It’s the most infectious strain yet, coming even as many people have written off the pandemic.
BA.5, now the dominant coronavirus subvariant in New Jersey and the US, has shown resistance to COVID-19 vaccines, making experts nervous. Worse, prior immunity doesn’t seem to be the shield it once was as protection from recent infection appears to offer reduced or even no armor against the strain.
“It seems to be by far the most transmissible variant that we have seen,” said Stephanie Silvera, an infectious disease expert and professor at Montclair State University.
New infections in New Jersey are rising. Hospitalizations are at four-month highs. And fall and winter — when pandemic surges have become commonplace — are just around the corner.
Hospitalizations reached 1,013 as of Tuesday night with 39 patients on ventilators, according to the state Department of Health. It’s the first time New Jersey has topped 1,000 hospital admissions since Feb. 22. The state’s seven-day average for confirmed positive tests is 2,623, a more than 900% increase from the same date a year ago.
“A lot more people are susceptible to this strain than they have been in the past,” said Dr. David Cennimo, an infectious disease expert at Rutgers New Jersey Medical School.
He called it a “perfect storm.” BA.5 comes as people are losing immunity and stopped taking precautionary measures like wearing masks in public places.
“It feels like this is hitting at this point where everybody kind of decided to stop taking precautions,” he said.
Infections still tend to be mild for most people, he noted. He suspects the vaccines are still offering some protection.
“So I don’t think it’s horrible just yet,” Cennimo said. “But it’s definitely something to be watched and to be concerned about. And I think we probably should be a little bit more careful right now.”
He’s worried the situation could dramatically deteriorate in the fall and winter with people heading back indoors and as cold and flu season returns.
Whether people will change their patterns is unclear. Some wear masks in stores, but most don’t. Some are getting booster shots, but some aren’t. People are unsure if they should get a booster now or if they should wait until later in the year, when a new and improved vaccine geared to protect against omicron subvariants may be released.
But Silvera is concerned that vaccine version won’t be ready in time — and people may not get it.
The tricky thing with BA.5 — a mutation of the already contagious omicron variant — is that it’s rendering the existing vaccines and boosters less effective. That has long been one of the experts’ biggest concerns. It is also causing people who once had immunity to become reinfected.
“The rate of reinfection does seem to be up and the time of that protective bubble, which we used to think was about 90 days, seems to be diminishing with this BA.5 because it is so highly transmissible,” Silvera said, “and because it does evade immune protection much more efficiently than previous sublineages or other variants that have been out there. We’re starting to see people who’ve had omicron in January or even April who are now being reinfected.”
Dr. Bob Wachter, the chair of the department of medicine at the University of California, San Francisco, agrees.
“Not only is it more infectious, but your prior immunity doesn’t count for as much as it used to,” he recently told NPR. “And that means that the old saw that, ‘I just had COVID a month ago, and so I have COVID immunity superpowers, I’m not going to get it again’ — that no longer holds.”
Though BA.5 is proving to be an effective spreader, “whether or not it is more likely to cause hospitalization I don’t think has been fully determined,” Silvera said.
She wonders how many people have surpassed the six-month window since their last vaccine or booster shot. It could amount to millions of New Jersey residents.
And maybe most chilling of all, BA.5 seems to be impacting the immune system, making people more susceptible not only to COVID-19 reinfection but to other viral infections as well.
“By being reinfected, you’re actually more likely to be infected again,” Silvera said, “maybe a third or fourth time because of the wearing away at our immune system by COVID.”
Some preliminary data, she noted, also showed people who had COVID-19 recently had reduced white blood cell counts.
“That may mean that they’re less likely to fight off not just COVID, but they’re getting secondary infections, so they may be more susceptible to other illnesses,” Silvera said.
“There has been some impact even on people who’ve had milder illness,” she added.
More bad news?
The subvariant is continuously mutating, making it even harder for the immune system to fight back.
“There’s been enough mutations in BA.5 that the immune system doesn’t recognize as well or as quickly and the antibodies don’t stick as well,” Cennimo said.
And another new strain is already circulating. BA.2.75 — which emerged recently and has been found in India and 10 other nations, including the US — appears to spread rapidly and evade protection from vaccines and previous infection.
Cennimo predicts there will be a booster recommendation come the fall — when the tweaked vaccine specific for omicron subvariants is expected. He’s bracing for what could happen at that point, as other viruses circulate. How many people will get a booster? How many people will get a flu shot?
“I’m going to assume that behaviors aren’t going to change,” Cennimo said. “So we’re going to be watching those numbers, co-mingled with numbers of flu infection, adenovirus, rhinovirus, everything else.”
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Spencer Kent may be reached at email@example.com.