We've heard it before: Wear a mask, practice social distancing, avoid crowds, and wash our hands regularly. These are all important ways to protect ourselves from the coronavirus and from spreading it to others.
But what happens if you took those safety precautions and were hanging out with a friend who later tests positive for the coronavirus? If you were both wearing masks and stayed six feet apart, do you need to be concerned about having been exposed?
Here's what you should know.
HOW THE CDC DEFINES ‘CLOSE CONTACTS’
Close contacts are the people contact tracers track down and advise to quarantine and get tested after being exposed to someone with COVID-19. The Centers for Disease Control and Prevention defines a close contact as anyone who was within six feet of an infected person for a minimum of 15 minutes within a 24-hour period, starting from two days before illness onset (or, for asymptomatic people, two days prior to getting tested) until the time the person is isolated.
If you don't fit this criteria, you won't get a call from contact tracers, even if you've hung out with someone who ends up testing positive. And you're not obligated to quarantine under CDC guidelines (14 days after your last contact with the person who has COVID-19).
Experts say, however, that doesn't necessarily mean you weren't exposed.
THERE ARE FACTORS BEYOND SOCIAL DISTANCING AND THE 15-MINUTES RULE
There are many factors that affect the spread of the coronavirus, including ventilation, whether the infected person already had symptoms or not, and what kind of activity you were doing. Being around someone for less than 15 minutes doesn't completely eliminate your risk of becoming infected. Neither does staying six feet apart. But both measures help contact tracers narrow down who should quarantine and get tested after an exposure.
"There are shades of concern. As epidemiologists, we've more recently been looking at what we call the Swiss cheese model of protection," says Michael LeVasseur, assistant professor of epidemiology and biostatistics at Drexel University. "Each layer of defense is not perfect, but when you line them all together, they offer much stronger protection."