In a milestone, California says those with COVID-19 can leave home sooner — but there's a catch

Pasadena, CA - October 12: Tracy Gage, LVN, prepares a syringe at a flu and COVID vaccination clinic Kaiser Permanente Pasadena on Thursday, Oct. 12, 2023, in Pasadena, CA. (Francine Orr / Los Angeles Times)
Tracy Gage prepares a syringe at a flu and COVID vaccination clinic at Kaiser Permanente Pasadena. (Francine Orr / Los Angeles Times)
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California's relaxed COVID isolation guidance marks a milestone in public health messaging about the pandemic: Even newly infected people no longer need to isolate if they have no symptoms, or they can leave home sooner if the illness starts improving quickly.

California's stance is even looser than that of the U.S. Centers for Disease Control and Prevention, which advises isolating for at least five days after the onset of symptoms or, if asymptomatic, after the first positive test.

The changing recommendations, which have gained attention as the winter COVID wave shows signs of cresting in California, underscores the evolving nature of the coronavirus threat.

But they come with one vital warning. Health officials say infected people who venture out need to mask up. If they don't, they could easily transmit the coronavirus to others.

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Dr. Peter Chin-Hong, a UC San Francisco infectious disease expert, said he thinks California's new isolation guidance makes sense, but "the only sort-of worry I have is that people are not going to do the mask part, but they're just going to focus on the fact that you don't have to stay home for five days.

"People focus on what has changed, but they don't focus on what hasn't changed," Chin-Hong said. "Masks should really be part of normal life, like if you're sick or you have symptoms, put the mask on — regardless of what you have; it could be COVID, a cold, RSV, influenza."

The guidance says masks should be well-fitting and have optimal filtration; ideally, an N95, KN95 or KF94 model.

Read more: California relaxes COVID isolation guidance. What you need to know

It's also important that those who do have symptoms test themselves.

"Some days, it might be an allergy, but some days it might be that you did pick up COVID," said Dr. Daisy Dodd, an infectious diseases specialist with Kaiser Permanente Orange County.

California's new guidance says that people who have COVID-19 symptoms need to isolate and test themselves. An early negative test may not mean the person doesn't have COVID; the CDC suggests testing again two and four days after the onset of symptoms.

Those who test positive but remain asymptomatic need not isolate but must wear a high-quality mask when around others for 10 days after the first positive test.

Those who do develop symptoms — such as a cough, sore throat, runny nose or body aches — can end their isolation period once their symptoms are mild and improving, provided they haven’t had a fever for 24 hours without using medication. Still, they need to wear a mask for 10 days after the onset of symptoms.

Whether symptomatic or not, those with COVID can stop wearing a mask before 10 days if they test negative on two consecutive rapid tests, taken at least one day apart.

Los Angeles County also recommends waiting for a negative rapid test before leaving isolation within the 10 days following the first symptoms. A negative rapid test result is not needed on Day 11 or after.

Some experts have criticized California's looser isolation guidance. On social media, Michael Mina, chief science officer for eMed and an epidemiologist formerly with the Harvard T.H. Chan School of Public Health, wrote that it "essentially encourages" infectious people to "return to work/school & infect others."

"It is outrageous," Mina wrote. "They advise: if no fever, but blazing positive rapid test, no worries, go back to work/school!"

Mina suggested that a better approach would be to ask people to isolate for a period "no more and no less" than they are a risk to others — a decision that can be made when the person tests negative on a rapid test as they recover. Rapid test results are "real personalized empirical data correlated with being infectious," Mina wrote.

Others note that the new state guidance hasn't resulted in a severe public backlash. And many residents haven't been following official guidance for a long time anyway, thinking it doesn't make sense to stay home if they feel fine.

"That's part of the thing: People are doing this anyway, so you might as well give them best practices," Chin-Hong said, stressing mask use for those infected.

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The guidance, issued Jan. 9, has been echoed by local officials in recent weeks amid a significant wave of coronavirus infections. State and national data posted by the CDC suggest that levels of the virus in sewage are at the highest point since the first Omicron wave two winters ago.

The wave of illness has been noticeable in causing more workers to call in sick. Many describe miserable illnesses with intensely sore throats that feel like they're studded with shards of glass, coughing fits that leave them winded and body aches that make them feel as if they've been hit by a truck.

California clinicians this winter have noted patients who tested positive for COVID-19 and flu at the same time.

Notably, there are fewer incidents of severe acute COVID-19 illness than there were in the early years of the pandemic. New COVID-19 hospitalizations are at the lowest points for a winter season since the pandemic began. It's likely that vaccinations, natural immunity from past infections and the development of medications such as Paxlovid have made the disease much less risky. However, any bout with the illness presents the risk of developing into long COVID.

Lower levels of severe illness were a big part of California's rationale for loosening the isolation guidance. Prior guidelines were set when Californians "had little immunity" and there were a "large number of hospitalizations and deaths that overwhelmed our healthcare systems," officials wrote. "We are now at a different point in time with reduced impacts from COVID-19 compared to prior years."

Read more: With COVID on the rise, your at-home test may be taking longer to show a positive result

California's winter wave appears to have either plateaued or started to decline.

For the week to Jan. 20, there were 2,975 new COVID-19 hospitalizations, down 10% from the prior week. The seasonal high thus far was 3,746 for the week that ended Dec. 30. This was lower than the prior winter's peak of 5,260 during the last week of 2022.

The first two winters of the pandemic were the most deadly for California and strained hospital systems. The peak for new hospitalizations during the first winter was 16,663, for the week that ended Jan. 9, 2021.

In Los Angeles County, virus levels in wastewater appear to be plateauing. For the week that ended Jan. 13, the most recent available, levels reached 67% of last winter's peak.

However, in the San Jose area, virus levels as of Jan. 21 were at their highest level for the winter, comparable to the first Omicron wave two years ago.

Statewide data from Kaiser Permanente indicate that COVID-19 may be plateauing, flu is on the way up, and respiratory syncytial virus might be starting to come down, Dodd said.

In L.A. County, flu and RSV levels have lowered but remain elevated, the Department of Public Health said.

Dodd continues to recommend COVID-19, flu and RSV immunizations.

While COVID-19 has become less deadly, it remains a significant public health challenge. Since Oct. 1, at least 24,000 COVID-19 deaths have been reported nationally, including at least 1,900 in California.

"COVID-19 continues to cause more hospitalizations than influenza and respiratory syncytial virus," the CDC said in a statement last week.

Flu is also playing a significant role at emergency rooms.

"Right now, more people are going to emergency departments to get care and being diagnosed with flu than COVID-19," the CDC said.

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This story originally appeared in Los Angeles Times.