The Centers for Disease Control and Prevention changed its definition of what it means to be in close contact with an infected person and therefore at risk of contracting the coronavirus. The agency made the update in its published guidance for coronavirus contact tracing on Wednesday.
The new guideline says close contact means being within 6 feet of an infected person for a total of 15 minutes or more over a 24-hour period. The previous guideline said a person was at risk after 15 minutes of exposure within 6 feet of an infected person. One school district in Montana interpreted that to mean that if students moved every 15 minutes, the risk of infection was mitigated.
The change could mean that when contact tracers speak to people who were close to an infected person, they could consider more of them at risk of also becoming infected.
In the guidance, the agency notes that it does not have much data on what actually constitutes “close contact.” But it added that a total of 15 minutes of exposure to an infected person “can be used as an operational definition for contact investigation.”
The C.D.C. added that the closer the contact, the greater the risk. Risk also increases over more time in contact with someone infected and from contact with an infected person who has symptoms. Someone who is coughing, singing or shouting is more likely to spread the virus, the C.D.C. said.
Source : Nytimes
