By Julie Steenhuysen

CHICAGO (Reuters). Despite halving the time for isolation of COVID-19-related infections, new U.S. guidelines lack safety measures that could increase the risk as the country faces a record number of Omicron variant infections.

    This week the U.S. Centers for Disease Control and Prevention reduced the recommended isolation period for people with asymptomatic COVID to five days, down from 10, after which they are asked to wear masks for an additional five days. Omicron has spread rapidly, which may force more people from different industries to return home within the next week, even though they’re not sick or infected.

Scientists have expressed concern that the isolation policy doesn’t distinguish between people who are vaccinated from those who are not. They recover from the virus in different ways. The testing is not required to prove that someone isn’t infected before they return to work and socialize.

    “Unvaccinated people take much longer to clear the virus and not be infectious,” said Dr. Eric Topol, director of the Scripps Research Translational Institute. The virus can be cleared in as little as a day for some people, but others need to wait up to seven days.

Topol stated that the policy was a “new low” for CDC and contradicts the Biden administration’s promise to abide by scientific evidence in order to reduce the pandemic.

Topol, along with others, stated that not enough evidence was available to support Omicron’s five-day isolation recommendation. They also questioned the decision to treat unvaccinated patients the same as vaccinated, and that testing requirements were absent at the end.

Rochelle Walensky, Director of the CDC, stated Wednesday that this decision was based upon research that showed that as much as 90% of transmission of COVID occurred within 5 days. The agency countered that statement with the evidence that only a few people suffering from COVID were willing to stay isolated for 10 days during this pandemic.

Walensky spoke to CNN in an interview.

A number of countries have also reduced quarantine or isolation times. However, this decision is based on past variations and early Omicron research that doesn’t include potential surprises. Mike Ryan, the World Health Organization’s chief emergency expert, stated that there are many other countries that did so.

Ryan said at a Geneva news conference on Wednesday that “it would be wise at this point not to see large shifts in controlling COVID-19’s control measures solely on the basis or preliminary studies.”

    TREMENDOUS DISRUPTION

    The average number of daily U.S. COVID cases hit a new all-time record on Wednesday of nearly 260,000 infections. Although many cases of COVID are not serious or even symptomatic, there is a national labor shortage because of the high number of Americans that would have to be quarantined or isolated due to confirmed infections.

This has led to the worst economic impact on the airline industry, with thousands of cancelled flights in the winter holidays while crew members go home.

According to Dr. David Dowdy at Johns Hopkins University, “If all these people suddenly go out of work for two or more weeks, it will cause great disruption.” There is no simple answer.

    Others warned the new guidance could inadvertently fuel additional cases.

    Dr. Megan Ranney, academic dean of public health at Brown University, compared the new isolation policy to a widely-criticized CDC decision in May 2021 to drop a mask recommendation for fully vaccinated people in indoor public spaces. This resulted in many people not being vaccinated wearing masks inside, leading to more infections.

While the goal of changing mask policy was to make it easier for Americans to get vaccinated in general, this change relied on compliance by unvaccinated persons, many of which were opposed to indoor mask wearing.

Americans are required to wear masks five days following the end of their isolation period. This is in addition to testing.

Ranney stated, “We know people don’t wear masks at the moment.”

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

    “Making a policy recommendation like that would have taken this from a bad policy that everybody’s upset about to a very reasonable policy that is based on evidence,” said Dr. Angela Rasmussen, a virologist at the University of Saskatchewan in Canada.

    Given the persistent test supply shortages, though, requiring rapid tests would have been “almost laughable,” Ranney said. There is a difference between the ideal science, and what actually happens on the ground.