Researchers looking at data collected by Constances, a long-term study of the health of over 200,000 people in France, have uncovered a trove of information about French health and habits, including evidence that the Covid-19 virus was circulating in France well before the first official recorded case, reports Radio France Internationale (RFI).
As the Covid pandemic spread in France, Constances was an obvious place to turn to for information on the evolution of the disease.
“We collect blood and urine samples from the volunteers and we store them in liquid nitrogen for later use…and when Covid came, we took 9,000 samples and we analysed them looking for Covid serology," says Marcel Goldberg, an epidemiologist with Inserm, France’s health and medical research institute, and co-founder of Constances.
"It happens that we found some positive cases long before the first official case in France.”
France registered its first Covid patient on January 24th 2020, and then retrospectively diagnosed a case on December 27th 2019. Doctors had reported indications of Covid earlier through scans. The Constances blood samples allowed researchers to confirm the clinical observations.
They found Covid antibodies in 13 samples taken between November 4th 2019 and January 30th, suggesting the virus could have been circulating in France even before the first identified case in Wuhan, China, on December 8th 2019.
Since 2013, Constances has been recruiting tens of thousands of volunteers to undergo regular physical examinations and answer yearly questionnaires about their health and habits. Since the end of 2018, volunteers have been asked to provide blood and urine samples to be stored in a biobank for future research, like the search for Covid antibodies.
The goal is to gather as much data as possible about people’s health in France, to understand the effects of everything from diet, to the environment, to work conditions.
“We designed Constances not as a research project but as a research platform,” explains Goldberg. “It's like an observatory. It's a big scientific instrument, which is not designed to answer one specific question, but open to different research areas.”
Read more of this report from RFI.
Listen to an interview with Constances programme co-founder Marcel Goldberg on RFI's Spotlight on France podcast.