But some scientists have also focused on tinier particles called aerosols. These can linger in the air for minutes to hours, and spread through a room and build up in concentration if ventilation is poor, posing a potential risk of infection if inhaled.
For aerosols, “6 feet is not a magic distance” and keeping even farther apart is better, says Linsey Marr, who researches airborne transmission of infectious diseases at Virginia Tech.
Some scientists say there’s enough evidence about aerosols and the virus to take protective measures. In addition to the usual advice, they stress the need for ventilation and air-purifying systems when indoors. Even better, they say, is to stay outdoors when interacting with others.
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