EMA Official Says Repeated Vaccination With COVID-19 Booster May Decrease Efficacy

The efficacy of booster doses against COVID-19 may dwindle due to repeated injections over short periods, as it takes time for the immune system to respond, Marco Cavaleri, the head of Biological Health Threats and Vaccines Strategy at the European Medicines Agency (EMA), said on Tuesday

MOSCOW (UrduPoint News / Sputnik - 18th January, 2022) The efficacy of booster doses against COVID-19 may dwindle due to repeated injections over short periods, as it takes time for the immune system to respond, Marco Cavaleri, the head of Biological Health Threats and Vaccines Strategy at the European Medicines Agency (EMA), said on Tuesday.

The EMA official already spoke against the use of additional boosters last week, citing potential concerns about immune system overload.

"The repeated administration of boosters with very short interval might reduce the level of antibodies that can be produced at each administration, as our immune system needs a certain amount of time to mature the response to the antigens it is presented with.

So, potentially, making the vaccination a little bit less efficient over time," Cavaleri said at a press briefing.

The regulator has already approved booster doses of the vaccines from Moderna and Pfizer/BioNTech, as well as using Johnson & Johnson's vaccine as a booster.