- Despite nationwide instructions to practice social distancing, many people still wonder whether it's possible to contract COVID-19 even when you're not near others, if the virus is airborne.
- Recent research suggests that contagious novel coronavirus particles can linger in the air for a few hours.
- Health officials recently said that new coronavirus particles can become airborne from talking or even just exhaling.
- Infectious disease experts still do not think that COVID-19 viral particles spread across far distances.
As social distancing has become the new normal amid the novel coronavirus pandemic, you may have wondered whether it's still a potential risk to share space and cross paths even at a distance. After all, if people without symptoms can pass it on, could this mean that any time you leave your house you might be exposed to the virus wafting through the air?
Health officials think yes. For example, in an update last week, Harvey Fineberg, MD, PhD, chairman of a committee with the National Academy of Sciences, said that COVID-19 (the illness associated with the new coronavirus) can spread via talking or even breathing.
"Some of us by talking or even breathing produce a number of these tiny bioaerosol particles, and those effectively can float around for a while," he explained further in an interview with NPR. He also pointed out that this is a problem mainly in enclosed spaces, like patient-care rooms. When you are outdoors and practicing social distancing, however, those particles get dispersed in the outside environment (like if they're blown around by the wind, for instance). "There's no real danger from that," he noted.
Because this is a brand-new coronavirus, the Centers for Disease Control and Prevention (CDC) acknowledges that "we are still learning how it spreads, the severity of illness it causes, and to what extent it may spread in the United States." So, yes, more research is needed for a definitive answer to this question, although infectious disease experts can shed some light on what they know so far about whether or not the novel coronavirus can spread through the air.
So...is the novel coronavirus airborne?
The short answer is: likely yes, but it's complicated. First, it's important to note that airborne can mean different things to different people, even experts. In general, a pathogen is considered airborne when it can spread via smaller particles that can remain in the air for long periods of time, says Natasha Bhuyan, MD, a specialist in infectious diseases and family physician in Phoenix, Arizona. The exact length of time that viral particles in general hang in the air before they dissipate depends on a variety of factors, including the temperature and humidity of the area, and so on, adds Rishi Desai, MD, a former epidemic intelligence service officer in the division of viral diseases at the CDC.
Now let's talk about the new coronavirus specifically: When someone who has novel coronavirus coughs or sneezes, the tiny droplets that come out of their nose and mouth are like a tiny cloud of mist—and it’s possible that they linger, says Dr. Desai. Experts just don't know the concrete answer at this point for how long, be it a few seconds or more like hours.
It's also not totally clear how far those particles travel, although current research suggests the virus can spread most easily when people are within about 6 feet of each other. You may have seen recent headlines that COVID-19 particles can reach as far as 23 to 27 feet away from the origin point, after researchers shared this info in an article published by JAMA. However, some health officials warn this is misleading, and that the current CDC guideline to stay 6 feet away from others still stands (more on that later).
Are there any guesses on how long new coronavirus particles can stay airborne?
In a study published March 18 in the New England Journal of Medicine, researchers found that SARS-CoV-2 (the virus that causes the COVID-19 illness) remained contagious in aerosols, like droplets from coughing, for three hours.
It's worth pointing out, though, that the experiments performed in this study (which also looked at SARS-CoV-2 viability on plastic, copper, and more, in addition to aerosols) were done in a highly controlled laboratory setting. But the authors concluded: "Our results indicate that aerosol ... transmission of SARS-CoV-2 is plausible, since the virus can remain viable and infectious in aerosols for hours."
So does the stay-6-feet-away rule still hold true?
Right now, yes. Particles may travel through and linger in the air simply by talking or breathing near someone, as Dr. Fineberg said in a government letter at the beginning of April. So, viral particles could hang around even without the force of a cough or sneeze behind them. This is why it's still so important to maintain a 6-foot distance from others, even when you're just casually chit-chatting with someone.
But even if a mist of the novel coronavirus hangs around for hours around where a person breathed, coughed, sang, spoke, etc., the CDC maintains that "airborne transmission from person-to-person over long distances is unlikely."
Dr. Bhuyan reiterates that message, saying you’re still most likely to catch it directly from an infected person when they expel droplets containing viral particles, and those particles land on your face, body, or a nearby surface (where you could potentially pick them up and then touch your face, for example)—or you're close enough to breathe them in. And again, we’re talking pretty tight person-to-person contact.
New research continues to emerge about how COVID-19 spreads—and there’s still a lot to learn. So, it's important to take all info with a grain of salt as new discoveries pop up.
If COVID-19 is airborne, should I wear a mask when I'm out and about?
As cases of novel coronavirus go up, health officials are starting to recommend the general public wears fabric masks when going out for essential activities, like grocery shopping, as WH reported previously.
Dr. Fineberg also explained in his NPR interview: "My answer right now is that it would be prudent for all of us when we're out and about to wear a face covering." But the main reason isn't to protect yourself; it's to protect others, he explained. Because you can spread the virus unwittingly if you're asymptomatic or pre-symptomatic, you want to reduce the risk of spreading it to others by staying physically distant and blocking potentially dangerous particles from escaping you (like with a homemade nose-and-mouth blocker), even when you feel fine.
And I should still keep up with my other stay-safe measures, right?
You bet! Experts agree: The key to fighting this pandemic is reducing your exposure to the virus as much as you can. So keep doing what you’re probably already doing. Stay away from potentially sick people who may sneeze or cough (and if that’s you, stay at home to avoid spreading it and cover your mouth with your elbow or sleeve), make sure to clean and disinfect surfaces at home, wash your hands frequently (for at least 20 seconds!), and try to avoid touching your eyes, face, or mouth, says Dr. Desai.
When it comes to social distancing, remember the 6-feet rule (have you heard this enough times yet?); that’s the distance you need to keep between you and other people in order to reduce your risk of being exposed to the virus if they’re carrying it (even if they don't know it!). If you can avoid being in public places (e.g., the grocery store), do so. And if you do need to run errands, try to do them solo to avoid populating a shared space with more people than necessary.
As you settle in for the long haul, remember that everyone is in this together. And as backwards as it might seem, keeping a physical distance between you and others is one of the best ways you can show friends and family that you care, as well as the most at-risk for the novel coronavirus among us, including older people and those living with chronic conditions or compromised immune systems.
