US health officials said Tuesday that the effectiveness of the Pfizer and Moderna vaccines against the Delta type of coronavirus has fallen to 66%. For epidemiologist Martin Blacher, a guest at CNEWS, this means that herd immunity may not be achieved.
66% is not very important. This shows that collective immunity, which we have been talking about for a very long time, is almost impossible to achieve, as the specialist said on Wednesday morning in the Hour of Professionals.
Remember that herd immunity is the percentage of a population that is immune or protected from infection against which a virus cannot spread. When the population is vaccinated appropriately (because they have already been infected or thanks to the vaccine), the virus disappears because it can no longer infect new people. So the government’s strategy is to vaccinate as many people as possible, to quickly achieve herd immunity and thus put an end to the epidemic.
Immunization of people at risk as a priority
However, US health officials reported that the Pfizer and Moderna messenger RNA vaccines were only 66% effective against Delta-type infections, while the rate rose to 91% when this variant was not prevalent. However, Martin Blacher remembers one important point: “It is effective in transmitting the virus. It is not at all effective in protecting against disease.”
This means that vaccines are less effective in stopping transmission of the virus, but they are still very effective in fighting severe forms of Covid-19. The idea that everyone should be vaccinated and that the cycle of the virus will disappear with this vaccine is one that is advancing more and more. But the idea is to vaccinate everyone so that as few people as possible can get vaccinated. “hospital”.
According to Martin Blacher, there is no urgent need to vaccinate children. It is important to continue to focus on the population most vulnerable to severe forms of the disease so that intensive care services are not saturated again. Today, Tuesday, the Supreme Health Authority published a statement in this direction, recommending a third dose of the vaccine for people over 65 years old.