Only half, as a precaution.
This Wednesday, the United States Medicines Agency (FDA) ruled on the booster doses of the Covid-19 Spikevax vaccine, developed by Moderna, one month after the authorization of the Pfizer vaccine booster.
Americans over 65 or at high risk of developing severe forms of Covid-19 will be able to receive a new injection, but only with a half-dose, the FDA said in a statement.
According to the manufacturer, injecting half of a dose six months after completing a full vaccination schedule would minimize the risk of side effects, while maintaining satisfactory efficacy against severe forms of Covid-19.
In France, no Moderna recall until further notice
Since October 15, the French government has temporarily stopped booster injections with this messenger RNA vaccine, due to a greater risk of developing side effects than with a third dose of the Pfizer vaccine.
The French health authorities are based on a study having "established that men injected with the Moderna vaccine and aged less than 30 years had a slightly increased risk of developing inflammation of the myocardium".
The FDA is therefore also taking its precautions, even if these side effects remain very infrequent.
According to a note from the Directorate-General for Health, the European Medicines Agency must decide at the end of October on the validity of the data provided by Moderna, with a view to adopting the same strategy in Europe.
The FDA has also cleared Johnson & Johnson vaccine recalls for all people 18 and over.
This vaccine is considered to be relatively less effective than messenger RNA vaccines if injected as a single dose.
Finally, the FDA also authorizes the realization of a third dose with any authorized vaccine against Covid-19, even if it is different from the vaccine received in the first place.
