The COVID vaccines have proven to be highly protective against the novel coronavirus, but nothing is ever 100 percent foolproof—especially when it comes to the coronavirus, which has evolved and mutated over the course of the past year and a half. Health officials and experts have called out several variants of concern, including a variant that originated in India and is potentially more transmissible and more likely to bypass current vaccines. Now, new research has shown that the India variant may be resistant to one of the three U.S.-approved vaccines in particular.
The new study, published on June 3 in the medical journal The Lancet, shows that people who got the Pfizer vaccine produced fewer antibodies against the India variant when compared to other strains of the virus. The researchers analyzed blood samples from 250 participants who received either one dose or two doses of the Pfizer vaccine. They then compared the antibody responses against five different COVID strains, including three variants of concern: India variant B.1.617.2, South Africa variant B.1.351, and U.K. variant B.1.1.7. According to their findings, people fully vaccinated with two doses of the Pfizer vaccine had fives times lower levels of antibodies against the India variant when compared to the original COVID strain, which current vaccines were targeted to fight.
When looking at those who received just one dose of the Pfizer vaccine, the study found that the antibody response was even lower. Compared to 79 percent who had sufficient levels of antibodies against the original strain, only 32 percent had an adequate response against the India variant after one dose.
The results are similar to another recent study, posted on May 27 on the website BioRxiv, which has not yet been peer reviewed. According to that study, people who received two doses of the Pfizer vaccine saw a three-fold reduction in antibodies targeting the India variant. In a statement, the May study's co-author, Olivier Schwartz, PhD, the director for France's Pasteur Institute, said the findings show that the variant "has acquired partial resistance to antibodies."
The June study's senior clinical research fellow Emma Wall, PhD, a University College London Hospitals consultant, said that more effort needs to be taken to help further protect those who get the Pfizer vaccine against the India variant. "The most important thing is to ensure that vaccine protection remains high enough to keep as many people out of hospital as possible," Wall said in a statement. "Our results suggest that the best way to do this is to quickly deliver second doses and provide boosters to those whose immunity may not be high enough against these new variants."
However, experts caution that these findings don't necessarily mean Pfizer's vaccine won't shield you at all from the India variant. More research needs to be done on exactly how antibodies correlate to immunity against the virus, as antibody levels alone do not indicate how effective a vaccine may be. Plus, lower antibody levels could still offer some protection.
"These data cannot tell us whether the vaccine will be any less effective at preventing severe disease, hospitalization, and death," Eleanor Riley, professor of immunology and infectious diseases at the University of Edinburgh, who was not involved in the study, told Sky News. "We need to wait for the actual data on these outcomes."