Influenza virus is a major cause of respiratory infection in children. A specific and rapid diagnosis is important to determine the proper therapy, minimize the unnecessary use of antibiotics and provide for appropriate measures to prevent the spread of infection. Rapid diagnostic tests for influenza A virus are available and may be useful in the management of pulmonary infection with this pathogen.

Noyola and Demmler identified pediatric patients in whom an enzyme-linked immunoassay (EIA) test for the detection of influenza A virus was performed in a single virology laboratory. The case group consisted of all patients who were evaluated in the emergency department with respiratory symptoms and who were tested for influenza A virus. The median age of the case group was one year. The utility of the rapid diagnostic test was demonstrated in three ways: (1) patients with a positive influenza A EIA were less likely to receive antibiotics when discharged home from the emergency department than those with a negative test, (2) the duration of antibiotic use in hospitalized patients was significantly shorter in those in whom the diagnosis of influenza A had been established and (3) patients with a positive EIA were more likely to be given antiviral therapy. The availability of amantadine and rimantadine, as well as the neuraminidase inhibitors zanamivir and oseltamivir, have made early diagnosis of viral infections more useful.

The authors conclude that early diagnosis of a viral infection is useful in containing the indiscriminate use of antibiotics in pediatric patients with pulmonary symptoms in whom there is no obvious bacterial focus of infection.