Estimated date of dominance of VOC-202012/01 strain in France and projected scenarios01/2021Chiara E. Sabbatini, Laura Di Domenico, Giulia Pullano, Vittoria Colizza1, 2021.A new variant of SARS-CoV-2 (VOC-202012/01, here called VOC) emerged in late 2020 in the United Kingdom. Preliminary estimates indicate that 1.4% of newly diagnosed COVID-19 cases in w01 in the country are due to VOC. Using the model developed by INSERM to respond to the COVID-19 pandemic, we provide projections of the epidemic trajectories in the upcoming weeks due to increased VOC circulation in the country. We estimate that the variant would become dominant in France between late February and mid-March, depending on the epidemic evolution and estimated increase of VOC transmissibility. New weekly hospitalizations are expected to reach the level of the first wave’s peak (approximately 25,000 hospitalizations) between mid-February and early April, in absence of interventions. These results support the need for strengthened social distancing measures and for accelerating the vaccination campaign to face the threat of the VOC variant.
Mobility during the first two full weeks of the second lockdown in France11/2020Eugenio Valdano, Jonggul Lee, Stefania Rubrichi, Vittoria Colizza, 2020.France is on a second lockdown to stop the second wave of COVID-19. Closures and restrictions are impacting mobility at different spatial and temporal scales. This is an update of Report #22, published on November 12, 2020. We extend here the analysis by adding mobility data from the 2nd working week of the current LD. The following reported values do not include Nov 11 as it was a national holiday (Armistice du 1918), unless explicitly specified. We measured little change from the previous week in national average mobility (2nd week of current lockdown: 32% below pre-pandemic levels; 1st week: 33% below pre-pandemic levels), and markedly less reduction than the 1st LD (67% below pre-pandemic levels). Analyzing mobility by age class, by time of day, and by region showed roughly the same patterns as the previous week. We report a slight additional drop in mobility during morning rush hours (2nd week of current lockdown: 23% below pre-pandemic levels; 1st week: 20% below pre-pandemic levels), during which, however, mobility remained substantially higher than the 1st LD (23% v 73% below pre-pandemic levels). Measured mobility on Nov 11 (national holiday) was markedly lower than the rest of the week: 64% below pre-pandemic levels. Long-range mobility (trips longer than 100 km) on Nov 11 was instead higher than the rest of the week: 19% below pre-pandemic levels vs 26% below pre-pandemic levels on the rest of the week. Both represent a marked increase in mobility from the 1st week of the current LD (35% below pre-pandemic levels).
Expected impact of exit strategies after the second lockdown - France, Nov 202011/2020Giulia Pullano, Laura Di Domenico, Chiara E Sabbatini, Vittoria Colizza, 2020.This report is an update of previous reports on the expected impact of the second lockdown implemented in France on Friday, October 30 to suppress the second wave of COVID-19 epidemic. We provide updated projections simulating a mild lockdown with schools open informed on the estimates on mobility reduction recorded during the first week of lockdown from mobile phone data, and explore different exit strategies. The current report focuses on Île-de-France; analyses for other regions will follow.
Telework and other measures reducing the presence at work to slow down COVID-19pdm in France (Sept 2020).09/2020Giulia Pullano, Laura Di Domenico , Vittoria Colizza, 2020.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. 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.