Coughs Can Spread COVID Farther Than 6 Feet, Study Says
It's become an article of faith in the COVID-19 era: To avoid infection, practice social distancing in public, defined as staying six feet away from people who aren't in your immediate household. But in recent months, some research has indicated that distance may not be enough. The latest: a new study that found infectious droplets produced by coughs may travel farther than six feet. Read on, and to ensure your health and the health of others, don't miss these Sure Signs You've Already Had Coronavirus.
Cough droplets are large and heavy
Scientists in Singapore studied how droplets produced by a cough might travel to a person standing 1 meter (3.2 feet) and 2 meters (6.5 feet) away.
The researchers found that a person standing 3.2 feet in front of a simulated cough was covered by about 65% of all the droplets produced: Large and heavy, these droplets tend to drop to the ground—hence their name—and contain a "tremendous" amount of virus, the study's authors said.
At the officially sanctioned distance of 6.5 feet, they found that fewer droplets (which tended to be smaller) reached the other person—but the ones that did still contained enough virus to be infectious. "Viral exposure could increase significantly through successive coughs or higher viral loads," they noted.
More evidence that handwashing is important
While those smaller droplets may not be as easily inhalable through the mouth or nose, they could land on clothes or hands, creating a potential vector for transmission. "Droplet deposition on skin and clothes may not directly lead to infection," the researchers said. "However, secondary transmission modes, including face, mouth, or nose touching, need to be avoided. Hygiene measures such as washing of hands and exposed surfaces are highly recommended."
This isn't the first study to suggest that social-distancing guidelines might be due for a rethink. Scientists suspect that coronavirus can be "aerosolized"—or transmissible through those smaller, further-away droplets, which can hang in the air—and are trying to figure out how likely that is. An August report from MIT and the University of Oxford said that the six-feet recommendation is based on 80-year-old science about how far droplets travel before dropping to the ground, and recommended that other factors—including ventilation, crowd size, duration of exposure, and whether face masks are used—should also be considered when setting a safe social-distancing guideline.
Experts are also trying to understand how airflow can spread the virus indoors, and how particle size, viral loads and specific activities (such as singing and speaking vs. coughing and sneezing) may contribute to that.
How to stay healthy
As for yourself, do everything you can to prevent getting—and spreading—COVID-19 in the first place: Wear your face mask, get tested if you think you have coronavirus, avoid crowds (and bars, and house parties), practice social distancing, only run essential errands, wash your hands regularly, disinfect frequently touched surfaces, and to get through this pandemic at your healthiest, don't miss these 35 Places You're Most Likely to Catch COVID.