Winter is Coming

“The U.S. is going to see a winter surge in COVID infections,” predicts William Hanage, an epidemiologist at the Harvard T.H. Chan School of Public Health. “And I think that if nothing else changes BQ.1 and BQ.1.1 are likely to be very significant players”.

Two new omicron subvariants – BQ.1 and BQ.1.1 – are becoming dominant in the United States, causing fear of another COVID-19 surge as people prepare to gather for the winter holidays. These subvariants appear to be the most adept yet at evading immunity from vaccination and previous infection. 

Mutations in Spike Proteins

New mutations in the virus’s spike protein appear to make BQ.1 and BQ.1.1 as much as seven times more ‘immune evasive’ than past variants. Spike proteins are the antigens on the surface of the COVID-19 virus. A mutation in the spike protein is an issue because the body’s immune system creates antibodies to fend off foreignSARS-CoV-2 without background invaders specific to that antigen. Memory helper T and B cells then keep these antibodies within the body in the case of a secondary exposure, which would then cause a faster, stronger, and longer immune response. Because the spike proteins are mutated, the body needs to reenact the process of producing antibodies, which could take a long time to have a noticeable effect on the body’s immune system, therefore increasing concern for the individual’s overall health. 

A Closer Look at the Mutation (RBD)

The specific site of the mutation in the BQ.1 and BQ.1.1 variants is the receptor binding domain (RBD) which allows [the virus] to dock to body receptors to gain entry into cells and lead to infection; in other words, the RBD is the target of antibodies that deliver a potent immune response. Researcher Cao and his teamStruktura SARS-CoV 2 believe that the RBD mutations allow the variant to evade infection-blocking ‘neutralizing’ antibodies that were a response to previous COVID-19 vaccines and exposure to earlier Omicron variants, such as BA.2 and BA.5. There seems to be a direct correlation between the RBD changes and the faster it spreads both within the body and the population. This is where BQ.1 and BQ.1.1 differ; variants, such as BQ.1, with five key RBD changes (relative to BA.2) seem to be growing in number at a slower rate than variants with six changes. A descendant of BQ.1 called BQ.1.1 has six such changes, and is rising rapidly across Europe, North America and other places.

Double Immunity?

Another variant of COVID-19, XBB, is predicted to “gain an edge” against BQ.1.1 because it has seven changes in its RBD, allowing it to grow at an even faster rate. Although there is currently no data to back up the theory that double immunity could be at play, researcher Cao and his team have a feeling that if you’re infected with BQ.1, you might have some protection against XBB.

How to Stay Safe

Although there is never a 100% guarantee that you won’t catch BQ.1, BQ.1.1, or XBB, there are preventative measures you can take to decrease your chances. As we have been advised since the start of COVID, one should continue to stay sanitary, wear a mask if in a susceptible/crowded place, and be updated on new vaccines. Winter is coming, and it is time to fortify and protect yourself against what lurks beyond your body’s walls.