Exams additionally differ of their sensitivity, and other people differ in how they carry out them. “Some folks do a swab check and it’s like they barely contact their nostril,” Dr. Gordon mentioned. “Whereas with different people — truly, with a member of the family lately, I needed to be like, ‘Don’t damage your self,’ as a result of they have been actually, actually getting in there.”
What to do
One lesson is that extended optimistic outcomes are widespread sufficient that individuals who depart isolation earlier than Day 10 ought to proceed to take precautions, akin to sporting a well-fitting masks, specialists mentioned.
Past that, scientists disagreed. Some beneficial that individuals isolate till they check antigen-negative, even when it takes greater than 10 days.
“We will now tailor suggestions to particular person experiences utilizing the speedy check outcomes to information us,” Dr. Grad mentioned. “And since we all know that some folks can have extended programs, it appears affordable to me that if you’ll be able to proceed isolating if optimistic, it is best to accomplish that.”
However a number of others mentioned that, as a matter of public well being coverage, it doesn’t make sense to ask most in any other case wholesome folks to isolate, and even preserve testing, for greater than 10 days.
“No person’s saying that there aren’t some folks, perhaps statistically talking on the finish of the tail, who would possibly transmit after Day 10,” Dr. Chin-Hong mentioned. However folks at that stage of an infection wouldn’t be more likely to play a big function in spreading the virus, and continued testing might preserve many individuals out of labor or college with out a lot public well being profit, he mentioned. “And in addition you elevate an fairness problem,” he added, “like, ‘Who on Earth can have sufficient checks?’”
Even then, specialists say, there are some circumstances by which folks ought to proceed to check and probably isolate past Day 10. They embrace folks whose signs aren’t enhancing and people who are immunocompromised, as they might shed infectious virus for longer durations of time. (The C.D.C. recommends that individuals with weakened immune programs isolate for up to 20 days.)