As officials in California and beyond try to gauge how severe a fall and winter coronavirus wave could be, a key factor is the growth of several new subvariants now emerging.
It’s still too early to tell if any of the newer variants will gain traction the way Omicron and Delta have. None have been documented in significant numbers in California or the nation. However, experts say another super-spreading sub-variant — combined with more people staying indoors during cold weather — could introduce new challenges.
“As we get into the coming late fall and winter… another variant is likely to emerge,” said Dr. Anthony Fauci, Biden’s senior medical adviser for the pandemic, during a recent virtual presentation by the Center for Strategic and International Studies.
An increase in COVID-19 cases is generally expected this fall and winter. New York has already been on an uptrend since hitting a seasonal low in early September.
California is in a doldrums for now as cases and hospitalizations have been declining since mid-summer. But in Los Angeles County, weekly deaths remain high, well above spring lows, likely reflecting a case rate that, while improving, is still significant.
“We are all prepared for an increase in cases this fall. I think we want that to be minimal, and we think if more people can go ahead and protect themselves with the new bivalent boosters, that’s going to really help everyone dampen the possibility of a very big spike,” LA County said Health Director Barbara Ferrer.
However, given the unpredictability of the coronavirus, officials cannot rule out the possibility of a severe surge.
“It would be foolish not to be prepared for uncertainty because we’ve just seen so much uncertainty,” Ferrer said. “It’s a coronavirus. It mutates a lot. We cannot change this reality. [But] we are very optimistic. We have great tools.”
After the distribution of COVID-19 vaccines, the earlier flare-ups of the pandemic coincided with the emergence of new variants or subvariants that were more easily transmissible and circumvented protection from vaccines or previous infections.
Such constant mutations make the coronavirus a moving target. While officials are broadly confident that California and the US are relatively well positioned heading into the colder months – thanks to immediate supplies of vaccines, therapeutics and the rollout of updated booster shots – they continue to keep a vigilant eye on the horizon.
Most problematic variants were denoted by letters from the Latin alphabet: epsilon, alpha, delta, and omicron.
Omicron has dominated the globe since last fall, and today’s viral landscape is now characterized by several subvariants of this strain. They are not denoted by Latin letters, but by alphanumeric identifiers, which have become more complex over time.
Among them is BA.2.75.2, which Fauci identified as “one that looks suspicious — that it might develop into one.” [troublesome] Variant.”
BA.2.75.2 has not been widely distributed in the US, and the Centers for Disease Control and Prevention does not count it separately from the less concerning but similarly named BA.2.75.
“The one we’ve been most worried about lately is BA.2.75.2,” said Dr. Benjamin Pinsky, director of the Clinical Virology Laboratory at Stanford University.
In Stanford’s lab, scientists have only identified one case of this subvariant, he said.
The concern with BA.2.75.2 is that our collective antibodies – whether derived from a previous vaccination or case – may be less able to recognize this new subvariant and fight off infection.
In particular, a preprint study published in mid-September by scientists from Europe and Africa found that samples from random blood donors in Sweden were much less likely to detect BA.2.75.2 compared to previous subvariants.
The study also suggested that the anti-COVID drug Evusheld was less effective against BA.2.75.2. Evusheld is a monoclonal antibody given to people with weakened immune systems to prevent coronavirus infection. Another monoclonal antibody, bebtelovimab, was still able to detect BA.2.75.2.
“Taken together, these data indicate a profound leakage of antibodies by the emerging Omicron sublineage BA.2.75.2, suggesting that it is effectively evading the current [antibody] Immunity in the population,” says the report.
dr Eric Topol, director of the Scripps Research Translational Institute in La Jolla, said two of the more worrying subvariants are BA.2.75.2 and BQ.1.1.
“They have already established themselves as the most extreme immune escape observed to date,” he said. And being more skilled than BA.5 – the currently dominant Omicron subvariant – “is not a good thing”.
Immune Escape means “our immune system doesn’t see it very well because it has many different mutations. So there’s basically a workaround,” Topol said. “We’ve never seen this before, and that’s why it has enough mutations to be able to enter us despite our immune response, because our immune response — it has a blind spot.”
Another subvariant, BA.2.3.20, could potentially be worse because it has many mutations, although its level of immune escape has not been characterized, Topol said. And a fourth mutation worth watching is known as XBB.
What all of these newer subvariants have in common is that “they have a growth advantage,” Topol said.
dr UC San Francisco infectious disease expert Peter Chin-Hong observes another subvariant, BF.7, also known as BA.18.104.22.168, which could contribute to a significant proportion of cases in Belgium and other European countries.
“It seems BF.7 has some legs right now,” Chin-Hong said. “The fact that this grandchild [of the original Omicron strain] increasing means it can probably evade immunity because many people have already become infected in Europe” with BA.5.
None of these subvarieties circulate at high levels in the US, CDC data shows. And there is hope that updated bivalent boosters – designed specifically for BA.5 and another Omicron subvariant, BA.4 – will also offer additional protection against the offspring of these subvariants such as BF.7 and BA.4.6.
However, what is worrying about other strains with high levels of immune escape, including BA.2.75.2, is that they could start a new surge and potentially reinfect people who have even recently recovered – something that will happen this summer happened when BA.5 was superseded BA.2.12.1.
“What we learned during Omicron is that even vaccinated people can die if they are not vaccinated,” Chin-Hong said. “And it affects the older folks disproportionately.”
When a sub-variant emerges that is “truly immune-preventable, it means more people are getting infected because our ‘force field’ is being broken in general as a community. And the more people get infected, the easier it is for the elderly to become infected, and therefore, if not amplified, they could become seriously ill.
“I think hospitals should be on guard,” he added.
People at lower risk of severe COVID-19 — people with some immunity from vaccination or previous infection — are less likely to develop serious illness or death. Even if they do become infected, other parts of the immune system that take longer to ramp up and still function regardless of the subvariant are expected to respond and reduce the risk of serious illness.
But for those at higher risk, their immune systems need more frequent booster shots to protect them better. Your immune system “is sluggish. They definitely need more reminders,” Chin-Hong said.
A grim scenario would be combining the worst traits of new subvariants to form yet another new version.
“One of the questions people ask is recombination: How can you mix and match the best qualities of one with the other. And at some point you happen to get something that has, for example, the BA.2.75.2 immune evasion and the BF.7 portability,” Chin-Hong said.
Among those at higher risk, COVID-19 still causes hospitalizations and deaths, particularly among people who are not up to date on vaccinations. About 350 to 500 Americans have been dying from COVID-19 every day since August, which would add up to four to five times the annual flu death toll in an average year.
“It’s a level of suffering and death that we don’t accept as ‘living with COVID,'” said Dr. Ashish Jha, the White House COVID-19 response coordinator, on Tuesday at a forum hosted by the Center for Strategic and International Studies.
In the San Francisco Bay Area, which has never been harder hit by the pandemic than LA County, some experts believe the era of local mask mandates is over.
But in LA County, health officials say — while this winter might be optimistic — they need to be prepared for a scenario where booster shots are less helpful than expected because of new subvariants.
As a result, the LA County Department of Health has not ruled out reinstating mandatory mask mandates if hospital conditions become critical.
If “we’re in a situation where the healthcare system is under threat and we’re surrounded by people who are getting very sick … I think people are going to go ahead and comply,” Ferrer said. “These are sensible public health precautions.”
She suspected that health officials elsewhere in California would reevaluate safety measures if hospitals were hit again. LA County health officials were the first to reintroduce a mask mandate in response to the increasing Delta variant last summer. Other local governments and states adopted this approach over the following weeks and months as more threats emerged, including Omicron.
“We are also realistic enough to know that there is always a place for rules to ensure that the collective good can actually be realized,” Ferrer said.
https://www.latimes.com/california/story/2022-10-01/new-coronavirus-subvariants-a-worry-for-winter-covid-wave New coronavirus subvariants a worry for winter COVID wave