World Health Organization has always held that Covid-19 is not airborne.  We have always believed that it spreads only through respiratory droplets.  But if an open letter written by 239 scientists from 32 countries to the WHO is anything to go by, the virus spreads even through air.

"In their letter, the experts have outlined the evidence showing that smaller particles can infect people. The researchers plan to publish their letter in a scientific journal," reports New York Times.

"Frightening new clusters of infection increasingly confirm what many scientists have been saying for months: The coronavirus lingers in the air indoors, infecting those nearby," says the NYT report.

Just a few days ago, the WHO clearly said that airborne transmission of Covid-19 is possible "only after medical procedures that produce aerosols, or droplets smaller than 5 microns."

If what the scientists are saying is irrefutable, then we may have to start wearing masks even at homes, schools, cinema halls, etc.  Spaces with poor ventilation will be the most dangerous even if everyone there maintains social distancing.