EU health agencies said on Wednesday there was no evidence to support the use of a fourth dose of COVID-19 vaccines developed by Pfizer and Moderna in the general population, but they recommend a second booster for people aged 80 and above.

There is no clear evidence in the European Union that vaccine protection against severe disease is waning substantially in adults with normal immune systems aged 60 to 79, the European Medicines Agency (EMA) and the European Center for Disease Prevention and Control (ECDC) said in a joint statement.

They cautioned, however, that it may become necessary to consider a fourth dose in this age group if the epidemiological situation changes.

Both agencies agreed a fourth dose can be given to adults aged 80 years and above.

That recommendation came a week after European health ministers urged the bloc's executive to back a fourth COVID-19 shot for people over 60 to boost immunity in the absence of vaccines that specifically protect against the Omicron variant.

A study from Israel has shown that senior citizens who received a second booster of the Pfizer–BioNTech COVID-19 vaccination had a 78 percent lower mortality rate from the disease than those who had only one.

The agencies said there was no conclusive evidence of "an added value of a fourth dose" in those aged below 60.

The agencies will consider the best timing for additional doses, possibly taking advantage of updated vaccines when re-vaccination campaigns start in autumn.