I hung out, socially distanced and masked, with someone who later tested positive. Have I been exposed?

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.

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.

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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.”

Like Swiss cheese, protective measures like social distancing, wearing a mask, hand washing, and testing all have holes that the virus can move through. But the more you layer those together, the greater the chance you have of covering up those holes and protecting yourself and others. Getting vaccinated will likely become your least hole-filled layer of protection.

One important measure to consider is whether you were hanging out inside or outside.

“The setting really matters here,” says Krys Johnson, an epidemiologist and assistant professor at Temple University. “If you’re wearing masks and social distancing, but you’re in a small room together, that’s still going to lead to an increased risk. The longer you sit in an enclosed space, the more viral particles build up in the air.”

Better ventilation allows virus particles to more easily disperse. When you are masked and maintaining social distancing, being outdoors will gain you more confidence that your exposure risk was low. Either way, experts advise remaining extra cautious for the next 14 days or getting tested.

If it’s feasible, LeVasseur recommends quarantining as if you were considered a close contact.

“It’s not a quarantine in any kind of mandated way, but in the ‘I don’t want to infect the people I’d be spending time with’ way,” says LeVasseur. “We have this new variant that’s 56% more infectious. Now is not the time to let down our guard.”

There are now multiple new coronavirus variants circulating globally. While there’s no evidence that they cause more severe illness, mutations originally found in the United Kingdom and South Africa have proven to spread more quickly and easily.

“The virus is already overwhelming hospitals,” says Johnson. “There’s really no room for error.”

We’re advised to keep hangouts with those outside of our household to a minimum regardless. Even if you were at a distance, if you were with someone who tests positive, experts encourage acting with an abundance of caution.

But let’s say you have an in-person job, and imposing a self-quarantine isn’t realistic. Then what? Double down on the safety precautions you’re already taking.

“Make sure you’re wearing your mask at all times, and you’re not around folks who aren’t wearing masks,” says Johnson. “Depending on what your employer’s policy is, you might want to let them know. Some may be more willing to allow people to take paid time off.”

Testing may help alleviate some of your anxiety. But you may not be able to get tested immediately after finding out about potential exposure. The best time to get tested is five to seven days after your last contact with the person who was infected.

“The worst thing you can do is go get tested too early, it’s negative, and then [a couple days later] you go see your grandmother, and you end up being presymptomatic or asymptomatic,” says Johnson.

Bottom line: If you end up hanging out with someone (masked, at a distance) who tests positive, rather than driving yourself crazy with anxiety, empower yourself in the situation by practicing extra caution. Until the pandemic ceases and hospital beds free up, erring on the side of safety will always remain the prescribed advice.

“I encourage a level of anxiety where you’re going to take steps to prevent spreading the virus to others,” says LeVasseur. “The right way to think about it is being responsible — to your loved ones, your neighbors, your community.”

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