One of the common ways of COVID-19 spread is by droplets that are expelled out when an infected person coughs or sneezes. If a healthy individual is in a close distance, usually within a meter from the infected person, these droplets may directly reach the mucus membranes (eyes, mouth or nose) of the healthy individual spreading the infection. These droplets are so heavy that they don’t usually float in the air. As soon as they are generated by coughing or sneezing, they settle down on the floor or other objects nearby.
Occasionally, when the infected individuals have severe coughing and sneezing, they may produce few small particles that may remain suspended in the air. These small particles are called ‘droplet nuclei’. Based on the study published in New England of Journal of Medicine, these droplet nuclei may remain floating in the air for about 3 hours. It is rare that Novel Coronavirus spreads through air in the community as these droplet nuclei are quickly dispersed. However, if the infected person is quarantined in a closed small space and if the infected person has severe coughing and sneezing, there is a possibility of airborne transmission to a healthy individual, especially if the healthy individual stays in the same room for a longer time.
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