Over the last seven days, Public Health France recorded 287,604 new cases of Covid-19 and 2,219 new hospitalizations per day on average in the territory. In its weekly epidemiological update of January 6, thenational public health agency note indeed a “extremely marked acceleration of the circulation of Sars-CoV-2 linked to the very rapid progression of the Omicron variant”. Between December 27 and January 2, “74% of tests screened showed a profile compatible with the Omicron variant “.
Faced with this fifth wave of the epidemic, the government did not choose strong restrictive health measures, but rather to toughen the health pass by transforming it into a vaccination pass, or to encourage more teleworking. The executive, however, denies “let the virus go”. Guest of franceinfo on Wednesday January 12, the Minister of Health Olivier Véran declared: “We are not trying to let this variant circulate. […] Now it’s so contagious that yes it is circulating. “ What if, however, the Omicron variant contaminations were good news for our herd immunity? In any case, this is what some scientists and doctors view with caution. So, should the Omicron variant be allowed to circulate to end the health crisis as quickly as possible?
More contagious than the Alpha and Delta variants, Omicron however causes fewer serious forms. This is because the Omicron variant, unlike Delta, rather causes infections in the upper respiratory tract. That is, the infection is concentrated more in the nose, throat and sinuses. The Delta variant, on the other hand, causes lower respiratory infections, affecting more of the lungs. It therefore generates more serious forms. According to Yves Buisson, epidemiologist and president of the Covid cell of the National Academy of Medicine, this localization of the virus in the mucous membranes of the nose and mouth explains its great contagiousness, but could also prove to be good news for the acquisition. collective immunity.
“Omicron improves protection against the virus, makes it stronger and more lasting, analyzes the doctor. It triggers protection of the mucous membranes in the respiratory tract, nose, throat and mouth. Vaccines stimulate antibodies, but the virus has time to multiply in the upper airways. If we have extra protection for the mucosa, it’s much better. “ Vaccines against Covid-19 by the nasal route are also currently being tested, with the objective of being marketed in 2023.
The European Medicines Agency (EMA) is also relatively optimistic about the Omicron variant. Marco Cavaleri, head of vaccine strategy at the EMA, said on Tuesday that the Omicron variant could make it possible to move from a pandemic phase to an endemic phase of the disease, in other words a trivialization of Covid-19, in the manner of ‘a viral illness like the flu. “With the increase in immunity in the population, and with Omicron, there will be a lot of natural immunity in addition to vaccination. We will move quickly towards a scenario that will be closer to endemicity.”, judged the European expert. However, he also recalled that “we must not forget that we are still in a pandemic”, therefore remain cautious.
A caution shared by epidemiologists contacted by franceinfo. As Mahmoud Zureik, professor of public health and epidemiology at the University of Versailles Saint-Quentin-en-Yvelines and director of Epi-Phare, points out, Omicron remains a recent variant. “We are not immune to a good surprise, but it is not yet a trivialized virus like the common cold. We must not draw conclusions too quickly. Omicron, it has not been even two months since “It is there. We do not yet know its consequences in the medium term. This calls for the greatest vigilance and caution before letting it circulate freely. We cannot take bets on things like that.”
“The duration of the immunity conferred by Omicron is not well known. The pros and cons have to be weighed very patiently due to the lack of scientific data. There are still too many unknowns to make an informed choice.”, replies Emmanuel Rusch, president of the French Society of Public Health (SFSP) and doctor at the CHRU of Tours.
“To let the virus circulate is to play with fire”, Yves Buisson alert. “This Omicron variant gives much less severe forms than the Delta. But, as it multiplies faster, we will always have resuscitation. It is a risk that should not be taken.” The epidemiologist also points out that the onset of the annual flu epidemic “brings hundreds of patients into intensive care every year”. According to him, “If we drop all barrier measures now, we will see damage.”
For Emmanuel Rusch, the question of promoting the circulation of the Omicron variant must weigh on the scales “risk-benefit”. “The observation is that the virus is circulating widely today. The fact remains that attempting to limit its circulation allows the overload to be spread for health establishments. Relaxing all measures would lead to additional tension for them.” However, as of January 12, France had 23,889 people hospitalized, including 3,985 in critical care.
According to the latest models from the Institut Pasteur (PDF), stopped on January 7, “dIn all scenarios, peak hospital admissions are expected in the second half January, with a maximum impact on bed occupancy at the end of January-during February. ” In the scenarios considered most probable by the modellers and according to the rate of transmission of the virus, there would be 2,500 to 3,600 hospitalizations per day on average at the peak of this wave. To cope, the hospital would then need 17,000 to 23,000 conventional hospital beds and 3,900 to 4,700 critical care beds.
Mahmoud Zureik is also not in favor of relaxing health measures. He reiterates the importance of limiting the circulation of the virus, in order to protect vulnerable people. “The best way to protect vulnerable people is to reduce the spread. Significant circulation further exposes people with underlying conditions, the elderly or the immunocompromised. These frail people, even with the vaccine, could develop diseases. severe forms with Omicron. Collective immunity is good, but not for those who are going to the hospital or who are going to die. “
“Omicron, with its extraordinary and unprecedented level of transmissibility efficacy, will eventually find just about everyone. Unfortunately, those who are not vaccinated will suffer the full brunt of the consequences,” Anthony Fauci, American immunologist and White House adviser, warned Tuesday. However, the scientist provided a silver lining, saying: “We are not at the point where we can say in an acceptable way ‘living with the virus’, in part because of the pressure currently on the health care system. But I think we will get there.” And Anthony Fauci to explain that“a combination of good basic immunity and the possibility of treating a person at risk” could allow a transition for “living with the virus”.
Natural immunity, in particular thanks to the protection of the mucous membrane conferred by contamination by Omicron, is indeed a hope that the number of cases and severe forms of Covid-19 will decrease. For Yves Buisson, Omicron “has the capacity to make a kind of natural reminder”, but allowing the variant and therefore the virus to circulate remains too risky as long as the population is not widely vaccinated. “If the entire population were vaccinated and then contaminated with Omicron, we could envisage an end to the crisis. With compulsory vaccination from May-June, with 90-95% of the total population vaccinated, the risk would have been much lower. to let the Omicron variant run. However, we still have nearly a quarter of the population that is not vaccinated “, estimates the epidemiologist. According to Public Health France, as of January 11, 77.6% of the total French population is vaccinated with at least two doses. “If the entire population were vaccinated and then contaminated by Omicron, we could consider a way out of the crisis”, judge Yves Buisson. Without this vaccination coverage, it therefore seems premature to consider relaxing health measures to play the collective immunity card.
Emmanuel Rusch recalls that in addition to the Omicron variant, “the Delta variant continues to circulate”. According to Public Health France, on January 9, 11% of the tests screened presented the L452R mutation, characteristic of the Delta variant. Reducing health measures to allow the Omicron variant to circulate would result in free circulation of the Delta variant, responsible for more serious forms, hospitalizations and visits to intensive care and intensive care. In order to avoid further overloading hospitals and to protect vulnerable people, Yves Buisson therefore concludes: “We must maintain the barrier measures. We cannot prevent Omicron from spreading, but we must not make its job easier.”