As the virus is said to be under control in France, the fight against the coronavirus epidemic is not over yet. And even though Covid-19 seems to slow down in Europe, the hypothesis of a second wave is still considered by the scientific community.
In an interview with Le Figaro, Jerôme Salomon called French to be cautious: "Efforts shall be continued, even though if you are on holidays", adding the country shall "prepare for a resurgence of the epidemic and perhaps a second wave". Moreover, the arrival of cases imported may foretell a return of the epidemic this summer.
On June 22, 2020, the Scientific Committee said a second Covid-19 wave was “highly likely” this Fall. They recommend keep data collected since before the health crisis started. The French Medical Association (L’Ordre des Médecins) are not for extending the preservation of these data for confidentiality grounds.
What are evidences enabling us to think a second wave is likely? We give you answers:
Many epidemiologists notice some slackening
“Now we clearly see infections decrease, people think it is over. But it is not” European Center for Disease Prevention and Control (ECDC) head Andrea Ammon said back in May. The decreasing infection rate led many French people to stop being vigilant for several weeks, breaking social distancing or barrier gestures. A situation noticed recently for World Music Day, where many gatherings took place as they were banned, breaking the health requirements still implemented.
This relaxing, epidemiologists remind it in many medias. “The epidemic is under control, but the risk is still there. It is vital to keep social distancing and barrier gestures” Pascal Crépay, epidemiologist at the École des hautes études en Santé publique in Rennes, explains. A slackening that, if it continues, will spread the virus even more across the country and cause a second wave.
R0 is once again above 1 in many French regions
There are five of them, as of June 12, 2020, to have notice a resurgence of the epidemic, Santé Publique France explains: Auvergne-Rhône-Alpes, Occitanie, Martinique, Normandy, and French Guiana.
“In Normandy, the virus effective reproduction rate increased over the last week, up to exceeding the alert threshold set at 1.5” the Direction Générale de la santé explains. They add: “the number is now at 1.6”.
An increase that we can explain with two main factors, as our peers at Ouest France say: the increase of clusters, as well as the increase of the number of people tested, enabling to be more precise on the evolution of the virus and its propagation. What suggests a likely second wave is the growing R0 in some regions, increasing the domestic R0: still according to Ouest France, from June 1 to 12, the virus reproduction rate moved from 0.88 to 0.96.
For the record, as for the R0, when the indicator is below 1, it means someone sick contaminates less than 1 person, but if this indicator goes above 1, it means someone sick contaminates over 1 person, which is another signs the epidemic grows.
A pandemic that goes on and speeds up across the world
If the virus is slowing down in France, it is far from being the case in the rest of the world. Over 120,000 deaths in the United-States, new clusters reported in China, Italy, Portugal, partial lockdown again in Germany… As many forerunning signs that a second epidemic wave is possible, especially since borders are reopening on July 1 for countries external to the Schengen area.
Other countries have been hit by a second wave already, like Iran, India, and even South Korea that admitted on Tuesday June 23, they were in the midst of a new contamination wave, with 50 cases reported per day.
Covid-19, a season-sensitive virus?
“If we look at the history of the great respiratory virus pandemic, we notice than eight out of ten dwindle spontaneously in European countries in the summer. Yet, five out of ten are recurring in the Fall”. Words pronounced earlier in June by Scientific Committee President Jean-François Delfraissy, that are far from being reassuring. A virus that could recur as a second wave later this year? This is the hypothesis many doctors and scientists are asserting, explaining the virus is highly sensitive to the heat, and it develops more easily in cold or humid period.
An hypothesis that could be explained by the fact the disease spread through droplets and they are “surviving longer in the open air when it is cold, and immune defenses are weakened in the winter” as our peers from Ouest France explain. Another explanation: the virus is deteriorating more easily on hot surfaces, “the layer of protective fat that contains them drying faster” to quote our peers. A seasonality that is still sparking debates, and that will find answers in the different studies on the matter.
Back in May, the European Center for Disease Prevention and Control (ECDC) already signaled Europe should brace itself for a second wave. Head of the ECDC Andrea Ammon said it was not about if it will happen, but when and how big it could be. The perspective of the resurgence of the virus was even the main topic to put up an emergency re-containment plan by the French government.