Recent trends in severe respiratory syncytial virus (RSV) among US infants, 1997 to 2000.

OBJECTIVES: To provide current estimates of the incidence, associated risk factors, and costs of severe respiratory syncytial virus (RSV) infections among infants in the United States, defined as emergency department (ED) visits, hospitalization, and death. STUDY DESIGN: Retrospective analysis of National Hospital Ambulatory Medical Care Survey data 1997 to 2000; National Hospital Discharge Survey data 1997 to 2000; Perinatal Mortality Linked Files 1998 to 1999. The Hospital Cost Utilization Inpatient Sample data 1997 to 2000 were used to estimate hospitalization costs, and the 2001 Medicare fee schedule was used to estimate ED visit costs. Census data were used for population estimates. Between 1997 and 2000, there were 718,008 ED visits by infants with lower respiratory infection diagnoses during the RSV season (22.8/1000), and 29% were admitted. Costs of ED visits were approximately 202 million US dollars. RSV bronchiolitis was the leading cause of infant hospitalization annually. Total hospital charges for RSV-coded primary diagnoses during the 4 years were more than 2.6 billion US dollars. An estimated 390 RSV-associated postneonatal deaths occurred in 1999. Low birth weight and prematurity significantly increased RSV-associated mortality rates. CONCLUSIONS: RSV is a major cause of infant morbidity and mortality. Severe RSV is highest among infants of black mothers and Medicaid-insured infants. Prematurity and low birth weight significantly increase RSV mortality rates.

Respiratory syncytial virus-coded pediatric hospitalizations, 1997 to 1999.

BACKGROUND: The recent number and rate of infant hospitalizations with a respiratory syncytial virus (RSV)-coded diagnosis have not been published. METHODS: Retrospective data analysis. National Hospital Discharge Survey data for 1997 to 1999 were analyzed for discharges of infants < 1 year old with an RSV-coded diagnosis (ICD-9-CM 466.11, 480.1, 079.6). Hospitalization rates were estimated with annual midyear Census data. RESULTS: RSV bronchiolitis was the leading primary diagnosis annually for all infants hospitalized for any reason. Between 1997 and 1999, 297 684 RSV-coded discharges of infants with an RSV-coded diagnosis occurred. The associated hospitalization rate was 25.2 per 1000 infants. RSV-coded discharges peaked in February. CONCLUSION: RSV bronchiolitis was the leading cause of hospital admissions of infants younger than age 1 year for any reason between 1997 and 1999.

Hospitalization experiences of U.S. servicemembers before, during, and after participation in peacekeeping operations in Bosnia-Herzegovina.

BACKGROUND: There are relationships among morbidity experiences before, during, and after participation in overseas military operations. METHODS: U.S. servicemembers who deployed to Bosnia-Herzegovina during a 4-year period were classified based on their last hospitalizations prior to deploying. Hospitalization rates during and following deployment were calculated in relation to the timing and causes of pre-deployment hospitalizations. RESULTS: Deployers ever hospitalized pre-deployment were 120% and 50% more likely to be hospitalized during and following deployment, respectively. For nearly every category of diagnoses, hospitalization rates during and following deployment were highest among those hospitalized for the same category, intermediate among those hospitalized for other categories, and lowest among those not hospitalized prior to deploying. Deployers hospitalized within 1 month, 2-3 months, or > 3 months of deploying were 3.8, 2.6, and 1.4-times more likely to be hospitalized during deployment. CONCLUSIONS: The nature and recency of prior hospitalizations significantly determine during and post-deployment hospitalization risks.