The Centers for Disease Control and Prevention ("CDC") recommends quarantine for those who have been in “close contact” to a person who tested positive for COVID-19. Local health departments (and employers) typically rely on the CDC guidance in performing contact tracing and notifying exposed individuals. Wednesday, October 21, the CDC broadened the definition of “close contact” from being within 6 feet of the person for 15 or more consecutive minutes to being in contact for 15 or more total minutes over a 24-hour period (for example, three 5-minute exposures for a total of 15 minutes). The 24-hour measuring period starts from 2 days before illness onset (or, for asymptomatic patients, 2 days prior to test specimen collection) until the time the patient is isolated.

The CDC goes on to explain that while “[d]ata are limited, making it difficult to precisely define “close contact;” 15 cumulative minutes of exposure at a distance of 6 feet or less can be used as an operational definition for contact investigation. Factors to consider when defining close contact include proximity (closer distance likely increases exposure risk), the duration of exposure (longer exposure time likely increases exposure risk), whether the infected individual has symptoms (the period around onset of symptoms is associated with the highest levels of viral shedding), if the infected person was likely to generate respiratory aerosols (e.g., was coughing, singing, shouting), and other environmental factors (crowding, adequacy of ventilation, whether exposure was indoors or outdoors)."

Employers who have existing policies describing “close contact” to specify continuous contact should consider revising their policies.