Posted ,
Reading 1 min.
A new US study suggests that the effectiveness of the third dose of Covid vaccine begins to decline after 4 months.
Will a fourth dose be needed and if so how soon? The question is already being studied by scientists. A new US study conducted by the US Centers for Disease Control and Prevention (CDC) looked at the time to protection provided by the third injection with messenger RNA vaccines.
A decrease in effectiveness after 4 months
The effectiveness of RNA vaccines with a booster dose was well confirmed during this study, the protection offered by the second dose having been undermined by the arrival of the Omicron variant. But for how long ? To find out, the study group studied data from emergency room visits and hospitalizations indicative of severe forms, in 14 medical centers in the USA between August 2021 and January 2022. After two months, immune protection against Covid-19 after the booster dose by RNA vaccine is estimated between 87% and 91% then four months later it begins to drop from 66% to 78%.
These data therefore only concern efficacy on severe forms, the impact on contamination in general still remains inconclusive. Nevertheless, they could be enough to convince the scientific councils and in particular those which surround the government to motivate another dose of booster in several months for the people most at risk.
Consult a GP online
No 4th dose in France for the moment
To date, the question of setting up a second Covid vaccine booster or 4th dose of vaccination in the case of a classic vaccination scheme in a non-immunocompromised person has not been adopted in France.
In one notice of January 19 the Council of the vaccine strategy, seized on the question rejected the idea, for the moment. “The Council considers that the available data do not currently call for the implementation of a second vaccination booster.