New, highly transmissible COVID-19 variant BA.5 dominating cases
BALTIMORE — If you’ve recently been infected with COVID-19 or know someone infected, and you probably do, you can probably blame BA.5, one of five subvariants of omicron and possibly the most transmissible yet.
It’s now the dominant strain in Maryland and nationally and, along with a close relative, BA.4, accounts for 70% of U.S. cases. And it’s not just contagious, it’s also adept at evading people’s immune defenses, making it a particular threat.
“What that means is there is a smaller hill for the virus to get over,” said Andrew Pekosz, a professor of immunology at Johns Hopkins Bloomberg School of Public Health who has been studying the coronavirus. “We’re going to see a lot of infections and reinfections.”
That would be infections in people who are vaccinated and boosted, as well as people who were infected during the last wave.
It’s another frustrating turn in the long coronavirus pandemic, which experts say again calls for vigilance: wearing good-fitting, quality masks in higher-risk situations, distancing, seeking well-ventilated indoor spaces and obtaining every vaccine dose for which people are eligible.
The state and nation are seeing cases creep up, with 1,873 new infections reported Friday, up from a few hundred a day in mid-March, according to the Maryland Department of Health. The ultimate tally is unknown but surely far higher because so many people are testing at home and not reporting the results.
The percentage of people who officially test positive in a state or commercial lab, however, is also ticking up. It was 9.5% on Friday, nearly double the standard threshold of 5% that indicates infections are widespread in the community. The CDC considers spread in most of Maryland to be low or medium, with only Howard County listed as high, designations largely tied to the level of COVID-19 hospitalizations.
Chase Cook, a spokesman for the state health department, said officials are monitoring the pandemic and will provide guidance as necessary.
“Maryland is one of the most vaccinated states in the country,” he said. “We encourage every eligible Marylander to get vaccinated and boosted as soon as possible — safe and effective vaccines are available at hundreds of sites at covidvax.maryland.gov.”
It’s not clear yet how big an impact BA.5 will have on hospitalizations and deaths, though there currently are 536 people in hospital beds in Maryland. That’s more than five times the recent low in mid-April of just over 100, but far from the pandemic high in January that exceeded 3,460.
That number has been rising, though the data don’t show how many are “for or with” COVID-19, said Kathleen Neuzil, director of the University of Maryland School of Medicine’s Center for Vaccine Development and Global Health. That is, how many people are in a hospital bed because they have COVID-19 or just tested positive after seeking medical care for something else.
Neuzil said the rise of BA.4 and BA.5 isn’t surprising because they’ve caused a lot of infections in Europe and South Africa, and the United States has been following those trends. She hesitated to predict exactly how the cases would trend here or when they would peak, given the virus’ unpredictability and other variables, such as how much Americans take precautions absent any mandates.
A third of the country remains unvaccinated and booster uptake so far has been low. The rate of vaccinations for small children, which were recently authorized, also is low, prompting the American Medical Association, American Academy of Pediatrics and American Academy of Family Physicians to issue an open letter to parents urging them to immunize their kids.
“COVID-19 is unpredictable, and we do not know which children will suffer severe, long-term or debilitating symptoms,” says the letter. “According to the Centers for Disease Control and Prevention, COVID-19 was among the leading causes of death among children the past two years. Even otherwise healthy children with no underlying medical conditions can experience both short- and long-term health complications from COVID-19 that can affect their mental and physical health and quality of life.”
Neuzil also urged people to be vaccinated now ahead of whatever is to come in the few months. The Pfizer/BioNTech and Moderna vaccines for adults require two doses and the Pfizer vaccine for young children requires three doses over time.
As for the rest of summer, she said all the outdoor activity could mean there won’t be a hefty surge in cases. That’s more or less what the models for the state and country show from the University of Washington’s Institute for Health Metrics and Evaluation, with cases even dipping a bit and then rising by fall.
There is some good, or less-bad, news, she and Pekosz say. The number becoming seriously ill from BA.5 is likely to be held down by the sheer number of people who have already been vaccinated and infected. The body remembers how to fight off the worst of the virus, even if it can’t stop the infection.
Also, there are antiviral medications that are effective, if taken early, in lessening the blow from COVID-19, Pekosz said. Maryland has expanded its “test to treat” program, allowing people to get tested at state sites and pharmacies and pick up the medications at the same time.
Neuzil said this fall there could be another tool, a vaccine specifically covering including BA.4 and BA.5. The U.S. Food and Drug Administration has recommended the vaccine specifically protect against the omicron subvariants. If the data shows that it could help, and advisers and regulators sign off, it could be manufactured and available as students return to school and people begin to spend more time indoors.
Neuzil’s center has been involved with testing many of the COVID-19 vaccines in use, and noted that altering the mRNA vaccines from Pfizer and Moderna to include new strains wouldn’t have to go through the same human trials for authorization.
But she and Pekosz both advise not to wait for the newer version of the vaccine. People should go now to be vaccinated and boosted — those over age 50 or immunocompromised qualify for a second booster. People will likely qualify for another shot by the time one is available.
Pekosz said the virus keeps evolving, so keeping up defenses is paramount.
“This virus is really exploring a lot of space,” he said. “It’s difficult to predict how far this virus can go with all the new properties it brought with it from when it first emerged.”
Plus, the fall is likely to see the return of another virus, influenza. Largely absent for two seasons because people were heavily masking and taking other precautions, the flu has raged across Australia, a bellwether continent considered by U.S. scientists planning for our next flu season.
Pekosz, a longtime flu researcher, said there is time to update the annual flu vaccine to capture the circulating strains.
But he and Neuzil added that the fall could be brutal, as there are still lingering cases of flu and other respiratory viruses being reported from the past season, in addition to COVID-19. People also have lost much of their natural immunity over time.
“The last two years we worried about flu and didn’t see a lot of it,” Neuzil said.
“Be prepared this winter,” she said. “Get vaccinated against influenza.”