Following the FDA's rejection of the wider use of the third dose among people aged 16 and older, leading infectious disease specialist Dr Anthony Fauci stated on Sunday that booster shots of COVID-19 vaccines will soon be required for people to get optimum protection against COVID-19.

Dr Fauci remarked, "I'm favourably disposed to boosts based on the waning of immunity, as we're seeing very, very clearly in the data in the US and even more dramatic data from our Israeli colleagues."

"There is some indication of waning in the UK, which is the reason the UK has or will soon be vaccinating people 50 years of age and older, as well as healthcare providers and those who are immunocompromised," he added.

According to a Pfizer study, published in the New England Journal of Medicine, found that the rate of infection was eleven-times lower and the rate of severe disease approximately twenty-times lower in individuals who received a booster dosage compared to those who had only two doses.

It has been reported by Moderna's mRNA vaccine against COVID-19 only lasts about six months, making the case for booster shots quite strong.

Many countries, including Israel, the UAE, Russia, France, Germany and Italy, have already begun administering booster doses. However, other scientists, including those at the World Health Organization, are opposed to administering a third COVID shot.