CDC updates guidance for COVID-19 close contact exposure times

The Centers for Disease Control and Prevention is once again revisiting the guidelines it has issued when it comes to protecting yourself against contracting COVID-19.

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The CDC has adjusted the wording of its advisory concerning what it considers close contact.

Previously, the agency had said close contact consisted of being within six feet of an infected person for 15 minutes.

Now the CDC says that the 15-minute timeframe is cumulative.

That means that the 15 minutes could be in three five-minute increments over 24 hours. The contact doesn’t have to happen all at one time.

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“Cumulative exposures can be as hazardous as 15 sustained continuous minutes of exposure,” Dr. William Schaffner, an infectious disease expert, told NBC News.

The CDC also reminds the closer the distance, the higher the risk of exposure. This also applies to any actions that happen during the time period, for example singing, coughing or shouting.

Other environmental factors also affect exposure, including whether the interaction happened inside or outside, if there was a crowd and if there was adequate ventilation.

The revised guidance came after an outbreak in a Vermont prison, NBC News reported.

According to the CDC, six prisoners were processed at the jail and held in a quarantine unit. They were tested for COVID-19 and the results eventually ended up coming back positive. As the jail officials waited for results to come back, one correctional worker interacted with the prisoners, but the interactions were shorter than the 15-minute close contact parameters, so he continued working. Eventually, the corrections officer started showing signs of the coronavirus infection. Surveillance video showed that the officer did not spend 15 minutes with the prisoners at one time, but the interactions were a combined total of 17 minutes. The officer also had no travel or contact with people infected with COVID-19 outside of work.

The Washington Post reported that at least one of the detainees was asymptomatic.

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The CDC also said that the correctional officer may have been exposed to the airborne virus or from surface contact, the newspaper reported.

The new guidance could impact schools and workplaces, The Washington Post reported. It also demonstrates the importance of wearing a mask when interacting with others.

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