Epidemiology of respiratory syncytial virus infection requiring hospitalization in East Denmark

BACKGROUND: Prophylaxis against infection caused by respiratory syncytial virus (RSV) with high titered RSV immunoglobulin or humanized antibody may soon be available in Europe.

OBJECTIVE: To study the epidemiology of RSV infections requiring hospitalization in infants <6 months in East Denmark to provide a rational basis for decisions concerning prophylaxis against RSV.

METHOD: Populat ion-based retrospective review of case records of infants <6 months admitted to pediatric departments with RSV infection in East Denmark from November 1, 1995, to April 30, 1996.

RESULTS: Data were obtained from 459 infants. Seventy-three had predisposing conditions: prematurity, 49; pulmonary disease, 2; congenital heart disease, 7; neurologic disease, 6; others, 9. One preterm infant had bronchopulmonary dysplasia. The incidence of RSV infection requiring hospitalization in East Denmark among infants <6 months was estimated to be 34/1000/season. It was 32/1000/season among term infants and 66/ 1000/season among preterm infants (P<0.001). Infants with predisposing conditions and/or nosocomial infection (n = 24) had significantly more severe courses than otherwise healthy infants (P<0.01). One-hundred thirty infants received respiratory support by nasal continuous positive airway pressure, but only six required mechanical ventilation. No infants died.

CONCLUSION: The course of RSV disease in East Denmark was milder than reported elsewhere, possibly as a result of the low prevalence of bronchopulmonary dysplasia in Denmark. However, RSV constitutes a considerable burden to the Danish pediatric health care system, and therefore prophylaxis against RSV is desirable.