What is the share of the French population already infected with Covid-19? This is what Institut Pasteur wondered and answers in a study released this Wednesday February 24, 2021. According to their results, about 17% of the mainland adult population over the age of 20 has been infected with Covid-19.
How useful are these estimations? First, experiments of the research-specialized medical center enable to “weigh up the share of the population likely to have developed immunity (at least partial and over the short term) against Sars-CoV-2 following natural infection”, the foundation explains.
How did they manage to get such results? To determine the infection share in different age ranges, Institut Pasteur has studied data including hospitalized patients, per region and age range. They also based their results on the “estimation of probability to get hospitalized when one is infected”.
30% of the population hit in Île-de-France
Therefore, searchers from the Institute have noticed major differences remain between the different age ranges, and depending on mainland regions. In people aged 70+, their study bets on more than 10% people contaminated already. In 20-29 years old, the same statistics is close to 15%. On the regional level, Île-de-France is the hardest hit area in the country, including 30% of the population infected since the Covid-19 epidemic broke out. Yet, western parts of the country, on the Atlantic coast, seems to have been rather spared by the spread of coronavirus.
But careful not to over-interpret these estimations: “be careful with the interpretation of these estimations” Institut Pasteur reminds on their website. The foundation underlines that “if infection undoubtedly confers immunity over the short term, it is possible for the latter to fade away with time”. Furthermore, the entire methodology used by the institute is based on “rather strong hypotheses”. For instance, “the hypothesis the likeliness to get hospitalized when infected has remained constant in each age range”, keep in mind that it is possible “that these probabilities change over the course of the pandemic or from one region to the other” scientists insist on.
