Vaccines need to be updated to combat Covid variants: Experts

Although current Covid vaccines provide a high level of protection against severe disease and death caused by variants of concern (VOC), health experts believe that new vaccines that can prevent infection and transmission are needed.

All major Covid 19 vaccines have been developed against the original strain of SARS CoV-2. While these have proved highly effective, they need to be reinvented to combat newer variants like Omicron which has the potential to escape vaccine immunity.

A booster dose, every six months may not be a sustainable idea, the experts contended.

"The current vaccines do protect a person from severe illness and death, but we need to update the vaccines so as to protect people from getting infected as well as reduce the chances of transmission. Since the virus mutates very frequently and there is the presence of many strains, we cannot rely on the same vaccine as a booster dose," Dr Akshay Budhraja, Senior Consultant, Respiratory and Sleep Medicine, at Aakash Healthcare, told IANS.

In the wake of the Omicron variant, several vaccine makers including Pfizer, Moderna, and AstraZeneca said they are making variant-specific vaccines that can be used as booster doses.

According to Pfizer CEO Albert Bourla, its Omicron specific vax will be ready by March, while Moderna CEO Stephane Bancel said the company will soon enter clinical trials for Omicron vaccine.

The development of boosters are based on several studies which showed that two-dose vaccines may not be enough against newer variants, while third doses may help prevent severe infections.

The rise of Omicron has only increased the demand for booster shots. India has also rolled out booster doses for people over the age of 60 and healthcare workers.

There have also been calls for a second shot of boosters, as the booster dose's effectiveness may also wane. While Israel started it, other countries including the UK, Germany, and France have plans.

But, the World Health Organisation called the vaccine manufacturers to work towards creating longer-lasting Covid vaccines that are effective against future strains, instead of focusing on rolling out regular boosters, the Guardian reported.

The agency's Technical Advisory Group on Covid-19 Vaccine Composition (TAG-CO-VAC) released a report this week saying that planning to regularly roll out Covid boosters is not sustainable.

Oxford vaccine expert Sir Andrew Pollard, also echoed the concern and recently said that regular booster doses every four-six to fight Covid may not be a sustainable way to prevent Covid infections.

"Administering booster vaccines to everyone every six months was 'not sustainable'," Pollard was quoted as saying to the Daily Mail.

"We can't vaccinate the planet every four-six months. It's not sustainable or affordable. In the future, we need to target the vulnerable," said Pollard, who was chief investigator of the Oxford Covid vaccine trials and director of the Oxford Vaccine Group, which developed AstraZeneca's jab.

According to Pollard, future immunisation drives should target the most vulnerable, rather than all adults.

"The existing vaccines can be improved in a variety of ways and adapted to what the needs are. Within three to five years, scientists will be looking at developing vaccines that cover and protect against multiple variants of SARS CoV-2, and even against multiple coronaviruses," Dr Alpana Razdan, Microbiologist, Vice President and Head of Lab Services, Genestrings Diagnostic, told IANS.

"With improved vaccines, we may be able to improve the effectiveness of global vaccination and make sure that people everywhere in the world, including children and those who are clinically vulnerable, are protected," she added.