Immunity

 source: Le Journal de Montreal/AFP

Translation: GoogleTranslate/doxa-louise

COVID-19: WHO more pessimistic about the ability of vaccines to end the pandemic

COPENHAGEN, Denmark | The director of the WHO in Europe was more pessimistic on Friday about the ability of a high vaccination rate to stop the COVID-19 pandemic on its own, due to variants that have reduced the prospect for collective immunity .

With an increased probability that the disease will remain endemic without being eradicated, Hans Kluge called during a press conference to "anticipate in order to adapt our vaccination strategies", in particular on the issue of additional doses.

In May, the UN health official said that "the pandemic will  be over when we have reached a minimum vaccination coverage of 70%" of the world population.

Asked whether that goal still holds or should be raised, Kluge pointed out that the newer, more contagious variants, primarily Delta, have changed the rules of the game.

At the time, even though the variant initially detected in India was already rampant, "there was no such emergence of more transmissible and more viral variants," he argued.

“So I believe this brings us to the point where the primary goal of vaccination is first and foremost to prevent severe forms of disease and mortality,” Kluge said.

"If we consider that COVID-19 will continue to mutate and stay with us, like the flu, then we must anticipate how to gradually adapt our vaccination strategy to endemic transmission, and acquire very valuable knowledge on the impact of using additional doses , ”he added.

According to epidemiologists, it now seems illusory to achieve collective immunity only through vaccines, but these remain crucial to contain the COVID-19 pandemic.

A very high level of vaccination also remains essential "to reduce the pressure on our health systems which desperately need to treat diseases other than COVID-19", stressed Mr. Kluge on Friday.

Now dominant, the Delta variant is judged to be 60% more transmissible than the previous one (Alpha) and twice as much so as the historical virus. However, the more contagious a virus, the higher is the threshold necessary for collective immunity, that is to say the threshold of immunized people beyond which the epidemic stops. This can be obtained through vaccines or natural infection.