The Centers for Disease Control and Prevention has redefined what it considers “close contact” with someone who has COVID-19. The term refers to the amount of time one has to spend in the presence of a person with COVID-19 in order to contract the disease from them. And unfortunately, the concept of “close contact” has become even more restrictive.
Previously, the CDC described “close contact” as being within six feet of a COVID-19-infected individual for 15 minutes. In other words, if you were standing close to someone who had COVID-19 for at least 15 minutes there was a good chance you could become infected too.
However, now the CDC says that 15-minute time frame doesn’t need to be consecutive. Rather, now you are considered to have had “close contact” with an infected individual if you’ve spent a cumulative 15 minutes over a 24-hour period standing within six feet of them. In other words, if you spent five minutes near an infected individual at 8 a.m., four minutes with the same individual at noon, and six minutes with that individual at 7:30 p.m., you’re now considered to have had “close contact” and could have very well been infected yourself.
The CDC is changing its definition of close contact after a study revealed SARS-CoV-2, the virus that causes COVID-19, can be transmitted in much shorter amounts of time than previously thought. In the study, a correctional officer with the Vermont Department of Corrections came down with COVID-19 after having “multiple brief encounters” with incarcerated individuals:
Although the correctional officer never spent 15 consecutive minutes within 6 feet of an IDP [incarcerated or detained persons] with COVID-19, numerous brief (approximately 1-minute) encounters that cumulatively exceeded 15 minutes did occur. During his 8-hour shift on July 28, the correctional officer was within 6 feet of an infectious IDP an estimated 22 times while the cell door was open, for an estimated 17 total minutes of cumulative exposure.
Bottom line: These findings mean the CDC now believes it’s easier to pick up the SARS-CoV-2 virus than previously thought. Specifically, this could have massive implications for anyone who spends time in places where they are likely to have multiple interactions with the same people throughout the course of a day—such as offices, schools, and restaurants. An example of how it could affect people in restaurants is evident considering that a waiter might not be in the presence of specific diners for one 15-minute stretch of time, but could easily be in their presence for a cumulative 15 minutes. Under the new CDC guidance, that puts both the waiter and patrons in danger.
The new understanding of “close contact” also means that more people than previously thought should be self-quarantining after brief but repeated exposures to COVID-19-infected persons within a 24-hour period.