Bronchiolitis-associated hospitalizations among American Indian and AlaskaNative children

Background. Respiratory syncytial virus (RSV) is the leading cause of lower respiratory tract illness among infants and young children, Respiratory sy stem diseases account for a large proportion of hospitalizations in America n Indian and Alaska Native (AI/AN) children; however, aggregate estimates o f RSV-associated hospitalizations among AI/AN children have not been made. Methods. We used Indian Health Service hospitalization data from 1990 throu gh 1995 to describe hospitalizations associated with bronchiolitis, the mos t characteristic clinical manifestation of RSV infection, among AI/AN child ren <5 years old. Results. The overall bronchiolitis-associated hospitalization rate among AI /AN infants <1 year old was considerably higher (61.8 per 1000) than the 19 95 estimated bronchiolitis hospitalization rate among all US infants (34.2 per 1000). Hospitalization rates were higher among male infants (72.2 per 1 000) than among females infants (51.1 per 1000). The highest infant hospita lization rate was noted in the Navajo Area (96.3 per 1000). Hospitalization s peaked annually in January or February, consistent with national peaks fo r RSV detection. Bronchiolitis hospitalizations accounted for an increasing proportion of hospitalizations for lower respiratory tract illnesses. Conclusions. Bronchiolitis-associated hospitalization rates are substantial ly greater for AI/AN infants than those for all US infants. This difference may reflect an increased likelihood of severe RSV-associated disease or a decreased threshold for hospitalization among AI/AN infants with bronchioli tis compared with all US infants. AI/AN children would receive considerable benefit from lower respiratory tract illness prevention programs, includin g an RSV vaccine, if and when one becomes available.