After a third booster dose of the Pfizer and Moderna coronavirus vaccines, the side effects observed are largely “similar” to those experienced after the second, according to a study by US health authorities, according to a study published on Tuesday.
These data were gathered from several thousand people who received a third dose of these remedies between mid-August and mid-September, when it was authorized for certain immunocompromised people in the country.
“Light and moderate” and “short-term” effects
The study shows that “the booster doses are currently well tolerated,” Rochelle Walensky, director of the Centers for Disease Prevention and Control (CDC), told a press conference. “The frequency and type of side effects were similar to those seen after the second doses of the vaccine, and they were mostly mild or moderate, and of short duration,” she added.
As of September 19, more than two million people had already received a booster dose in the United States, according to the CDC. The data released Tuesday is based on some 20,000 people who have registered on an application (v-safe), and who have completed a questionnaire after their injections.
Pain and fatigue
Among those who completed this questionnaire after each of the three doses, approximately 79% reported a localized reaction after the third injection (pain at the site of the sting, etc.), and 74% a so-called systemic reaction, that is, say affecting the entire body (fatigue …). After the second injection, these numbers were 78% and 77% respectively, so 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.
This data is not representative of the American population, however, warns the CDC, the majority of people registered on the app are white. In addition, the study does not necessarily focus only on immunocompromised people, other people who may have also received a third dose by circumventing the recommendations in place at the time, specify the CDC. US health authorities have, since the end of last week, expanded the population eligible for a third dose of Pfizer vaccine. Can now also receive it people 65 and over, and some at “risk” because of their state of health or because of a job exposing them particularly to the virus.