The Association of Hepatitis B Vaccine Supply Policy with Timing of Receipt of the First Dose of Hepatitis B Vaccination

Abstract

An estimated 800,000 - 1.4 million persons in the US have chronic hepatitis B virus (HBV) infection. The risk for chronic infection is greatest among young children; approximately 90% of infants will remain chronically infected with HBV. Approximately 25% of those who become chronically infected during childhood die prematurely from cirrhosis or liver cancer. Hepatitis B vaccination is the most effective measure to prevent HBV infection and its consequences. In 2006, 29 US states had Hepatitis B Vaccine Supply (HBVS) policy which either supplies hepatitis B vaccine at no cost to all providers for all children or provides hepatitis B vaccine to delivery hospitals-only free of charge for all infants; other 21 US states and the District of Columbia did not have. 17,636 infants born in 2006 obtained from 2007-2009 National Immunization Survey (NIS) were analyzed with survival analysis procedures of Kaplan-Meier estimate and Cox proportional hazards model for complex sample survey to evaluate the association between state HBVS policy and the timing of infant age in days to receipt of hepatitis B vaccination. State HBVS policy is associated with infant age in days from birth to receipt of the first dose of hepatitis B vaccine (P < 0.01), and to completion of the 3-dose hepatitis B vaccine series (P < 0.01). Receipt of the first dose of hepatitis B vaccine occurred 31% earlier among infants residing in states with HBVS policy than among infants residing in states without (adjusted hazards ratio 1.31, 95%CI (1.23, 1.39)). Completion of the 3-dose hepatitis B vaccine series were 12% sooner among infants living in states with HBVS policy than among infants living in states without (adjusted hazards ratio 1.12, 95%CI (1.06, 1.18)). State HBVS policy may help overcome barriers to timely delivery of hepatitis B vaccines to infants.