Reader question: How long can you be contagious after testing positive for COVID-19?

A person with COVID-19 may be contagious 48 to 72 hours before starting to experience symptoms, which are thought to start three to 14 days after they are exposed to COVID-19, according to Harvard Health Publishing, a consumer health education division of Harvard Medical School.

Emerging research suggests that people may actually be most likely to spread the virus to others within 48 hours before they start experiencing symptoms. Research also shows people who are infected and asymptomatic may be more likely to spread the illness because they are less likely to be isolating or adopting behaviors designed to prevent spread.

The Centers for Disease Control and Prevention says a person who thinks or knows they had COVID-19 and experienced symptoms can be around others after 10 days have passed since symptoms first appeared, they’ve gone 24 hours with no fever without using fever-reducing medications and have seen improvement in other symptoms.

People with no symptoms who tested positive for COVID-19 can be around other people 10 days after testing positive for the virus, according to the federal agency.

There are documented exceptions so some experts still recommend 14 days of isolation.

As for the antibiotics you said these people received antibiotics do not prevent or treat the coronavirus because it is caused by a virus, not bacteria.

Some patients with COVID-19 may also develop a bacterial infection, such as pneumonia. In that case, a health care professional may treat the infection with an antibiotic but will not use antibiotics to treat COVID-19.