Four months after the emergence of Covid-19, scientists still have a vague idea of the spread of the virus in the French population. Having a “picture” of the epidemic is, however, essential for making health decisions appropriate to the situation. It is this cliche as rare as it is instructive that the department of Morbihan has just taken. According to a serology study disclosed on Thursday May 28 (*), between 5 and 10% of its inhabitants have been in contact with the Sars-Cov-2 virus, responsible for Covid-19. A rate much higher than the models proposed by the Pasteur Institute, which estimated at 1.3% the proportion of people infected in Brittany. But still far from the levels deemed necessary to achieve group immunity and be protected against a second wave.
The study was coordinated by Open Health, a company specializing in the processing of health data. “Since our goal was to quickly assess the extent of the virus’s circulation,