Sunday 23 January 2022
- Advertisement -

Booster dose with existing vaccines bad idea, say WHO, EU regulator

Frequent Covid-19 booster shots may affect the immune system and may not be feasible, say experts at the EU while a WHO panel has called it an unviable strategy

While decision-makers in the Government of India have given a go-ahead to existing vaccines like Covishield made by AstraZeneca and Oxford University and procured and manufactured by the Serum Institute, defying the fact that the UK is not permitting it, now there are other experts in medicine who are saying it’s a bad idea. A panel of scientists at the World Health Organization (WHO) warned on 11 January that repeating booster doses of the original Covid-resisting vaccines is not a viable strategy against emerging variants and called for new jabs that better protect against transmission.

A WHO expert group that assesses the performance of Covid-19 vaccines said simply providing fresh jabs of existing Covid vaccines as new strains of the emerge was not the best way to fight the pandemic. “A vaccination strategy based on repeated booster doses of the original vaccine composition is unlikely to be appropriate or sustainable,” the WHO Advisory Group on Covid-19 Vaccine Composition (TAG-Co-VAC) said in a statement.

It said preliminary data had indicated the existing vaccines were less effective at preventing symptomatic Covid disease in people who have contracted the new Omicron variant, currently spreading like wildfire around the world.

However, protection against severe disease, which is what the jabs were especially intended to do, “is more likely to be preserved”.

The panel recommended developing vaccines that not only protect people against falling seriously ill but could also better prevent infection and transmission in the first place. “Covid-19 vaccines that have a high impact on the prevention of infection and transmission, in addition to the prevention of severe disease and death, are needed and should be developed,” TAG-Co-VAC said.

“Until such vaccines are available, and as the Sars-CoV-2 evolves, the composition of current Covid-19 vaccines may need to be updated, to ensure that (they) continue to provide WHO-recommended levels of protection against infection and disease by VOCs (variants of concern), including Omicron and future variants.”

Now, regulators also have warned that frequent Covid-19 booster shots could adversely affect the immune system and may not be feasible. Repeat booster doses every four months could eventually weaken the immune system and tire out people, according to the European Medicines Agency. Instead, countries should leave more time between booster programs and tie them to the onset of the cold season in each hemisphere, following the blueprint set out by influenza vaccination strategies, the agency said.

The advice comes as some countries consider the possibility of offering people second booster shots in a bid to provide further protection against surging omicron infections.

Earlier this month, Israel became the first nation to start administering a second booster, or fourth shot, to those over 60. The UK has said that boosters are providing good levels of protection and there is no need for a second booster shot at the moment, but will review data as it evolves.

Boosters “can be done once, or maybe twice, but it’s not something that we can think should be repeated constantly,” Marco Cavaleri, the EMA head of biological health threats and vaccines strategy, said at a press briefing on Tuesday. “We need to think about how we can transition from the current pandemic setting to a more endemic setting.”

The regulator also said at the briefing that oral and intravenous antivirals, such as Paxlovid and Remdesivir, maintain their efficacy against omicron.

The agency said that April is the soonest it could approve a new vaccine targeting a specific variant, as the process takes about three to four months. Some of the world’s largest vaccine-makers have said they are looking at producing vaccines that could target new variants.

Get in Touch

0 0 votes
Article Rating
Notify of

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Inline Feedbacks
View all comments

Related Articles


Get in Touch



Would love your thoughts, please comment.x
%d bloggers like this: