Do you have COVID-19 questions? Our scientists have answers.

When is someone infectious?

Generally, those infected with SARS-CoV-2 are most likely to be highly infectious a few days before COVID-19 symptoms start and the following five days.

The Centers for Disease Control and Prevention recommends quarantining for 14 days if an individual may have been exposed to the coronavirus so that that person does not spread COVID-19 to others. This is because COVID-19 symptoms may appear 2 to 14 days after exposure to the virus, and there is the potential to spread COVID-19 that entire time.

Updated 3 December 2020

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