CoMix: comparing mixing patterns in the Belgian population during and after lockdown

• Published in: Scientific reports Vol. 10; no. 1; p. 21885
• Main Authors: Coletti, Pietro, Wambua, James, Gimma, Amy, Willem, Lander, Vercruysse, Sarah, Vanhoutte, Bieke, Jarvis, Christopher I, Van Zandvoort, Kevin, Edmunds, John, Beutels, Philippe, Hens, Niel
• Format: Journal Article
• Language: English
• Published: England Nature Publishing Group 14.12.2020; Nature Publishing Group UK; Nature Portfolio
• Subjects: Adolescent; Adult; Age; Aged; Belgium - epidemiology; Coronaviruses; COVID-19; COVID-19 - transmission; Female; Hand Hygiene - statistics & numerical data; Humans; Hygiene; Longitudinal Studies; Male; Masks - statistics & numerical data; Middle Aged; Pandemics; Pandemics - prevention & control; Physical Distancing; Public health; Social distancing; Surveys and Questionnaires; Young Adult; Belgium
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-020-78540-7

The COVID-19 pandemic has shown how a newly emergent communicable disease can lay considerable burden on public health. To avoid system collapse, governments have resorted to several social distancing measures. In Belgium, this included a lockdown and a following period of phased re-opening. A representative sample of Belgian adults was asked about their contact behaviour from mid-April to the beginning of August, during different stages of the intervention measures in Belgium. Use of personal protection equipment (face masks) and compliance to hygienic measures was also reported. We estimated the expected reproduction number computing the ratio of [Formula: see text] with respect to pre-pandemic data. During the first two waves (the first month) of the survey, the reduction in the average number of contacts was around 80% and was quite consistent across all age-classes. The average number of contacts increased over time, particularly for the younger age classes, still remaining significantly lower than pre-pandemic values. From the end of May to the end of July , the estimated reproduction number has a median value larger than one, although with a wide dispersion. Estimated [Formula: see text] fell below one again at the beginning of August. We have shown how a rapidly deployed survey can measure compliance to social distancing and assess its impact on COVID-19 spread. Monitoring the effectiveness of social distancing recommendations is of paramount importance to avoid further waves of COVID-19.