It appears that several new variants of the SARS-CoV-2 virus are capable of evading the effects of vaccines and immunity derived from previous infections, according to a study led by David Ho, the director of the Aaron Diamond AIDS Research Center at Columbia University. Ho called for the development of vaccines against the increasingly common new strains before it is too late to address their potential spread.
The new "COVID" variants, including BQ.1, BQ.1.1, XBB, and XBB.1, have evolved from the Omicron variant. They, like their predecessors, have mutations in the region of the virus that interacts with cells, making them highly transmissible. Unlike Omicron, there is no specific vaccine targeting them.
David Ho's study, which has not been published or peer-reviewed, found that patients who received two initial mRNA vaccine doses along with a booster had 37 to 55 times the neutralizing immunity against BQ.1 and BQ.1.1, and 70 times less immunity against XBB and XBB.1. Those who received two booster doses performed worse against BQ.1 and BQ.1.1, and significantly worse against XBB and XBB.1.
Individuals who received the Omicron shot as a second booster performed slightly better against all four variants, and those who received the original booster and were infected with the BA.2 variant performed better than any other group against BQ.1 and BQ.1.1, even if their performance against XBB and XBB.1 was significantly worse.
The Columbia University study did not compare unvaccinated patients who contracted any of the variants, although many previous studies have found that natural immunity alone was more effective in neutralizing the Delta variant of the coronavirus than vaccine-derived immunity alone. It has not been proven that the Pfizer or Moderna mRNA vaccines prevent the transmission of any of these variants, although they are believed to mitigate the severity of the disease.
David Ho acknowledged that science is playing catch-up, as COVID-19 vaccines are often rolled out when the targeted variant has already declined, and urged scientists to start animal trials for vaccines against the new variants now.
