GENEVA/CHICAGO—The World Health Organization (WHO) is reviewing a report urging it to update guidance on the novel coronavirus after more than 200 scientists, in a letter to the health agency, outlined evidence the virus can spread in tiny airborne particles.
The WHO says SARS-CoV-2, the virus that causes COVID-19, spreads primarily through small droplets expelled from the nose and mouth of an infected person that quickly sink to the ground.
