The Institut Pasteur released a study this Thursday April 23, on medical preprints release website MedRxiv saying that the rate of people showing antibodies against coronavirus is currently not enough.
For this study, the Institut Pasteur led epidemiologic works, between March 30 and this April 3 in a high school in Crépy-en-Valois, one of the first coronavirus epidemic sources in France where a teacher died of the virus this past February 28.
According to the sero-epidemiologic study carried out with tests detecting antibodies, only 25.9% of teachers, students and families have been infected and developed antibodies against coronavirus, a proportion way too weak to say the immunity threshold is enough to consider herd immunity in France, while confinement said to start from May 11 in France is just around the corner.
The Institut Pasteur continues and says 41% of high-schoolers, teachers and staff have been infected by coronavirus in February and March, but only 11% of family members have developed antibodies. Far from the 70% expected to hope for herd immunity to be able to stop the virus propagation.
And these antibodies have to be effective against coronavirus and immunity to last in time, this is what Institut Pasteur’s first study writer and head of the epidemiologic unit of emerging diseases at the institute Arnaud Fontanet says. He adds “We have no certitude as for the protective character of antibodies”.
While underlying the positive effect of confinement that curbed the virus propagation, writers of the study of the Institut Pasteur suggest herd immunity will take time to settle on a long-term basis in France and hasty deconfinement is not the right solution.