1 / 11Thousands of droplets from the mouths of people who are talking loudly can stay in the air for between eight and 14 minutes before disappearing, according to a new study.2 / 11The research, conducted by a team with the US National Institutes of Health and published in PNAS Wednesday, could have significant impact on our understanding of covid-19 transmission.3 / 11Respiratory viruses like SARS-CoV-2 are transmitted either by direct contact or when the virus hitches a ride on tiny droplets released into the air by a carrier. 4 / 11The researchers asked people to repeat phrases and used sensitive lasers to visualize the droplets they produced, watching them decay in a closed, stagnant air environment. 5 / 11On the basis of previous studies of how much viral RNA can be found in oral fluids in the average covid-19 patient, the researchers estimate that a single minute of loud speaking generates at least 1,000 virus-containing droplets.6 / 11Their observations suggest these droplets stay airborne for longer than eight minutes, and sometimes as long as 14 minutes.7 / 11The study’s hypothesis assumes that each virion has an equal, non-zero chance of causing an infection, which is far from certain for covid-19.8 / 11The study was also run in a tightly controlled environment, and it did not account for the types of air circulation and temperature changes you would find in nearly any real-world environment.9 / 11Still, it raises serious concerns that the mere act of an infected patient talking could be dangerously effective in transmitting coronavirus to others.10 / 11 The researchers write that their estimates are conservative; some patients produce a much larger amount of the virus than average, which could increase the number of virus-containing droplets “to well over 100,000 per minute of speaking.” 11 / 11The biggest impact of the findings might be in reinforcing the necessity to wear masks under any circumstances when leaving the house, to avoid possible transmission.