The coronavirus continues to mutate rapidly. In the latter half of August, the BA.5 subvariant made up more than 85 percent of COVID-19 infections in the U.S. Now, just three months later, BA.5 accounts for just under one-quarter of cases while BQ.1 and BQ.1.1 are responsible for nearly half of infections in the country, according to latest data from the Centers for Disease Control and Prevention (CDC).
Because the BQ variants are new, more research is needed to determine exactly how harmful they may be. Evidence so far suggests they spread easily but cause milder illness that the original and delta strains of the virus.
As the BQ variants have grown, so have the latest COVID-19 numbers. Analysis from The New York Times?shows that the daily average of cases has increased by 4 percent over two weeks leading up to November 21. The number of people in intensive care units has risen by 6 percent over the same time period.
“Omicron continues to mutate and the newest subvariants, BQ.1 and BQ.1.1, are very transmissible and our current vaccines and monoclonal antibody treatments do not work quite as well against them,” said William Schaffner, MD, an infectious disease specialist and professor of preventive medicine and health policy at the Vanderbilt University School of Medicine in Nashville, Tennessee. “Nevertheless, the current vaccines continue to provide substantial protection against severe disease, hospitalization, and death.”
Last week, Pfizer?released preliminary results from an analysis showing that its latest omicron BA.4-BA.5-adapted bivalent COVID-19 vaccine produced a strong immune response against newer omicron sublineages, including BQ.1.1, BA.4.6, BA.2.75.2, and XBB.1. Neutralizing antibodies against these sublineages increased 4.8- to 11.1-fold from prebooster levels one month following a 30-microgram dose of the new bivalent booster.
Moderna?last week also released early data indicating that its updated booster produced neutralizing activity against BQ.1.1, “confirming that updated vaccines have the potential to offer protection as the virus continues to evolve rapidly to escape our immunity.”
As more people gather indoors for the holidays, Dr. Schaffner stresses that the new boosters provide vital protection. “This coming holiday season will provide many occasions for these highly contagious viruses to cause disease, so the booster is something that we all should be thankful for and getting it is the best present you can give yourself, your family, and your friends,” he said.
While the new omicron-targeting vaccine is available to those ages 5 and older, the?CDC?says only 11.3 percent of the population has gotten the shot.
In addition to recommending getting boosted, health authorities are urging the public to take extra precautions to avoid the spread of COVID-19 and other respiratory viruses.
“With respiratory illnesses such as RSV, the flu, and COVID-19 leading to increased illness and hospitalizations, I strongly recommend using all available strategies to stay healthy and safe,” said Sameer Vohra, MD, director of the Illinois Department of Pubic Health, in a statement. “These strategies include COVID-19 testing, especially if visiting someone at risk for severe disease, enhanced ventilation, good hand hygiene, staying home if sick, and getting up to date with both the COVID-19 bivalent booster and the flu shot.”
Taking such measures especially helps the most vulnerable, such as those who are immunocompromised and more susceptible to severe illness from the BQ subvariants. The?National Institutes of Health released a statement last week saying that the treatment Evusheld (tixagevimab and cilgavimab), which has successfully protected immunocompromised individuals from previous strains of the coronavirus, is likely to be ineffective against BQ.1 and BQ.1.1.