Fast Five Quiz: Key Aspects of Influenza

Michael Stuart Bronze, MD


March 31, 2020

Aerosol transmission may occur 1 day before the onset of symptoms; thus, it may be possible for transmission to occur via asymptomatic persons or persons with subclinical disease who may be unaware they have been exposed to the disease. The incubation period of influenza virus ranges from 1 to 4 days. Viral shedding occurs at the onset of symptoms or as much as 24-48 hours prior to the onset of illness. Shedding continues for 5-10 days. Young children may shed virus longer, placing others at risk for contracting infection. In highly immunocompromised persons, shedding may persist for weeks to months.

Transmission of influenza virus from poultry or pigs to humans appears to occur predominantly as a result of direct contact with infected animals. The risk is especially high during slaughter and preparation for consumption; eating properly cooked meat poses no risk.

Read more about influenza virus transmission and infection.


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