The EMA announced on Monday that its human medicines committee (CHMP) has concluded that an extra dose of the COVID-19 vaccine Comirnaty (BioNTech/Pfizer) may be given to all over-18s. It is studying data to see whether a third Moderna jab could also be administered as a booster vaccine.

The extra jab could be given a least six months after the individual received their second dose of the vaccine.

“The CHMP has evaluated data for Comirnaty showing a rise in antibody levels when a booster dose is given approximately 6 months after the second dose in people from 18 to 55 years old,” read the EMA statement.

“On the basis of this data, the Committee concluded that booster doses may be considered at least 6 months after the second dose for people aged 18 years and older.”

It also concluded that an extra dose of the Pfizer or Moderna COVID-19 vaccines may be given to people with severely weakened immune systems, at least 28 days after their second dose.

Each country in the EU and has implemented its own policy towards Covid-19 vaccines and the goes for booster shots. Certain countries have already began booster campaigns for elderly residents with weakened immune systems.

“At national level, public health bodies may issue official recommendations on the use of booster doses, taking into account emerging effectiveness data and the limited safety data,” the EMA said.

“The implementation of vaccination campaigns in the EU remains the prerogative of the national immunisation technical advisory groups (NITAGs) guiding the vaccination campaigns in each EU Member State.

“These bodies are best placed to take into account the local conditions, including the spread of the virus (especially any variants of concern), the availability of vaccines and the capacities of national health systems.”

The EMA said there was no know side effects following a booster jab.

“The risk of inflammatory heart conditions or other very rare side effects after a booster is not known and is being carefully monitored. As for all medicines, EMA will continue to look at all data on the safety and effectiveness of the vaccine,” the regulator added.