On October 21, the CDC updated its definition on what is considered “close contact” for exposure to someone who is infected with COVID-19. The CDC now defines close contact as someone who was within 6 feet of an infected person for a cumulative total of 15 minutes or more over a 24-hour period. This includes individual, brief exposures added together over a 24-hour period (for example, three 5-minute exposures for a total of 15 minutes).

Previously, the guidance only defined close contact as at least 15 continuous minutes within 6 feet. The update goes on to explain that the closer the distance and the longer the duration of potential contact, the greater the risk of contracting COVID-19. This applies regardless of whether masks or other PPE were being utilized by either party during the contact.

This update comes as a result of a Vermont prison worker contracting the virus after several brief interactions with COVID-19 positive inmates–none of them individually more than a minute or two, but adding up to just 17 minutes during a single shift.

A reminder that the relevant exposure period begins starting from 2 days before the infected person’s onset of symptoms (or, if asymptomatic, 2 days prior to the COVID-19 test) throughout the time the infected person should be isolating per CDC guidelines. The updated guidance also cautions that the period around onset of symptoms is associated with the highest levels of virus shedding, meaning that anyone who comes into contact with an infected person has the highest risk of contracting the virus during that time. Per the CDC, anyone who comes into close contact with a person infected with COVID-19 should quarantine and get tested for the virus.

The CDC also updated its guidelines on when to end isolation for those who have been infected with COVID-19 (and, for our purposes, when they may return to work). For most coronavirus-positive people, isolation can end 10 days after symptom onset if they are fever-free (without the use of fever-reducing medications) for at least 24 hours and if other symptoms have improved. Some individuals with severe coronavirus illness should extend isolation and precautions for up to 20 days after symptom onset.

For those who contract COVID-19 but never develop symptoms, isolation can end 10 days after the date of their first positive test. For most people (except those who are severely immunocompromised), a test-based strategy for determining when to discontinue isolation is no longer recommended.

In October, the CDC also updated its list of underlying medical conditions which place people at an increased risk for severe illness if they contract COVID-19, highlighting the impact of obesity, being overweight, and smoking (or a history of smoking). That updated guidance may be found here.

By Rebecca D. Bullard, rbullard@dsda.com