Photo Credit: Giuseppe
The following is a summary of “Evolution of social contacts patterns in France over the SARS-CoV-2 pandemic: results from the SocialCov survey,” published in the February 2025 issue of BMC Infectious Diseases by Soussand et al.
During 2020-2022, France enforced non-pharmaceutical interventions like lockdowns and curfews to lessen SARS-CoV-2 transmission and COVID-19 burden, alongside pandemic-driven individual behaviour changes.
Researchers conducted a retrospective study to present the results of the SocialCov survey, which indicated the evolution of contacts in France from December 2020 to May 2022, aiming to understand the short- and long-term impact of interventions on social mixing.
They distributed a questionnaire via 6 separate communication campaigns through the government’s TousAntiCovid app from December 2020 to June 2022. Participants provided details on their social contacts from the previous day, including the contact’s age, location, duration, and type (physical/conversational).
The results showed that 44,396 individuals participated in the survey across 6 campaigns, reporting a total of 3,007,35 contacts. Contact patterns changed over time as national mitigation measures eased. The average number of daily contacts increased from 5.3 in December 2020 to 9.7 in May 2022. Contact patterns varied by participant age, holidays, and weekends. Healthcare workers reported an average of 18.4 contacts per day during workdays, nearly double that of other workers and the risk perception fluctuated throughout the 2 years.
Investigators concluded the contact density in France evolved between 2020 and 2022, showing strong heterogeneities by age, employment status, and weekend/vacation periods, and that the derived contact matrices could inform age-stratified transmission models for respiratory pathogens during non-pharmaceutical interventions.
Source: bmcinfectdis.biomedcentral.com/articles/10.1186/s12879-025-10611-4
