Towards a second wave?
Q: “Once the pandemic has passed in Quebec, the virus will not have disappeared. When normal activities resume, is it not logical to think that it will resume even though a small proportion of humans have developed antibodies? ”Asks Pascal Renauld.
A: This is a question that has taken a very concrete turn in the past week. Indeed, we read in a report from the Imperial College of London , “for the first time since the start of the outbreak, there have been no new confirmed cases in China which have been caused by local transmission. : the arrival of cases from abroad is something else], for five consecutive days as of March 23, 2020 “.
As China has lifted in recent weeks some of the severe quarantine measures it had implemented at the height of the epidemic, the document examines the effects of an at least partial resumption of movements inside from several Chinese cities as well as Hong Kong. His conclusion is that it seems possible to resume a certain level of economic activity (and therefore displacement) without relaunching the epidemic on dangerous exponential growth.
“These results do not rule out the possibility of future epidemics in China, nor do they indicate the maximum level of economic activity that will be resumed in the medium term. But they suggest that after a period of very intense social isolation that helped contain the spread, China has managed to break out of its strict social isolation policies with some degree of success, “concludes the text.
These are encouraging results, but there is still a big unknown in this whole story, commented microbial pathogenesis researcher Brendan Wren, of the London School of Hygiene and Tropical Medicine : “We still have no idea the proportion of the population that is immunologically naive [editor’s note: without antibodies to COVID-19] and still vulnerable to a potential re-outbreak of the virus. ”
So yes, a second wave remains possible. Depending on the number of people who will have been infected during the first, it will be a little or much less worse. But it must be said here that the purpose of the isolation measures in place is not really to avoid a second wave. It is rather to “smooth the curve”, as we say on social networks: spread the cases over time so that there are not, all of a sudden, more patients than the network of the health cannot take it. And from this point of view, it seems that isolation works well.
COVID-19 raises a lot of questions. In order to respond to as many people as possible, science journalists have decided to join forces. The media members of the National Cooperative of Independent Information ( Le Soleil, Le Droit, La Tribune, Le Nouvelliste, Le Quotidien and La Voix de l’Est ), Québec Science and the Déclic Center team up to answer your questions. . You have some? Write to us . This project is made possible thanks to a contribution from the Chief Scientist of Quebec , who invites you to follow him on Facebook , Twitter and Instagram .