The Covid-19 was present in France from the fall of 2019. This is what French researchers from theNational Institute of Health and Medical Research (Inserm), whose work, published on February 6 in the journal European Journal of Epidemiology, are relayed and detailed in The world (paid item) and on the Inserm website on Wednesday 10 February.
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How did these scientists do it? They first analyzed 9,144 blood samples collected from the 200,000 participants of the Constances cohort, a large epidemiological study on the coronavirus, collected between November 4, 2019 and March 16, 2020. “They first screened them with a rapid test detecting anti-Sars-CoV-2 immunoglobulins type G (IgG)”, details The world. The virus was then detected among 353 participants, says Inserm. To avoid ending up with “false positives”, the researchers then performed a second test “very specific”. Thus, thirteen samples taken between November 5, 2019 and January 30, 2020 were found to be positive on both tests.
Eleven positive cases were the subject of further investigation, six of which did not report any symptoms in the weeks preceding the sample collection, continues Inserm. “Five participants, however, exhibited signs of viral respiratory disease, and eight had close contact with people who exhibited such signs or reported risk situations for potential exposure to Sars-CoV-2”, specifies the Institute in its article on this study.
“In more than half of the cases, we are dealing with people who have traveled or who have been in contact with people who have been ill. One of the cases had traveled for two months in Asia and returned to France in early December … Another is a doctor, which is also a risk factor “, explains Professor Fabrice Carrat, director of the study, in The world. Another example: a woman in her thirties, positive in November, explained that her partner suffered from a severe cough in October.
“These results suggest that from the months of November and December, the rate of contamination in the French population is already of the order of one case per thousand. We seem to find cases sporadically, all over the territory. “Fabrice Carrat
in the world”
So far, the first French case of Covid-19 confirmed by PCR test is Amirouche Hammar. This inhabitant of Bobigny (Seine-Saint-Denis) went to the emergency room of the Jean-Verdier hospital, in Bondy, on December 27, 2019. He was suffering from a pulmonary infection with severe “chest pain”. He had only learned at the end of April 2020 to be infected with Covid-19, thanks to a retrospective work carried out in the Jean-Verdier hospitals, in Bondy, and Avicenne, in Bobigny.
“These indications of an already sustained circulation of the new coronavirus in Europe as early as November, or even October, challenge the hypothesis of the start of the epidemic on the Huanan market, in Wuhan, China , at the beginning of December 2019 “, valued The world. A thesis that goes in the direction of the team’s words international experts from China and the World Health Organization, who investigated in Wuhan. On Tuesday, they announced that they had not found any indication of the presence of the coronavirus in this city before its appearance in December 2019.