1738Estimated Annual Perinatal Hepatitis B Virus Infections, 2000-2009

Background. Ninety-percent of perinatal hepatitis B virus (HBV) infection results in chronic HBV which usually is asymptomatic, but carries a 25% risk of premature death from progressive liver injury, cirrhosis, and liver cancer. In 1990, the Centers for Disease Control and Prevention (CDC) funded the Perinatal Hepatitis B Prevention Program (PHBPP) to accelerate elimination of perinatal HBV transmission in the United States. The annual rate of perinatal chronic HBV (CHBV) infections reported by PHBPP (0.8%-2.4%) was consistently lower than the annual rate estimated in CDC models employed from 2000-2009, suggesting not all cases in infants were identified. To better understand the factors with greatest impact on the estimated number of cases, we applied updated inputs to the current CDC model and performed sensitivity analyses for best and worst case scenarios. Methods. Models employed estimates of annual births to hepatitis B surface antigen (HBsAg)-positive women, data from PHBPP, and National Immunization Surveys (NIS) hepatitis B (HepB) vaccine coverage. Prenatal maternal HBsAg screening rates, the efficacy of post-exposure prophylaxis (PEP) consisting of HepB vaccine and hepatitis B immune globulin, and perinatal HBV transmission rates were from published literature. Results. The modeled estimate of the number of perinatal CHBV infections in 2009 was 952, equivalent to a baseline infection rate of 3.84%. Best and worst case sensitivity analysis yielded perinatal CHBV infection rates of 0.60% and 15.41%. One-way sensitivity analysis identified three major drivers: the proportion of infants receiving timely PEP, efficacy of PEP, and the perinatal HBV transmission rate. Three-way sensitivity analysis yielded perinatal CHBV infection rates of 0.70% and 13.64%. Conclusion. Modeling suggests a substantial number of perinatal HBV infections that occurred in 2009 in the United States were not identified by PHBPP. Limitations of the data contributed to discrepancies between the estimated and reported number of cases, but remain useful programmatic goals of achieving elimination of perinatal CHBV infection. Disclosures. All authors: No reported disclosures.