When the Covid public health emergency expired in May, health officials in Oregon decided it was also time to withdraw the recommendation that its residents, including schoolchildren, self-isolate for five days after testing positive for the virus.

Instead, the Oregon Health Authority suggested that people with covid stay home only until they have been fever-free for 24 hours and are generally feeling better.

The move was a break with guidance from the Centers for Disease Control and Prevention, which continues to recommend that people stay home for a while. five day period and stay away from household members.

«Covid hasn’t gone away,» said Dr. Dean Sidelinger, state epidemiologist with the Oregon Health Authority, «but based on what we’re seeing in Oregon, it looks like we’re moving in the right direction.»

Covid-related hospitalizations have declined in Oregon, and wastewater monitoring indicates the spread is holding steady or declining.

Also, «our immunity level is high,» Sidelinger said. «That made us feel comfortable moving to a symptom-based isolation recommendation.»

National Covid trends are similar, according to CDC tracking. The agency won’t say if it plans to update its isolation guidance any time soon.

«CDC continually reviews its guidance for necessary updates and recognizes that states may choose to implement CDC recommendations based on the needs of their own communities,» Kathleen Conley, an agency spokeswoman, wrote in an email.

With much of the Covid testing done in private or not done anymore, many Americans probably won’t bother to self-isolate anyway.

So who follows the CDC guidance? Schools, nursing homes and shops.

How long should you really isolate yourself?

The current recommendation to isolate for five days is a «hangover» from when the CDC moved from a 10-day isolation recommendation to five days in late 2022, just as the first wave of omicron was taking over the US. said the epidemiologist at Harvard University. Bill Hanage.

«It was not a reflection of evidence-based science,» he said. «I was there to keep everything from falling apart.»

More about omicron and being contagious

At the time, a large part of the population was testing positive at once for the highly contagious variant. Recommending that everyone stay home, and without work, for 10 days would have brought the country to a standstill once again, so the five-day plan was implemented.

“If you look at the safety of the public and the need for society to be unaffected, this was a good choice,” Dr. Anthony Fauci, a former science adviser to the Biden administration, said at the time of the isolation recommendation.

There was also evidence that people are more contagious during those first five days of infection. That remains the most reliable scientific data, experts say.

«We know that most people with COVID-19 shed enough virus to remain contagious for at least five days,» Jennifer Nuzzo, a principal investigator at the Johns Hopkins Center for Health Security, wrote in an email.

“The end of the public health emergency declaration does not change biology,” Nuzzo wrote. «I don’t see a biological reason to end the five-day isolation period.»

What we know about being contagious

People with the flu are most contagious the first three to four days after their illness begins, according to the CDC. people who test positive for influenza they are advised to stay home «until at least 24 hours after fever is gone» without the use of fever-reducing medications, such as Tylenol.

A common cold virus is most contagious in the first few days, but can continue to spread for up to two weeks, according to Johns Hopkins All Children’s Hospital investigation.

Like other viruses, people with covid have varying degrees of illness.

A set number of days to isolate is «silly if you think about it from a medical perspective,» said Dr. Peter Chin-Hong, an infectious disease specialist at the University of California, San Francisco.

“If you feel fine the full five days and you have absolutely no symptoms, staying home alone is not the same as someone who has had symptoms and then after five days they go out and cough everyone up,” Chin-Hong said. «The symptom approach makes the most sense, not just for covid, but for many other infectious diseases that people don’t normally isolate themselves for.»

It is not appropriate to compare Covid with the flu, Nuzzo insisted.

“The flu is not still killing hundreds of Americans every day, but Covid-19 is,” he said.

Chin-Hong agreed, saying that having so many deaths from covid in 2023 is a «tragedy.» That is why the issue of insulation is so complicated.

‘If you’re sick, stay away from people’

While Chin-Hong believes the changes the Oregon Health Authority made are «reasonable,» she said the time for a nationwide symptom-based approach is not yet.

Oregon is the only state so far that has relaxed its isolation guidance, said Dr. Anne Zink, president of the Association of State and Territorial Health Officers.

Some state health officials said they feel more comfortable sticking to the five-day isolation guidance, with the caveat that «no protocol, no CDC recommendation, no state recommendation will work for all situations,» said Zink, who also is medical director for the Alaska Department of Health.

For example, Alaska health authorities have upheld the recommendation to self-isolate for five days after testing positive for Covid. But they also work with local jurisdictions and businesses to assess the risks and benefits of that guidance, Zink said.

«What’s going to work in Utqiagvik, Alaska, compared to the Bering Sea and Anchorage, will be very different,» Zink said. «The way people in our state live, work and play is so different, so we point them to the CDC guidance and then explain to them on an individual basis» whether self-isolation is the right approach.

At the individual level, common sense should rule, Hanage said. If you are sick, stay away from people who are most at risk of serious complications, such as elderly relatives.

«You wouldn’t want to give them something that would make them seriously ill, whether it’s covid, flu or even food poisoning,» he said.

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