Before revision: Based on a simple analysis of the reports of Sant\'e Public France , we show that the real incidence during the second wave of the Covid-19 outbreak is around 60\% of the mean positivity of virological tests realized week after week in France.
After revision: Large scale virological testing of SARS-Cov2 is implemented since May 2020 in France. We assume that the positivity of asymptomatic people not being contact cases (ANBC) is representative of the positivity of the whole French population, which allows estimating the real incidence. We estimate, using Sant\'e Public France , we show that the real incidence during the second wave of the Covid-19 outbreak is around 60\% of the mean positivity of virological tests realized week after week in France.