CDC: Evidence supports SARS-CoV-2 transmission while presymptomatic or asymptomatic

SARS-CoV-2 may spread from individuals who are presymptomatic or asymptomatic, according to a new Centers for Disease Control and Prevention report based on epidemiologic, virologic and modeling studies before CDC recommended widespread use of face masks.

The authors said the findings imply that the case-fatality rate may be lower than currently estimated, and reinforce the value of community interventions to stop the spread of the virus in the absence of symptoms.

“Critical knowledge gaps include the relative incidence of asymptomatic and symptomatic SARS-CoV-2 infection, the public health interventions that prevent asymptomatic transmission, and the question of whether asymptomatic SARS-CoV-2 infection confers protective immunity,” they said.