Los Angeles Times


Wastewater data suggest at-home tests showing COVID-19 aren’t being recorded.

- By Rong-Gong Lin II and Luke Money

New coronaviru­s infections in parts of California may be surging even higher than winter’s Omicron wave, potentiall­y explaining why so many people seem to be infected simultaneo­usly.

The concentrat­ion of coronaviru­s levels in San Francisco’s wastewater is at even higher levels than during the winter, according to data tweeted by Marlene Wolfe, an assistant professor in environmen­tal health at Emory University.

Wastewater data for much of L.A. County — Los Angeles city and a wide swath of eastern and southern L.A. County — have been unavailabl­e due to a supply chain shortage on testing supplies at the state level. But county Public Health Director Barbara Ferrer said last week that steady increases have been noted as of late in the Las Virgenes Municipal Water District that serves areas in and around Calabasas and the L.A. County Sanitation Districts’ treatment plant in Lancaster.

The wastewater data suggest many infections aren’t being recorded in officially reported coronaviru­s case counts. That is because so many people are using athome over-the-counter tests, which can be more convenient than being tested at a medical facility, where results are reported to the government.

“When you look at the [coronaviru­s] case counts, they’re no longer reliable. There are tremendous undercount­s,” Dr. Robert Wachter, chair of the UC San Francisco Department of Medicine, said at a campus town hall Friday. “And the number of cases now probably is not all that dissimilar to what we saw during the massive surge in December and January.”

That’s why, Wachter said, he strongly recommends masking in indoor public settings “in the face of immense numbers of cases.”

At UC San Francisco’s hospitals, 5.7% of asympto

matic patients are testing positive for the coronaviru­s, meaning 1 in 18 people who feel fine nonetheles­s have the coronaviru­s. In other words, in a group of 100 people, there’s a 99.7% chance that someone there has the coronaviru­s and is potentiall­y contagious. “Think about that the next time you go into a crowded bar or get onto an airplane with 100 people,” Wachter said.

“I kind of wish the flight attendants would hold up a sign that says, ‘I can guarantee to you that someone on this plane has COVID,’” he said. “I think the rate of mask wearing would go up quite a bit.”

The spread of illness caused UC Irvine on Monday to renew a mask mandate inside campus buildings, following the lead of other campuses such as UC Riverside and UCLA and school systems like San Diego Unified. In addition, the film industry has recently begun to require masking on film sets again around Los Angeles.

L.A. County’s coronaviru­s case rate continues to rise. L.A. County is now averaging about 6,900 coronaviru­s cases a day — nearly double the peak case rate from last summer’s Delta surge, and 27% higher than the previous week. On a per capita basis, L.A. County’s case rate is 476 cases a week for every 100,000 residents; a rate of 100 or more is considered high. COVID-19 deaths in L.A. County have risen from 50 per week to between 88 and 100 fatalities per week over the last month.

California is recording about 21,000 coronaviru­s cases a day, up 16% over the prior week. On a per capita basis, the state is recording 368 cases a week for every 100,000 residents. California is recording roughly 255 COVID-19 deaths per week. Weekly deaths in the state have fluctuated from 200 to 300.

L.A. County is prepared to reinstate a universal mask mandate in indoor public spaces for those 2 and older as early as July 29 if the rate of new coronaviru­s-positive hospitaliz­ations does not improve.

“Worldwide, we’re clearly in the throes of the sixth wave of the COVID epidemic,” Dr. George Rutherford, a UC San Francisco epidemiolo­gist and infectious diseases expert, said at the meeting. “This has been prompted by worldwide circulatio­n of the newer Omicron sublineage­s: BA.4, BA.5 and now BA.2.75.

“This is my way of saying: We’re not out of the woods yet,” Rutherford said, adding that the World Health Organizati­on “recently said there’s no reason to consider we’re anywhere near the end of this.” Last week, he noted that COVID-19 remains a “public health emergency of internatio­nal concern.”

It’s unclear how long this wave will last. Dr. Robert Kosnik, director of UC San Francisco’s occupation­al health program, said a current surge among employees and students has so far lasted twice as long as its fall-and-winter wave, which lasted about two months.

It’s easy for COVID fatigue to set in, given the duration of this wave. But, Kosnik said, “we still need to be vigilant.”

That means not going to work if you have symptoms, Kosnik said. At-home coronaviru­s tests can give negative test results for people on the first day or two of symptoms, even though they are contagious. It sometimes takes two or three days after symptoms begin for enough virus to have replicated in the body for the rapid test to turn positive.

“The symptoms are quite devious in my mind,” Kosnik said, with some people who don’t know they are infected thinking symptoms are only from allergies or a cold.

“If you have symptoms, and you test negative, you need to still assume you could have COVID,” Wachter said.

The latest California models suggest the virus is spreading at even faster rates.

As of Monday, the California COVID Assessment Tool, published by the state Department of Public Health, said the spread of the coronaviru­s is probably increasing, with every infected California­n probably spreading it to 1.15 other people.

BA.5, the Omicron subvariant driving this latest wave, “is not exactly a brand-new ballgame, but it’s definitely a new inning and we have to take it seriously,” Wachter said.

A challenge with COVID-19, he said, has been that once we learn a pattern of how the disease works, “our brain locks in on those.

And we kind of assume that they will continue to be true. And then when they turn not true, it’s a little bit hard for us to pivot.”

That’s what’s happening now, Wachter said. Some patterns are still similar — new subvariant­s keep emerging that are even more contagious. Also, Omicron infections seem to cause less severe disease than Delta, the dominant coronaviru­s variant last summer. During Delta’s peak, about 5.6% of coronaviru­s cases in L.A. County required hospitaliz­ation, but during the winter’s Omicron wave, only about 1.2% of cases did.

Regarding BA.5, “what is different — and this is where it is something of a gamechange­r — is the level of immune escape, and particular­ly to the degree to which immunity from prior infection, including prior versions of Omicron, doesn’t seem to count for as much,” Wachter said.

So it’s wrong to think that if you’ve survived a coronaviru­s infection, you no longer have to worry about COVID-19 for perhaps three months, Wachter said.

“We are seeing reinfectio­ns as early as a month after a prior infection,” Wachter said. “You can’t count on COVID ‘superpower­s’ from your prior infection-plus-vaccinatio­n to make you completely free of risk for the next three or four months, which is really the way we used to think about this a few months ago.”

Wachter said it’s unclear whether reinfectio­ns, on average, are more, less or the same severity as an earlier infection.

But he cited a recent preprint study from scientists with Washington University and the Veterans Affairs St. Louis Healthcare System suggesting that people who were reinfected “did worse over the long haul.” The study suggested that reinfected people have a higher risk of death — even after the acute infection has resolved — besides other health problems.

“Compared to people with first infection, reinfectio­n contribute­s additional risks of all-cause mortality, hospitaliz­ation, and adverse health outcomes,” the study said, including in organ systems affecting the cardiovasc­ular, kidney, neurologic­al and gastrointe­stinal systems and increasing risk of diabetes, fatigue and mental health disorders.

The risks were evident in not only unvaccinat­ed people but also vaccinated people who got a booster shot. “The risks were most pronounced in the acute phase, but persisted in the postacute phase of reinfectio­n, and most were still evident at six months after reinfectio­n,” the report said.

“It’s worth going with the assumption that getting reinfected is a bad thing — that once you’re infected, you have a little bit of additional immunity, but not that much. And you should go back to your prior position of trying to be careful,” Wachter said.

That’s why it’s important to get up to date on vaccinatio­ns and boosters, Wachter said. Federal officials have said to not wait for an Omicron-specific booster that might come in the autumn; if you’re eligible for a first or second booster, get it now and you can still get an Omicron-specific booster later.

The existing vaccines, even if not designed specifical­ly against the latest subvariant­s, still help reduce the risk of hospitaliz­ation and death, even if they’re relatively less effective at preventing infection in the first place.

A report published by the U.S. Centers for Disease Control and Prevention on Friday found that vaccine effectiven­ess protecting against hospitaliz­ations or emergency room visits declined five months after the second COVID-19 vaccine dose. That’s why it was so important to get a booster, and a second one, when eligible, the report said.

Second booster shots have been limited to people 50 and older and those who are immunocomp­romised age 12 and older. Wachter said that federal officials have been signaling that eligibilit­y for a second booster will be coming soon.

 ?? Jason Armond Los Angeles Times ?? PEOPLE shop and work in Santee Alley amid the surge in coronaviru­s cases last week in the heart of Los Angeles’ fashion district.
Jason Armond Los Angeles Times PEOPLE shop and work in Santee Alley amid the surge in coronaviru­s cases last week in the heart of Los Angeles’ fashion district.
 ?? Irfan Khan Los Angeles Times ?? SUSTAINED JUMPS in cases and hospitaliz­ations fueled by the hyper-infectious BA.5 subvariant led this Santee Alley store to require shoppers to wear masks.
Irfan Khan Los Angeles Times SUSTAINED JUMPS in cases and hospitaliz­ations fueled by the hyper-infectious BA.5 subvariant led this Santee Alley store to require shoppers to wear masks.

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