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The US Centers for Disease Control and Prevention recommends that people with Covid-19 isolate for at least five days, but recent policy changes in California and Oregon break from that guidance.
CNN  — 

People who test positive for Covid-19 in California and Oregon are no longer expected to isolate for a set period of time — and those without symptoms don’t have to isolate at all, state policies now say. People with symptoms can return to school or work once their symptoms are improving and they’ve been fever-free for at least 24 hours, according to the state policies.

These two states — which have tended to take a more precautious approach to pandemic policies — are the first to break from federal guidance from the US Centers for Disease Control and Prevention, which recommends at least five days of isolation for anyone with Covid-19. Oregon changed its isolation policy in May when the Covid-19 public health emergency lifted, and California followed suit earlier this month.

Officials in both states say the changes reflect policy that’s evolving along with the pandemic.

“We are now at a different point in time with reduced impacts from COVID-19 compared to prior years due to broad immunity from vaccination and/or natural infection, and readily available treatments available for infected people,” Dr. Tomás Aragón, director of the California Department of Public Health, wrote in the official order about the change. “Our policies and priorities for intervention are now focused on protecting those most at risk for serious illness, while reducing social disruption that is disproportionate to recommendations for prevention of other endemic respiratory viral infections.​”

The CDC recommends at least five days of isolation because people are likely to be most infectious during that time, and the science around that hasn’t changed. The recent order from the California health department notes that the potential infectious period spans from two days before through 10 days after symptoms or a positive test.

But experts broadly agree that easing isolation timeframes won’t significantly increase community transmission or severe outcomes — in part because the virus has been circulating at very high levels, even with more restrictive guidance in place.

“I don’t think this is reflecting updated science, but this is reflecting changing social norms and increasing workplace crunches,” said Jennifer Nuzzo, an epidemiology professor and director of the Pandemic Center at Brown University School of Public Health.

Recent data from Oregon suggest the policy change has had minimal effect on virus trends. The state has seen a surge this winter, like the rest of the country, but Covid-19 hospitalization rates and emergency department visits have stayed below the national average, according to data from the CDC.

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“We are not going to be able to completely stop transmission, and we’re not going to be able to get rid of this virus in the human population,” said Dr. Dan Barouch, director of the Center for Virology and Vaccine Research at Beth Israel Deaconess Medical Center. “Then, the decision of how to bring something into policy is really a summation of the medical risks as well as the risks to society as a whole.”

Instead, as the burden of severe disease has lessened, some experts say that stricter isolation policies may have unintended negative effects on public health.

“When we’re sick, we typically want to know what we have so that we can get treatment and possibly feel better,” said Dr. Sarita Shah, a clinical care provider and infectious disease epidemiologist at Emory University. “The ironic thing is, what I think has happened with Covid because of the isolation policies is that people kind of don’t want to find out because it leads to negative things.”

People with mild symptoms may not test because they can’t afford to miss a week of work and they might avoid wearing a mask because it could raise questions, she said. Less restrictive isolation policies could allow people to feel more comfortable with testing, which could prompt them to get treatment or feel more comfortable taking other protective measures.

Dr. Dean Sidelinger, Oregon’s state health officer, said that equity was a key factor considered in the decision to change isolation policy in the state.

“From a pragmatic standpoint, from an evidence-based and equity standpoint — trying to make sure that we weren’t unnecessarily burdening families, keeping kids out of school, or keeping people out of work who may have very limited sick leave — this made sense for us,” he said.

Public health policy decisions are rarely black-and-white, experts say, and weighing tradeoffs can be more of an art than a perfect science.

“There are different perspectives on the best way forward, even with everyone looking at the same data, everyone with the same good intentions in mind,” Barouch said.  “Well-meaning people could come to different conclusions.”

The CDC says that it will “continue to evaluate the latest data, including the continued decline in hospitalizations and COVID-related deaths compared to last year – likely the result of widespread vaccination and prior infection – as it considers its recommendations for how people can best protect themselves and their loved ones from the virus.”

But the agency notes that local jurisdictions have “shaped health guidelines to address situations on the ground” since the start of the pandemic.

In many ways, the changes California and Oregon made to their isolation policies for Covid-19 put it more in line with the way public health approaches other respiratory viruses, experts say. For example, if a child has a mild sore throat or fever, the decision about whether to go to school or not shouldn’t depend on the results of a Covid-19 test.

“It’s really challenging to have disease-by-disease policies in a respiratory season for which we don’t have ubiquitous testing,” Nuzzo said. People who are sick should take precautions, she said, and “we should be using tests as a tool, not as a penalty.”

While severe outcomes for Covid-19 have decreased over the years, it is still not just a cold, or even like the flu. The latest CDC data shows that Covid-19 hospitalization rates have consistently been at least twice as high as they’ve been for flu this respiratory virus season, and thousands of people have died from Covid-19 in the first two weeks of this year.

This ongoing burden of disease is why there is such strong debate about policy change, Shah said.

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But the tools we have to manage Covid-19 have evolved rapidly and are much more in line with what’s available to manage other respiratory diseases, experts say — and isolation is just one strategy. Oregon and California, for example, still encourage people who test positive to wear a mask for at least 10 days.

Also, the policy changes in California and Oregon offer a broad, population-level approach to Covid-19 management. But individuals and places like hospitals may adjust based on their own risk tolerance.

“Health decisions generally are individual. At the end of the day, you’re always having that discussion with your doctor about what’s going to be best for you,” Shah said. The same internal analysis has now been happening around Covid-19 for years, and the risk-benefit balance may have shifted for many people, she said.

“I think it’s time to have that conversation and to have that debate.”