 2020. The success in onward transmission of newly introduced lineages was negatively associated with the local incidence of COVID-19 during this period. The pervasive spread of variants in summer 2020 highlights the threat of viral dissemination when restrictions are lifted, and this needs to be carefully considered in strategies to control the current spread of variants that are more transmissible and/or evade immunity. Our findings indicate that more effective and coordinated measures are required to contain the spread through cross-border travel even as vaccination is reducing disease burden.},
keywords = {big data, COVID-19, epidemiology, Europe, measures, mobility},
pubstate = {published},
tppubtype = {article}
}
After the first wave of SARS-CoV-2 infections in spring 2020, Europe experienced a resurgence of the virus starting in late summer 2020 that was deadlier and more difficult to contain1. Relaxed intervention measures and summer travel have been implicated as drivers of the second wave2. Here we build a phylogeographical model to evaluate how newly introduced lineages, as opposed to the rekindling of persistent lineages, contributed to the resurgence of COVID-19 in Europe. We inform this model using genomic, mobility and epidemiological data from 10 European countries and estimate that in many countries more than half of the lineages circulating in late summer resulted from new introductions since 15 June 2020. The success in onward transmission of newly introduced lineages was negatively associated with the local incidence of COVID-19 during this period. The pervasive spread of variants in summer 2020 highlights the threat of viral dissemination when restrictions are lifted, and this needs to be carefully considered in strategies to control the current spread of variants that are more transmissible and/or evade immunity. Our findings indicate that more effective and coordinated measures are required to contain the spread through cross-border travel even as vaccination is reducing disease burden.
9.
Trentini, Filippo; Marziano, Valentina; Guzzetta, Giorgio; Tirani, Marcello; Cereda, Danilo; Poletti, Piero; Piccarreta, Raffaella; Barone, Antonio; Preziosi, Giuseppe; Arduini, Fabio; Valle, Petra Giulia Della; Zanella, Alberto; Grosso, Francesca; Castillo, Gabriele; Castrofino, Ambra; Grasselli, Giacomo; Melegaro, Alessia; Piatti, Alessandra; Andreassi, Aida; Gramegna, Maria; Ajelli, Marco; Merler, Stefano
In: American Journal of Epidemiology, 2021, ISSN: 0002-9262, (kwab252).
Abstract | Links | BibTeX | Tags: big data, COVID-19, epidemiology, ICU, Italy, Public Health
@article{10.1093/aje/kwab252,
title = {The pressure on healthcare system and intensive care utilization during the COVID-19 outbreak in the Lombardy region: a retrospective observational study on 43,538 hospitalized patients},
author = {Filippo Trentini and Valentina Marziano and Giorgio Guzzetta and Marcello Tirani and Danilo Cereda and Piero Poletti and Raffaella Piccarreta and Antonio Barone and Giuseppe Preziosi and Fabio Arduini and Petra Giulia Della Valle and Alberto Zanella and Francesca Grosso and Gabriele Castillo and Ambra Castrofino and Giacomo Grasselli and Alessia Melegaro and Alessandra Piatti and Aida Andreassi and Maria Gramegna and Marco Ajelli and Stefano Merler},
url = {https://doi.org/10.1093/aje/kwab252},
doi = {10.1093/aje/kwab252},
issn = {0002-9262},
year = {2021},
date = {2021-01-01},
urldate = {2021-01-01},
journal = {American Journal of Epidemiology},
abstract = {During the spring of 2020, the COVID-19 epidemic caused an unprecedented demand for intensive care resources in Lombardy, Italy. Using data on 43,538 hospitalized patients admitted between February 21 and July 12, 2020, we evaluated variations in intensive care unit (ICU) admissions and mortality over three periods: the early phase (February 20-March 13), the period of highest pressure on healthcare (March 14-April 25, when COVID-19 patients exceeded the ICU pre-pandemic bed capacity), and the declining phase (April 26-July 12).Compared to the early phase, patients above 70 years of age were admitted less often to an ICU during highest pressure on healthcare (odds ratio OR 0.47, 95%CI: 0.41-0.54) with longer delays (incidence rate ratio IRR 1.82, 95%CI: 1.52-2.18), and lower chances of death in ICU (OR 0.47, 95%CI: 0.34-0.64). Patients under 56 years of age reported more limited changes in the probability (OR 0.65, 95%CI: 0.56-0.76) and delay to ICU admission (IRR 1.16, 95%CI: 0.95-1.42) and an increased mortality (OR 1.43, 95%CI: 1.00-2.07). In the declining phase, all quantities decreased for all age groups.These patterns may suggest that limited healthcare resources during the peak epidemic phase in Lombardy forced a shift in ICU admission criteria to prioritize patients with higher chances of survival.},
note = {kwab252},
keywords = {big data, COVID-19, epidemiology, ICU, Italy, Public Health},
pubstate = {published},
tppubtype = {article}
}
During the spring of 2020, the COVID-19 epidemic caused an unprecedented demand for intensive care resources in Lombardy, Italy. Using data on 43,538 hospitalized patients admitted between February 21 and July 12, 2020, we evaluated variations in intensive care unit (ICU) admissions and mortality over three periods: the early phase (February 20-March 13), the period of highest pressure on healthcare (March 14-April 25, when COVID-19 patients exceeded the ICU pre-pandemic bed capacity), and the declining phase (April 26-July 12).Compared to the early phase, patients above 70 years of age were admitted less often to an ICU during highest pressure on healthcare (odds ratio OR 0.47, 95%CI: 0.41-0.54) with longer delays (incidence rate ratio IRR 1.82, 95%CI: 1.52-2.18), and lower chances of death in ICU (OR 0.47, 95%CI: 0.34-0.64). Patients under 56 years of age reported more limited changes in the probability (OR 0.65, 95%CI: 0.56-0.76) and delay to ICU admission (IRR 1.16, 95%CI: 0.95-1.42) and an increased mortality (OR 1.43, 95%CI: 1.00-2.07). In the declining phase, all quantities decreased for all age groups.These patterns may suggest that limited healthcare resources during the peak epidemic phase in Lombardy forced a shift in ICU admission criteria to prioritize patients with higher chances of survival.
8.
Rader, Benjamin; Scarpino, Samuel V; Nande, Anjalika; Hill, Alison L; Adlam, Ben; Reiner, Robert C; Pigott, David M; Gutierrez, Bernardo; Zarebski, Alexander E; Shrestha, Munik; others,
Crowding and the shape of COVID-19 epidemics Journal Article
In: Nature medicine, vol. 26, no. 12, pp. 1829–1834, 2020.
Abstract | Links | BibTeX | Tags: COVID-19, epidemiology, OpenDataSet, population dynamics
@article{rader2020crowding,
title = {Crowding and the shape of COVID-19 epidemics},
author = {Benjamin Rader and Samuel V Scarpino and Anjalika Nande and Alison L Hill and Ben Adlam and Robert C Reiner and David M Pigott and Bernardo Gutierrez and Alexander E Zarebski and Munik Shrestha and others},
doi = {https://doi.org/10.1038/s41591-020-1104-0},
year = {2020},
date = {2020-01-01},
urldate = {2020-01-01},
journal = {Nature medicine},
volume = {26},
number = {12},
pages = {1829--1834},
publisher = {Nature Publishing Group},
abstract = {The coronavirus disease 2019 (COVID-19) pandemic is straining public health systems worldwide, and major non-pharmaceutical interventions have been implemented to slow its spread. During the initial phase of the outbreak, dissemination of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was primarily determined by human mobility from Wuhan, China. Yet empirical evidence on the effect of key geographic factors on local epidemic transmission is lacking. In this study, we analyzed highly resolved spatial variables in cities, together with case count data, to investigate the role of climate, urbanization and variation in interventions. We show that the degree to which cases of COVID-19 are compressed into a short period of time (peakedness of the epidemic) is strongly shaped by population aggregation and heterogeneity, such that epidemics in crowded cities are more spread over time, and crowded cities have larger total attack rates than less populated cities. Observed differences in the peakedness of epidemics are consistent with a meta-population model of COVID-19 that explicitly accounts for spatial hierarchies. We paired our estimates with globally comprehensive data on human mobility and predict that crowded cities worldwide could experience more prolonged epidemics.},
keywords = {COVID-19, epidemiology, OpenDataSet, population dynamics},
pubstate = {published},
tppubtype = {article}
}
The coronavirus disease 2019 (COVID-19) pandemic is straining public health systems worldwide, and major non-pharmaceutical interventions have been implemented to slow its spread. During the initial phase of the outbreak, dissemination of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was primarily determined by human mobility from Wuhan, China. Yet empirical evidence on the effect of key geographic factors on local epidemic transmission is lacking. In this study, we analyzed highly resolved spatial variables in cities, together with case count data, to investigate the role of climate, urbanization and variation in interventions. We show that the degree to which cases of COVID-19 are compressed into a short period of time (peakedness of the epidemic) is strongly shaped by population aggregation and heterogeneity, such that epidemics in crowded cities are more spread over time, and crowded cities have larger total attack rates than less populated cities. Observed differences in the peakedness of epidemics are consistent with a meta-population model of COVID-19 that explicitly accounts for spatial hierarchies. We paired our estimates with globally comprehensive data on human mobility and predict that crowded cities worldwide could experience more prolonged epidemics.
7.
Lai, Shengjie; Ruktanonchai, Nick W; Zhou, Liangcai; Prosper, Olivia; Luo, Wei; Floyd, Jessica R; Wesolowski, Amy; Santillana, Mauricio; Zhang, Chi; Du, Xiangjun; others,
Effect of non-pharmaceutical interventions to contain COVID-19 in China Journal Article
In: nature, vol. 585, no. 7825, pp. 410–413, 2020.
Abstract | Links | BibTeX | Tags: COVID-19, epidemiology, health policy, Model
@article{lai2020effect,
title = {Effect of non-pharmaceutical interventions to contain COVID-19 in China},
author = {Shengjie Lai and Nick W Ruktanonchai and Liangcai Zhou and Olivia Prosper and Wei Luo and Jessica R Floyd and Amy Wesolowski and Mauricio Santillana and Chi Zhang and Xiangjun Du and others},
doi = {https://doi.org/10.1038/s41586-020-2293-x},
year = {2020},
date = {2020-01-01},
urldate = {2020-01-01},
journal = {nature},
volume = {585},
number = {7825},
pages = {410--413},
publisher = {Nature Publishing Group},
abstract = {On 11 March 2020, the World Health Organization (WHO) declared coronavirus disease 2019 (COVID-19) a pandemic1. The strategies based on non-pharmaceutical interventions that were used to contain the outbreak in China appear to be effective2, but quantitative research is still needed to assess the efficacy of non-pharmaceutical interventions and their timings3. Here, using epidemiological data on COVID-19 and anonymized data on human movement, we develop a modelling framework that uses daily travel networks to simulate different outbreak and intervention scenarios across China. We estimate that there were a total of 114,325 cases of COVID-19 (interquartile range 76,776–164,576) in mainland China as of 29 February 2020. Without non-pharmaceutical interventions, we predict that the number of cases would have been 67-fold higher (interquartile range 44–94-fold) by 29 February 2020, and we find that the effectiveness of different interventions varied. We estimate that early detection and isolation of cases prevented more infections than did travel restrictions and contact reductions, but that a combination of non-pharmaceutical interventions achieved the strongest and most rapid effect. According to our model, the lifting of travel restrictions from 17 February 2020 does not lead to an increase in cases across China if social distancing interventions can be maintained, even at a limited level of an on average 25% reduction in contact between individuals that continues until late April. These findings improve our understanding of the effects of non-pharmaceutical interventions on COVID-19, and will inform response efforts across the world.},
keywords = {COVID-19, epidemiology, health policy, Model},
pubstate = {published},
tppubtype = {article}
}
On 11 March 2020, the World Health Organization (WHO) declared coronavirus disease 2019 (COVID-19) a pandemic1. The strategies based on non-pharmaceutical interventions that were used to contain the outbreak in China appear to be effective2, but quantitative research is still needed to assess the efficacy of non-pharmaceutical interventions and their timings3. Here, using epidemiological data on COVID-19 and anonymized data on human movement, we develop a modelling framework that uses daily travel networks to simulate different outbreak and intervention scenarios across China. We estimate that there were a total of 114,325 cases of COVID-19 (interquartile range 76,776–164,576) in mainland China as of 29 February 2020. Without non-pharmaceutical interventions, we predict that the number of cases would have been 67-fold higher (interquartile range 44–94-fold) by 29 February 2020, and we find that the effectiveness of different interventions varied. We estimate that early detection and isolation of cases prevented more infections than did travel restrictions and contact reductions, but that a combination of non-pharmaceutical interventions achieved the strongest and most rapid effect. According to our model, the lifting of travel restrictions from 17 February 2020 does not lead to an increase in cases across China if social distancing interventions can be maintained, even at a limited level of an on average 25% reduction in contact between individuals that continues until late April. These findings improve our understanding of the effects of non-pharmaceutical interventions on COVID-19, and will inform response efforts across the world.