A driver is tested for coronavirus infection at a site in Oakland, Calif., Nov. 19, 2020.
In September, France dropped its required period of isolation to seven days from 14 days, and Germany is considering shortening it to five days. Cevik and her colleagues set out to analyze the so-called kinetics of the coronavirus over the course of an infection, and to compare the pathogen to the closely related severe acute respiratory syndrome and Middle East respiratory syndrome viruses.
A few patients may carry infectious virus in their lungs — as opposed to the nose and throat — for as long as eight days after symptoms begin, noted Dr. Megan Ranney, an emergency physician at Brown University. For these patients, at least, isolation periods should probably be longer than five days, if only they could be identified.
The analysis underscores data that has accumulated since March. In July, based on similar evidence, the CDC truncated its recommendation for isolation to 10 days from 14 days. Some people who are older or very sick may be infectious for longer than a week. But if a shorter recommended period encourages more people to isolate, the benefit will more than offset any risk to the community from the small amount of virus that a few patients may still carry after five days, said Dr. Stefan Baral, a public health researcher at Johns Hopkins University.
But Bell said he was unsure how this would work in practice, because these early symptoms were similar to those from other viral infections, including the common cold.
Should only be isolated if they don't know how to take precautions not to spread whatever they have. The rest of the world has been doing it for a century...we are just learning to crawl in that respect.