Should we fear the arrival of a second wave?
“It is entirely possible,” replies Professor Yves Buisson, epidemiologist and president of the Covid-19 group of the Academy of Medicine, which we have joined. While there has been a gradual decline in the coronavirus epidemic in France, since April 20, the prospect of a second wave is far from being dismissed by the scientific community. If the northern hemisphere seems to be slowly getting rid of the virus, the southern hemisphere, and in particular the countries of Latin America, have been hit hard by the contagion. For all specialists, it is this “swinging” effect of the virus between these two hemispheres that worries. A movement already observed with the flu which progresses during the fall season and with the arrival of the first days of winter. “This is a seasonal phenomenon since we see that Brazil is currently hard hit while temperatures on this part of the globe are cooler,” said the epidemiologist. It is therefore not impossible that the northern hemisphere will once again be affected by a second wave with the arrival of autumn.
How long is a healed person immune?
A person who got rid of the coronavirus develops antibodies after 15 days. We then see these neutralizing antibodies appear in her, but we do not yet know how long this immunity can last. For SARS (severe acute respiratory syndrome), which caused several thousand deaths worldwide between 2002 and 2003, these protective antibodies had a duration of 2 to 3 years. For the Covid-19, scientists do not have enough perspective to precisely define the duration, over time, of the protective shield. On the other hand, we know that a person healed from the Covid is no longer contagious. It remains to be seen for how long. For example, 160 caregivers from two Strasbourg hospitals who had been infected with the coronavirus were tested. They had developed light forms, without any hospitalization. One month after the disease, the presence of antibodies was indisputable: “Antibodies have been found in almost all of them: 159 out of 160”, explained recently, Professor Arnaud Fontanet of the Pasteur Institute who is conducting this study. “And, more interestingly, we were looking for neutralizing antibodies which we know are protective against, for example, reinfection. And there, from one month, we find them in 98% of people who had been infected with SARS-CoV-2. These results are indeed good news. “
A vaccine for 2021?
The first vaccines against Covid-19 are expected in the first half of 2021. To date, 150 teams around the world are working on the miracle cure, including the Institut Pasteur. A dive into the unknown for these researchers who have to go through several validation phases including the pre-clinical and clinical trials which take a long time. In addition, a clinical trial using plasma began in early April. “This clinical trial consists of the transfusion of plasma from cured patients of Covid-19, containing antibodies directed against the virus, and which could transfer this immunity to a patient suffering from Covid-19”, explained in a press release the Assistance public-Hospitals of Paris, the French Blood Establishment and the National Institute of Health and Medical Research. This experiment, called Coviplasm, gave rise to samples in the Grand-Est and in Bourgogne-Franche-Comté from around 200 patients who had been cured for at least 14 days. “An initial assessment can be made two to three weeks after the start of the clinical trial,” they said. Similar tests are underway in China and the United States.
Coronavius: these billions in spades
This Wednesday 27 May, the President of the European Commission, Ursula von der Leyen, will present to the European Parliament a recovery plan of up to € 1 trillion, intended to overcome the crisis caused by the coronavirus. This plan is in addition to the 500 billion euros released by Emmanuel Macron and German Chancellor Angela Merkel last week. In the United States, President Trump has signed a 2,000 billion dollar (1,842 billion euro) economic stimulus package to support the industry.
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