[ballstothewalls]

Does anyone know the details behind the 21 day time period for declaring someone to be infection free? Is that some kind of biological max for how long the virus can live or is it a statistics thing where the virus is not there 95% of the time?

[tjohns]

Statistics. There have been rare cases of the incubation period being longer than 21 days, but most people will get sick much sooner. (95th percentile)

That said, there was a recent PLOS article that suggested that a longer waiting period might be called for: http://currents.plos.org/outbreaks/article/on-the-quarantine...

There's also a cost-benefit analysis involved here. More transmissible/serious diseases call for a larger margin of safety, while at the same time enforcing a longer quarantine takes a toll on total available infrastructure.

[ballstothewalls]

Thank you for the link!