Wag the dog: PCR tests for day trips to US
Requirement: Negative PCR test within 72 hours of re-entry
I'm going to analyse this requirement based on health, not cost.
Let's assume the reason is to stop COVID from entering Canada.
You go to the US for 1-2 days
You get exposed to the virus
Before re-entry, you manage to get a PCR test with immediate results
It will not be positive because the incubation period is not complete
Typically, PCR tests do not show infection until after 3-5 days of incubation
You would have to be away for at least 3 days, most likely more, before the PCR test requirement makes sense
But, the government says that, for short trips, you can take a test in Canada before you cross to USA
A perfect example of the tail wagging the dog
It allows you to meet the “within 72 hours” requirement, but does not meet the objective of stopping COVID from entering Canada, because again, it would only show a positive result if you were exposed 3-5 days before the test (when you were still in Canada)
Am I missing something…???
Sources
It can take almost a week after exposure to COVID-19 to have a positive test
testing tends to be least-accurate in the first three days after
It’s most reliable to get tested for COVID-19 five to seven days after your exposure
the probability of a false negative on the PCR test went from 100 percent on Day 1 to 67 percent on
it would be exceedingly rare for anyone to transmit the virus earlier than two days post
It’s recommended that you wait to get tested for at least two to three days after potential exposure. Some health experts say
"Someone can get a positive [COVID-19] test result as soon as two days after exposure, but we typically ask our patients to wait at least five days for most accurate