Like an air of ” déjà vu “. As China lifts its policy “zero Covid” and health restrictions, it allows its inhabitants to travel abroad from January 8. But many countries have already imposed tests on travelers coming from the Middle Kingdom in the face of the explosion of Covid cases in the country.
With its management of the Covid, a politically and economically weakened China
By recalling the memories of the start of the Covid epidemic and the panic that had affected the world at the end of 2019, these countries – in particular the United States, Italy or India – want to first avoid a new wave of Covid. But also the new variants that may appear in China where the explosion of Covid cases could create potential breeding ground for their emergence.
On this last point, the various experts all agree that the situation in China is a potential source of new variants. But opinions differ as to the potential variants and the protocol to follow to minimize the risks.
“It’s phenomenal! »
Each new infection increases the chances that the virus will mutate, estimates Antoine Flahault, director of the Institute of Global Health at the University of Geneva. “The fact that 1.4 billion people are suddenly exposed to SARS-CoV-2 obviously creates conditions conducive to the emergence of variants”he told AFP on Thursday, December 29.
The virologist Christian Bréchot, former director of the Institut Pasteur, confirms to the ” Parisian » : “Do you realize: until then, we were 670 million in the world to have been infected with Covid since the start of the epidemic. There, suddenly, in three or four weeks (China lifted its restrictions on December 7) at least 250 million Chinese were infected. It’s phenomenal! »
Soumya Swaminathan, who served as the World Health Organization’s (WHO) chief scientist until November, also said much of the Chinese population was vulnerable, in part because many older people have not been vaccinated. “We must closely monitor any emergence of worrying variants”she told the newspaper’s website ” Indian Express ».
BF.7, a “hypercontagious” variant of Omicron in China
In total, the virus control institute in China has detected more than 130 new sublineages of the Omicron variant in the past three months. Antoine Flahault even speaks of” a soup “ over 500 new Omicron subvariants identified.
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Among them, BA.5.2 and BF.7 are the main strains of Omicron detected in China. The latter is currently marginal in France. “What is certain is that BF.7 is hypercontagious. Its R0 is greater than 10 (an infected person contaminates at least 10), compared to 5.6 for the Delta variant. [Mais] we have no evidence of greater dangerousness”explains Christian Bréchot in ” The Parisian “.
“Today, none of these variants appear to pose particular new risks of more severe symptoms, but new variants may in the near future.”concluded Antoine Flahault.
Border testing, variant detection and vaccination
So what to do? For Antoine Flahault, it is absolutely necessary to quickly detect new variants: “If we succeed in sampling and sequencing all the viruses identified in all travelers from China, we will know almost immediately if new variants are emerging and spreading” in the country, he explained.
In this context, Christian Bréchot recommends following the decisions of Japan or South Korea and introducing test measures at the borders. These controls “may limit the introduction of the virus”estimates the virologist for whom “prevention and monitoring are the key words”.
An opinion that does not share Bruno Lina, virologist at the Lyon University Hospital and member of the Committee for monitoring and anticipating health risks (Covars), who reminds franceinfo that “no control measure has ever prevented the arrival of variants on European territory”. For him, the priority must be established in two points: get information » of Beijing and continue to vaccinate. “The variants circulating in China are the same as those circulating in France,” so vaccines are “adapted to circulating viruses”he presses.
