"[FONT="]That said, if you get a positive test, you almost certainly have COVID-19 —[/FONT] the false positive rate is very low[FONT="] — less than one per cent of tests overall, estimates Dr. Philippe Lagacé-Wiens, a medical microbiologist at St. Boniface Hospital in Winnipeg.
[/FONT][FONT="]On the other hand, MacDonald said you can't have the same confidence about a negative test, as it [/FONT]may simply mean you have been tested too early, before viral levels are high enough to be reliably measured[FONT="]. That's why people with symptoms who get a negative test result are told to self-isolate anyway.
[/FONT]https://www.cbc.ca/news/health/how-soon-should-you-be-tested-after-exposure-for-covid-19-your-questions-answered-1.5593840
[/FONT][FONT="]On the other hand, MacDonald said you can't have the same confidence about a negative test, as it [/FONT]may simply mean you have been tested too early, before viral levels are high enough to be reliably measured[FONT="]. That's why people with symptoms who get a negative test result are told to self-isolate anyway.
[/FONT]https://www.cbc.ca/news/health/how-soon-should-you-be-tested-after-exposure-for-covid-19-your-questions-answered-1.5593840