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Seasonal influenza in children: Clinical features and diagnosis

Flor M Munoz, MD, MSc
Section Editors
George B Mallory, MD
Morven S Edwards, MD
Deputy Editor
Mary M Torchia, MD


Influenza is an acute respiratory illness caused by influenza A or B viruses. It occurs in annual outbreaks, mainly during the winter season (in temperate climates). Signs and symptoms of upper and/or lower respiratory tract involvement are common, but the presentation varies with age and previous experience with influenza virus.

Certain groups of children are at increased risk of severe or complicated influenza infection (table 1). Although influenza generally is an acute, self-limited, and usually uncomplicated disease in healthy children, it can be associated with severe morbidity and mortality.

The clinical features and diagnosis of influenza in children will be reviewed here. The treatment and prevention of influenza in children, and influenza in adults, are discussed separately.

(See "Epidemiology of influenza".)

(See "Seasonal influenza in children: Prevention with vaccines".)


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