Is it necessary to inject Americans with a third dose of Pfizer's anti-Covid vaccine to better protect them against the virus?
Experts from the medical world are meeting on Friday to give their opinion on this divisive issue.
President Biden's administration announced in August that an anti-Covid vaccine recall campaign would be launched from September 20, for all Americans who received their second dose eight months previously.
This decision caught many experts by surprise, cautious about the possible side effects that this additional dose would generate, and critical at a time when many countries have only had access to a very limited number of doses.
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This mistrust has spread to the ranks of the United States Medicines Agency (FDA), which published a document tinged with caution before the meeting of its committee of independent experts on Friday.
“In general, the data indicates that the anti-Covid vaccines authorized in the United States still confer protection against severe forms of Covid-19 and death,”
the Agency said in a report. The experts on this committee - researchers, epidemiologists, infectious disease specialists - must decide whether they believe there is enough evidence on the effectiveness and safety of a booster dose. The recommendations of this committee are not binding, but it is very rare that they are not followed.
Any form of mistrust he could express would sound, however, like a blame directed at the Biden administration, which announced that it wanted to revaccinate all Americans even before consulting scientific agencies.
Two senior officials from the US Medicines Agency have already affixed their names to a letter published in
The Lancet
against a third dose
"at this stage of the pandemic"
.
Pfizer wants to convince
If these experts vote in favor of a booster dose for Americans, it will then be up to another committee, led by the main United States Federal Health Agency (CDC), to decide who should receive this vaccine. first, and when.
The group will meet on September 22-23.
The CDC has in the past ruled that adults over the age of 65, nursing home residents and healthcare professionals should be given priority.
Read alsoVaccine: the United States relies on a third dose to stem the epidemic
To convince of the need for this additional dose, Pfizer plans to cite studies that have shown decreased protection against infections a few months after the administration of the first two doses, according to company documents. However, a growing number of American studies show that two doses are sufficient to confer high protection against the serious consequences of the disease - albeit at slightly lower levels in the elderly.
Pfizer will also cite data showing that the boosters increase the level of antibodies against the Delta variant as well as studies conducted in Israel, which carried out a recall campaign, to support its arguments. The American Medicines Agency retorts for its part that all the studies are not necessarily reliable and judges that those emanating from research in the United States are
"likely to represent most faithfully the effectiveness of vaccines in the American population"
.