California tops 12 million coronavirus cases as XBB.1.5 becomes dominant

Luke Money

LOS ANGELES — The total number of coronavirus cases reported in California has topped 12 million.

That milestone — reached last week, according to data compiled by The Times — comes as California is seeing increased circulation of the omicron subvariant XBB.1.5, which has been described as perhaps the most infectious strain of the coronavirus.

But in many respects, the pandemic picture remains relatively rosy, with newly reported infections declining and stabilizing in recent weeks. Hospitalizations have also ticked down to levels not seen since mid-November, indicating less strain on the health care system.

“We do have more tools now than we’ve had at any point during the pandemic,” Los Angeles County Public Health Director Barbara Ferrer told reporters. “While new strains always have the potential to drive surges in cases, to date, we’ve not seen a major increase in cases associated with XBB.1.5.”

The statewide tally — just under 12.02 million cases as of Friday, according to The Times’ tracker — is undoubtedly an undercount, because of both limited access to testing in the pandemic’s early days and the fact that many people now self-diagnose using at-home tests.

Even so, the figure constitutes a population larger than that of all but six states.

Modeling from the California Department of Public Health estimates that the spread of COVID-19 is probably decreasing statewide and has been for more than a month.

Still, the coronavirus has thrown its share of curveballs during the last three years. The latest is XBB.1.5, a member of the sprawling family of omicron subvariants that have been dominant in the U.S. for months.

That strain accounted for an estimated 74.7% of cases over the last week, according to the U.S. Centers for Disease Control and Prevention.

Its rise has been slower in California, Nevada, Arizona, Hawaii and the Pacific islands. But even in that Western region, XBB.1.5 accounts for an estimated 56.9% of new cases.

Despite its infectiousness, XBB.1.5 has not spawned a major spike in hospitalizations — sparking optimism that it may not be the beastly “Kraken” some had feared.

“Outside the Northeast region during XBB.1.5’s rise, there was no surge in hospitalizations,” Dr. Eric Topol, director of the Scripps Research Translational Institute in La Jolla, tweeted Friday.

In California, the number of coronavirus-positive patients hospitalized Thursday was 2,485. That’s down markedly from this winter’s high of more than 4,600.

This is the first year that California did not experience a devastating surge coinciding with winter, a development many officials attribute to the widespread administration of vaccines.

“Real-world evidence continues to show that the vaccine prevents severe illness, hospitalization and death,” the California Department of Public Health said in a statement Thursday. “Public health officials urge Californians to get vaccinated and boosted as soon as they are eligible.”

According to the department, unvaccinated Californians were 2.4 times more likely to contract COVID-19 in December than those who had received at least their primary vaccine series. The unvaccinated were also 2.6 times more likely to be hospitalized and three times more likely to die from the disease.

The comparatively mild winter resurrected discussion of the once-hot topic of herd immunity — the point at which so many people are immune to a virus that it has difficulty finding new hosts to infect. While thousands of new cases are being reported each day in California, many individuals enjoy some protection through vaccination, prior infection or a combination of the two, experts say.

“We don’t really talk about herd immunity anymore. What we’ve learned about this virus is that it continues to change and mutate, and it’s sort of a dance between the immunity in the population and what the virus is doing — and it’s a continual change. It’s dynamic,” Dr. Sara Cody, Santa Clara County’s public health director and health officer, said during a news conference last week.

The way to think about it is “you’re more protected if you’re vaccinated,” she said. “You’re less protected if you’ve never been vaccinated or it’s been a long time since you’ve been vaccinated, and that’s when you need to add some extra layers.”

Aside from vaccination, Californians should mask up in indoor public settings, particularly among crowds, health officials say. Other familiar recommendations include practicing good hand hygiene, covering your mouth and nose when you cough or sneeze, staying home when you’re sick, testing if you suspect you’ve been exposed to the coronavirus and promptly seeking treatment if infected.