It is expected that the Pfizer and Moderna vaccines will remain very effective against two variants of the coronavirus that were first isolated in India, according to new research conducted by American scientists. The study was carried out on lab cells at the Grossman School of Medicine and the Langone Center at New York University, and its results are preliminary as they have not yet been published in a peer-reviewed journal.
Lead researcher Nathaniel "Ned" Landau stated, "What we found is that the antibodies from the vaccine were slightly weaker against the variants, but not to the extent that it would make us think that it would have a significant impact on the protective capacity of the vaccines."
Researchers initially took blood samples from individuals vaccinated with one of the two dominant vaccines in the United States, which have been administered to more than 150 million Americans. They then exposed these samples in the lab to viral particles containing two mutations in the virus spike, one specific to variant "B.1.617" and the other to variant "B.1.618," which were first isolated in India. The mixture was then exposed to cultured cells in the lab to see how many would become infected.
The researchers found a decrease of about four times in the amount of neutralizing antibodies produced by the immune system to prevent pathogens from invading cells for the first variant and about three times for the second variant. Landau said, "In other words, some of the antibodies no longer work against the variants, but we still have plenty of antibodies that do."
He added, "There are enough of those that work to the extent that we believe the vaccines will be largely protective," as the overall levels of antibodies are still much higher than those found in samples taken from individuals who recovered from infection with the non-variant version of the virus. However, this type of lab experiments cannot predict what happens in the real world, so further studies are needed.
The team concluded, "Our results give us confidence that current vaccines will provide protection against the variants identified so far." However, they did not rule out the possibility of newer, more vaccine-resistant variants emerging, which underscores the importance of widespread vaccination at the global level.
