What are the side effects ?

A US study published at the end of September showed that the side effects observed after a booster dose of an anti-Covid vaccine from Pfizer and Moderna were largely “similar” to those seen after the second.

This data was collected from several thousand people who received a third dose of these treatments between mid-August and mid-September, when it was allowed for some immunocompromised people in the country.

The study shows that “booster doses are currently well-tolerated,” Rochelle Wallinsky, director of the Centers for Disease Prevention and Control (CDC), said at a news conference.

“The frequency and type of side effects were similar to those seen after the second doses of the vaccine, and were mostly mild or moderate and short-lived,” she added.

Characters close to those after the second injection

The data is based on about 20,000 people who signed up for the (v-safe) app, and who filled out a questionnaire after the injection.

Among those who completed this questionnaire after each of the three doses, nearly 79% reported a local reaction after the third injection (pain at the site of the bite, etc.), and 74% reported a so-called systemic reaction, i.e. to say affecting the whole body ( Tired …).

After the second injection, these numbers were 78% and 77%, respectively, which are very similar.

Of the more than 20,000 people, about 28% said they were unable to go about their usual daily activities after the third dose, most of the time the day after the injection.

In addition, the study does not necessarily focus only on people who are immunocompromised, but other people who may also have received a third dose by circumventing recommendations at the time, the CDC specified.