In update, CDC says SARS-CoV-2 ‘can sometimes be spread’ via airborne transmission
The CDC updated its online COVID-19 guidance to say that SARS-CoV-2 “can sometimes be spread by airborne transmission.”
The note was added 2 weeks after the CDC added and then subsequently removed information from the website regarding airborne spread of the virus, saying that the update had been posted by mistake and was still under review.
“CDC continues to believe, based on current science, that people are more likely to become infected the longer and closer they are to a person with COVID-19,” the agency said in a statement emailed to media outlets. “Today’s update acknowledges the existence of some published reports showing limited, uncommon circumstances where people with COVID-19 infected others who were more than 6 feet away or shortly after the COVID-19-positive person left an area.”
The current guidance, which can be found here, includes the following information:
- Some infections may spread via small droplets and particles that can linger in the air for minutes or hours;
- This spread is known as airborne transmission and affects transmission of infections including measles and tuberculosis;
- Some evidence suggests COVID-19 patients have infected others standing more than 6 feet away, and these transmissions were more common in enclosed spaces with poor ventilation;
- Scientists hypothesize that the amount of small droplets and particles created by COVID-19 patients became concentrated enough to spread the virus, and those infected were in the same location during or shortly after the COVID-19 patient that infected them had left;
- Current data suggest it is significantly more common for COVID-19 to spread via close contact with infected individuals than airborne transmission.
The potential of SARS-CoV-2 to be spread via airborne transmission has been a topic of debate for months. The CDC did not change any recommendations based on the updated guidance.
“People can protect themselves from the virus that causes COVID-19 by staying at least 6 feet away from others, wearing a mask that covers their nose and mouth, washing their hands frequently, cleaning touched surfaces often and staying home when sick,” it said.