Some more quotes:
https://www.nytimes.com/2020/12/02/health/coronavirus-quarantine-period.htmlTravelers returning home should keep nonessential activities to a minimum for at least seven days if they are getting tested, and for 10 days if they are not getting tested. (Many states already require travelers to self-quarantine after arrival, though the rules vary from state to state.)
Federal health officials also offered two new ways to shorten quarantine periods. Those without symptoms may end quarantine after seven days if they are tested for the virus and receive a negative result, or after 10 days without a negative test.
P.C.R. or rapid tests are both acceptable, the officials said, and should be taken within 48 hours of the end of the quarantine period. People should continue to watch for symptoms for 14 days.
(Quarantine refers to people who are well but may become ill; isolation refers to those known to be ill.)
Until now, the C.D.C. has recommended a 14-day quarantine period following potential exposure, and Dr. Walke stressed that the full two weeks is still considered ideal and the surest way to curb transmissions.
While a shortened quarantine period may be more palatable to Americans, officials acknowledged that the new guidance might lead to some infections being missed.
“We can safely reduce the length of quarantine, but accepting that there is a small residual risk that a person who is leaving quarantine early could transmit to someone else if they became infected,” said Dr. John Brooks, the chief medical officer for the Covid-19 response at the C.D.C.
Some patients may not develop symptoms until two weeks after exposure, and even longer in a very small fraction of cases. Infected individuals may pass the virus to others before they develop symptoms; recent studies show they are most infectious two days before symptoms begin, and for about five days afterward.
https://www.cdc.gov/media/releases/2020/t1202-covid-19-telebriefing.htmlBUSINESS INSIDER: HI, YEAH, THANKS FOR TAKING MY CALL. MY QUESTION. I WANTED TO ASK MORE SPECIFICS ABOUT THE TESTING OUT OF QUARANTINE. WHEN IS THE BEST TIME TO DO THAT? SHOULD PEOPLE GET A TEST ON THE FIRST DAY OF QUARANTINE, ON THE FIFTH DAY OF QUARANTINE? TALK ABOUT LIKE WHEN IS THE BEST TIME?
BROOKS: WELL, THE RECOMMENDATION FOR DISCONTINUATION OF QUARANTINE IS DAY SEVEN WITH A NEGATIVE TEST. OUR MODELLING SHOWS — LET ME REPHRASE THAT OUR MODELLING WAS BASED ON COLLECTING THE SPECIMEN WITHIN THE 48 HOURS PRIOR TO THE TIME OF ANTICIPATED DISCHARGE. SO IT COULD BE A TEST THAT WAS DONE THAT DAY IF YOU HAVE AN ANTIGEN TEST, BUT WE PROVIDE THE POSSIBILITY OF COLLECTING SPECIMEN UP TO 48 HOURS BEFOREHAND IF THEY HAVE A PCR TEST WHICH MAY TAKE A DAY OR TWO TO GET THE RESULT BACK.
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BROOKS: THAT’S RIGHT. THEY COULD BE TESTED ON DAY FIVE IF THAT — BUT THEY HAVE TO COMPLETE SEVEN DAYS OF QUARANTINE. I WANT TO BE CLEAR ABOUT THAT. IT CAN BE ANY TIME IN THE 48 HOURS PRIOR TO THE ANTICIPATED TIME OF DISCHARGE, BUT THEY DO HAVE TO GET ALL THE WAY TO THE END OF SEVEN DAYS REGARDLESS OF WHEN THE RESULT OF THE TEST COMES BACK. IF THE TEST HASN’T COME BACK BY THE END OF SEVEN DAYS, THEY CAN DISCONTINUE QUARANTINING WHEN THEY GET THE NEGATIVE RESULT. THEY NEED THE NEGATIVE RESULT TO DISCONTINUE.