Influenza

Influenza is a viral syndrome caused by a highly contagious viral infection. It presents with acute fever, respiratory symptoms, rigors, malaise, myalgia, and/or fatigue. Substantial morbidity and mortality can result in susceptible populations, including patients who are at the extremes of age; have chronic medical conditions; or are immunocompromised, pregnant, reside in a nursing home, obese, or of Native American descent. Antiviral treatment is recommended for those requiring hospital admission, those with lower respiratory tract disease, and inpatient populations at high risk for complications. In addition to causing a viral pneumonia, influenza damages the respiratory epithelium. This increases the risk of bacterial coinfection, especially in those with severe illness, pneumonia, and otitis media. Preventive recommendations include vaccination for everyone over the age of 6 months, minimizing potential exposures, attention to respiratory and hand hygiene, adherence to standard precautions, and minimizing visitors for patients in isolation for influenza.