I am on a contingency planning team to try and offer guidance to the members of our organization who have remained in Mexico. One area of discussion that has come up in the team as we are drafting recommended action plans revolves around the amount of time people should continue self-isolation after possible COVID-19 symptoms have resolved.
The CDC says at least seven days after the onset of symptoms and only after 72 hours of normal temp and no symptoms without the use of fever reducers.
The UK’s NHS says seven days after the onset of symptoms if fever is normal with no fever reducers.
The director of the WHO said in a speech that “People infected with COVID-19 can still infect others after they stop feeling sick, so these measures should continue for at least two weeks after symptoms disappear.” (Referring to no visitors and caregivers washing hands after contact and wearing masks.)
Someone cited some study that said, " Shedding of viral RNA from sputum outlasts the end of symptoms and may occur for up to 21 days." They assumed that meant you are contagious for up to 21 days after no symptoms, but I don’t think that is what it means, since the same study also said, " No patient has had a positive viral culture more than 8 days after symptom onset." Another article I found said:
“Importantly, the scientists could not grow viruses from throat swabs or sputum specimens after day 8 of illness from people who had mild infections.”
“Based on the present findings, early discharge with ensuing home isolation could be chosen for patients who are beyond day 10 of symptoms with less than 100,000 viral RNA copies per ml of sputum,” the authors said, suggesting that at that point “there is little residual risk of infectivity, based on cell culture.”
So my question is, where do we point people to the most recent, definitive guidelines for how long to do self-isolation (from family, everyone is already doing stay at home/ social distancing) if you think you have a mild case? Assume there is no availability of testing unless you require medical intervention or hospitalization.
I read some physician posts discussing the same thing. Hospitals administrators are forcing health care workers back to work after 72 hours of no fever, but that is a recipe for disaster as many are probably still contagious. I would go with the WHO recommendations, which is the consensus on the physician forums as well : two weeks after sysmptoms disappear. That is perhaps overly conservative, and perhaps could be relaxed a bit in low risk situations, but would be safest with our present level of knowledge.
In some of the stuff I’ve looked at, it has implied there is a difference between mild and more severe cases when it comes to how long you stay contagious. Do you think that is right? Also, they are saying that if you have symptoms, you should totally isolate yourself from the rest of your family. So, are you saying the doctors think you should stay totally isolated from your family for two weeks after symptoms, or just stay home (like in quarantine) for two weeks after symptoms?