Data Does Not Support Need for COVID-19 Vaccine Boosters: Experts | Health Info

By Steven Reinberg, Health Day reporter

MONDAY, September 13, 2021 (HealthDay News) – Booster shots of the COVID-19 vaccine may not be necessary for most people, according to a major international journal.

The review – conducted by a team including scientists from the World Health Organization and the United States Food and Drug Administration – concluded that current vaccines are sufficiently effective against severe COVID-19, even from Delta variant, and that booster injections are unnecessary.

The results, published on September 13 in The Lancet, are based on a review of all available published literature and clinical trial results.

“The vaccines currently available are safe, effective and save lives,” said study co-author Dr Soumya Swaminathan, chief scientist at WHO.

“While the idea of ​​further reducing the number of COVID-19 cases by boosting immunity in those vaccinated is attractive, any decision to do so should be evidence-based and consider the benefits and risks to them. individuals and society, ”she said in a newspaper. Press release. “These high-stakes decisions should be based on solid evidence and international scientific discussions.”

According to the review, the vaccines were 95% effective against serious illnesses of the Delta and Alpha variants, and over 80% effective in protecting against infection with these variants.

According to the review, vaccines are less effective against asymptomatic illnesses or transmission than against serious illnesses. He added that unvaccinated people are the main drivers of transmission and are at the greatest risk of serious illness.

“Taken as a whole, the studies currently available do not provide credible evidence of a substantial decline in protection against serious disease, which is the primary goal of vaccination,” said lead author Dr Ana Maria Henao-Restrepo, doctor at the WHO Initiative. for vaccine research.

She said the limited vaccine supply would save the most lives if it was made available to unvaccinated people at risk of serious illness.

“While a gain may ultimately be achieved through stimulation, it will not outweigh the benefits of providing initial protection to unvaccinated people,” added Henao-Restrepo. “If the vaccines are deployed where they would do the most good, they could hasten the end of the pandemic by inhibiting the future evolution of the variants. “

Although antibodies in those vaccinated decline over time, the authors noted that it does not predict a lack of protection against serious illness.

Protection against serious illness is not only due to antibody responses, which can be short-lived for some vaccines, but also memory responses and cellular immunity, which are longer-lasting, the researchers explained. If recalls are necessary, they would be in circumstances where the benefits outweigh the risks.

However, even without loss of efficacy, the increasing success of vaccine delivery to large populations will result in more widespread vaccination, the researchers said. As a result, more cases that do occur would be less severe breakthrough infections, especially if the vaccination causes people to change their behavior.

But, they added, the ability of vaccines to elicit an antibody response against current variants indicates that these variants have not yet evolved so much that they are likely to escape vaccine protection.

If boosters are needed, the researchers said, they would most likely be developed against specific variants not covered by current vaccines. This strategy is similar to that of influenza vaccines, which changes as influenza strains change from year to year.

THE SOURCE: The Lancet, press release, September 13, 2021

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