Hepatitis B Vaccine Seroprotection Among US Graduate Health-Science Students

Background:  Hepatitis B virus (HBV) infection is a major public health problem preventable by a highly effective vaccine.  The duration of protection after childhood hepatitis B vaccination among persons in the United States who later, as adults, are at occupational risk of exposure to HBV has not been documented.  

Objectives:  To assess seroprotection (antibody to hepatitis B surface antigen [anti-HBs] ≥10 mIU/mL) afforded by hepatitis B vaccine among students entering a US graduate school of the health sciences.

Methods:  We reviewed vaccination records from the student health clinic of students who: 1) matriculated from 2004-2009, and 2) had documented dates of receipt of hepatitis B vaccine and of postvaccination anti-HBs concentrations.

Results:  Among 2896 records reviewed, 2693 (93%) students completed the 3-dose primary series. Of those who received at least one dose, 2457 (85.0%) had anti HBs ≥ 10 IU/ml. Median age at first dose among these students was 14.7 years [0-54.3 years] with 2.0% having received the first dose at age ≤ 5 years. Median age at first anti-HBs titer determination was 23.3 years [10.7-53.8 years]. For 2693 students who completed the series, 2462 (91.4%) had a postvaccination test result, of whom 2299 (93.4%) had anti-HBs ≥ 10 mIU/mL. For the remaining 163 (6.6%) students with anti-HBs < 10 mIU/mL, 31 exclusively received a single “booster” dose, and of these, 24 (77.4%) had postvaccination testing with subsequent post-booster anti-HBs ≥10 IU/ml.

Conclusions:  Among incoming students in recent years, seroprotection from hepatitis B vaccine was high. Few students received the vaccine as infants or young children; most vaccination occurred during mid-adolescence.  Among students with postvaccination anti-HBs <10 mIU/mL, most responded to a single booster dose.