WHO has long dismissed the possibility that the coronavirus is spread in the air except for certain risky medical procedures, such as when patients are first put on breathing machines. Airborne spread "particularly in specific indoor locations, such as crowded and inadequately ventilated spaces over a prolonged period of time with infected persons cannot be ruled out, WHO said. WHO's stance also recognized the importance of people spreading COVID-19 without symptoms, a phenomenon the organization has long downplayed. WHO has repeatedly said such transmission is rare" despite a growing consensus among scientists globally that asymptomatic spread likely accounts for a significant amount of transmission. ___The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institutes Department of Science Education.