Vaccine boosters for COVID-19 are not required for the general population at this stage even as the highly contagious Delta variant is leading to a spike in fresh cases the world over, a report by an international group of scientists has said.
The vaccines currently in use are "effective against severe disease, including that caused by the Delta variant", the report published in the medical journal The Lancet said.
Studies have shown that vaccines have 95 percent efficacy against severe disease, including the Delta and the Alpha variant, and about 80 percent efficacy against other infections from these variants.
The expert panel included the World Health Organization's chief scientist Soumya Swaminathan, researchers Ana-Maria Henao-Restrepo and Mike Ryan.
According to scientists, even if the effectiveness of the vaccine wanes over time against mild disease, protection against severe disease will continue to persist. "This effect could be because protection against severe disease is mediated not only by antibody responses, which might be relatively short-lived for some vaccines but also by memory responses and cell-mediated immunity, which are generally longer-lived," said study co-author Soumya Swaminathan.
The scientists agreed that immunocompromised individuals can benefit from an additional dose of the vaccine even now.
Risks of a Third Dose
Scientists say the use of boosters now could lead to side effects such as myocarditis, which is a rare heart inflammation condition.
Focus on Have-Nots
"Taken as a whole, currently available studies do not provide credible evidence of substantially declining protection against severe disease, which is the primary goal of vaccination," Aljazeera quoted lead author Ana-Maria Henao-Restrepo of the WHO as saying.
According to her, it is now necessary to focus on providing vaccines doses to people around the world who are yet to receive their first jab. "If vaccines are deployed where they would do the most good, they could hasten the end of the pandemic by inhibiting further evolution of variants," she said.
The US government is awaiting the nod of health regulators to offer booster shots to fully vaccinated individuals from next week. A panel of experts is due to meet on September 17 to discuss additional doses of the Pfizer-BioNTech shot.
Also read: WHO's approval for Covaxin likely this month
Even as the US and UK plan for a third dose, France has already started inoculating the elderly and those with compromised immunity with a third shot. After inoculating about 2.8 million people with a third dose since August, Israel is preparing for the fourth round of COVID-19 shots if required.
"We don’t know when it will happen; I hope very much that it won’t be within six months, like this time, and that the third dose will last for longer," Nachman Ash, Israel’s health ministry director-general, said in a recent interview.
WHO chief Tedros Adhanom Ghebreyesus has requested countries to refrain from doling out extra COVID-19 vaccines until the end of the year.