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"COVID-19 is believed to spread through respiratory droplets when an infected person coughs or sneezes, or from coming into contact with an infected surface and then touching your eyes, nose or mouth.
There’s some evidence that COVID-19 may also be transmitted through much smaller airborne droplets in “very specific circumstances and settings,” such as “aerosolizing” medical procedures that cause the person cough or spit, such as suctioning or intubation, according to the WHO.
And in a letter to the White House, Harvey Fineberg, chairman of the National Academy of Sciences Standing Committee on Emerging Infectious Diseases and 21st Century Health Threats, also said that aerosolized droplets can be produced by simply talking or breathing, CNN reported Thursday. “Currently available research supports the possibility that [coronavirus] could be spread via bioaerosols generated directly by patients’ exhalation,” he wrote."