There has been a lot of confusion over the usage of facemasks against coronavirus. According to US-based Centre for Disease Control and Prevention (CDC) a person should wear a facemask if she or he is likely to be in close proximity to a person infected with the virus.
According to a New York Times report, Dr Robert Redfield, director of the CDC, confirmed in a radio interview earlier this week that the agency was reviewing its guidelines on who should wear masks. Citing new data that shows high rates of transmission from people who are infected but show no symptoms, he said the guidance on mask wearing was "being critically re-reviewed, to see if theres potential additional value for individuals that are infected or individuals that may be asymptomatically infected."
Here is what the world health body has to say on the usage of facemasks (respirators) as a protetive gear against coronavirus —

  • Most often, spread of respiratory viruses from person-to-person happens among close contacts (within 6 feet). Recent studies indicate that people who are infected but do not have symptoms likely also play a role in the spread of COVID-19.
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