Updated to differentiate isolation (for people who tested positive or are symptomatic) from quarantine (asymptomatic people with significant COVID exposure).
In any new disease there is a lot of testing and research that needs to take place before we can make generalizations. With COVID-19 out of an abundance of caution the recommendation was to assume contagiousness for 14 days after testing positive or from the first presentation of symptoms and to wait at least 72 hours after conclusion of fever beyond that point. This was a fairly liberal catchall to limit the risk of exposing others.
Now that there has been more data collected, it has been found that nearly all people stop shedding infectious viral particles within 8 days after testing positive or first presentation of symptoms and only 24 hours after conclusion of any fever beyond that point. Therefore the new CDC recommendations are to isolate for 10 days total. This is significant as it is nearly 1/3 less time away from family and work!
It is important to note that those with very severe COVID infections or those with significant immunocompromised state may remain contagious for a longer period of time (but reportedly no more than 20 days).
New data shows COVID is only contagious for 8 days (besides for immunocompromised patients or severe infections).
- 14 day isolation
- And 72 hours after last fever/symptoms
- If COVID testing was required, may be out of work for up to 90 days
- 10 day isolation
- And 24 hours after last fever/symptom
- No need for negative COVID testing
Quarantine (for an asymptomatic person who had significant COVID exposure) remains at 14 days as it may take a few days up to ~1 week for the infection to become viable at which point the 8-10 days of contagiousness begins.