Research finds Covid in France before Wuhan market outbreak

A French study has found that the SARS-CoV-2 virus could have been circulating in France up to a month earlier than the first reported cases from Wuhan, China.

National health research body Inserm said: “The first identified cases of COVID-19 were detected on December 8, 2019, in Wuhan, China; and the first documented case in Europe was reported retrospectively in France… on December 27".

But, it added, new research “suggests early circulation of SARS-CoV-2 in Europe” going back to at least November 2019 in France, and even earlier in Italy.

Blood samples reveal November infections

In the study, scientists analysed 9,144 blood samples taken from a pool of 200,000 male and female adult participants, living in all regions of mainland France. The samples had been collected between November 4, 2019, and March 16, 2020.

They were first analysed using a rapid Elisa test to detect Covid-19 antibodies and the virus was found in 353 participants.

To discount false positives, a second highly specific test was then done on these samples. This showed 13 of the samples taken between November 5, 2019 and January 30, 2020 came back “SN positive” meaning the Covid-19 virus had been detected.

Seven of these samples were taken in November 2019.

Evidence of early circulation of SARS-CoV-2 in France: findings from the population-based “CONSTANCES” cohort (Inserm/Springer Link)

Positive cases from travel and contact with sick

Interviews were conducted with 11 of the 13 participants to investigate their symptoms and possible causes of infection.

Inserm said: “Five participants experienced signs of viral respiratory illnesses and eight had close contact with persons who exhibited such signs, or reported situations at risk, of potential SARS-CoV-2 exposure.”

Professor Fabrice Carrat, director of the study, told Le Monde: “In over half of the cases, we are dealing with people who had travelled and had been in contact with people who had been sick.”

One of the participants was also a doctor, which increased their risk of exposure, he said. Another - who tested positive in November - said her partner had been ill with a severe cough in October 2019.

The professor said: “These results suggest that as early as November and December, the rate of contamination among people in France was already around one case per 1,000 people. We seem to have found cases sporadically, all over the country.”

The results of the study, published on February 6, also give evidence of the virus spreading in Italy as early as autumn 2019.

French results correspond with WHO findings

The results of the study appear to confirm the findings of experts from the World Health Organisation, which has been investigating the origins of the virus in Wuhan.

This week, the experts told the press there was “no indication” that the virus was circulating in Wuhan prior to the first official cases being recorded there in December 2019. They said it was possible the virus was circulating in other regions in China before it was detected in Wuhan.

Researchers debunked the controversial theory that the virus was started in a lab by scientists as “extremely unlikely”. They are still investigating whether it may have been spread to humans from animals, such as bats or pangolins, a scaly mammal eaten as a delicacy in China, or through imported frozen foods.

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