Analysis-No test, no problem? Experts question US new CDC policy on COVID’s isolation period Reuters

Author: Julie Steenhuysen

CHICAGO (Reuters) – New government regulations that halve the period of isolation of asymptomatic coronavirus infections have no guarantee that they could cause even more infections as the US suffers a record rise in Omicron-induced variants, disease experts say.

This week, the U.S. Centers for Disease Control and Prevention reduced the recommended isolation period for people with no symptoms of COVID to five days, from below 10, and then required them to wear masks for an additional five days. The agency mentioned the rapid spread of Omicron, which could force more industry workers to stay home in the coming weeks, even if they are not sick or infected.

One of the main concerns expressed by scientists is that the isolation policy does not distinguish between unvaccinated and unvaccinated people who recover from the virus at different rates. It also does not require testing to verify that a person is not infected before returning to work or socializing.

“People who don’t get vaccinated need a lot more to clean up the virus and not be infectious,” said Dr. Eric Topol, director of the Scripps Research Translational Institute. “Some people clear the virus in a day; others need a week or more.”

Topol said the policy represented a “new low” for the CDC, saying the Biden administration was opposed to a commitment to work closely on scientific evidence to reduce the pandemic.

Topol and others said there was no recommendation for a five-day isolation to know how Omicron behaves, a decision to treat vaccines and unvaccinated cases in the same way, and that there were no test conditions at the end of that period.

CDC Director Rochelle Walensky said on Wednesday that the decision was based on research showing that up to 90% of COVID transmission occurred within five days of infection. The agency said this was balanced by the fact that a small minority of people with COVID-19 were only ready to be isolated for 10 days so far during the pandemic.

“We really want to make sure that we had a guide at this point where we would have a lot of illness, that he could be caught, that he was ready to catch people,” Walensky said in an interview with CNN.

Walensky said in a White House statement on Wednesday that standard PCR tests could not be used to determine when a person could leave isolation because it could be positive for several weeks. He told CNN that it was not clear how fast antigen testing predicted whether people could transmit the virus at the end of the disease. However, last week the CDC leadership requested that these tests be performed on health workers before they could return to work.

Many other countries have shortened their isolation and quarantine periods, a lawsuit based on past variant studies and Omicron findings that do not take into account potential surprises, said Mike Ryan, the World Health Organization’s chief emergency expert.

“It would be useful at this time if we don’t see big changes, big moves to reduce control measures for COVID-19, based only on initial or preliminary studies,” Ryan said at a news conference in Geneva on Wednesday.

A HUGE INTERRUPTION

The average number of U.S. COVID-19 cases hit an all-time high on Wednesday, with nearly 260,000 infections. Although many of these cases are mild or symptomatic, the large number of Americans who would have to be isolated due to confirmed infection or quarantine as a result of exposure threatens to exacerbate the national labor shortage.

The airline industry has been the hardest hit so far, with thousands of flights canceled during the winter holidays as crew remain at home.

“If all of these people suddenly go out of work for two weeks, it will cause a tremendous disruption,” said Dr. David Dowdy, an infectious disease epidemiologist at Johns Hopkins University. “There is no easy answer here.”

Others warned that the new guidelines could feed more cases unnoticed.

Dr. Megan Ranney, academic dean of public health at Brown University, compared the new isolation policy to a highly criticized CDC decision in May 2021 to leave a mask recommendation for fully vaccinated people in public indoor spaces. As a result, many uninsulated people stopped wearing masks on the inside, probably encouraging new infections.

The change in mask policy was intended to encourage more Americans to be included, but was based on compliance by unvaccinated people, many of whom were already opposed to wearing masks indoors.

The new isolation policy is also based on the honest wearing of masks by Americans for five days after the end of the isolation period, rather than testing.

“We know people don’t wear masks right now,” Ranney said.

Shortening the isolation period for people with asymptomatic or very mild infections, as long as they get a quick negative test for COVID, may make more sense.

“Making such a policy recommendation would lead us from a bad policy that we all regret to a very sensible evidence-based policy,” said Dr. Angela Rasmussen, a virologist at the University of Saskatchewan in Canada.

Given the persistent shortage of test supplies, however, requesting quick tests “would be almost ridiculous,” Ranney said. “There is an ideal science and the real reality on earth.”