To determine whether a difference in antibody to hepatitis B surface antigen (anti-HBs) response to a hepatitis B vaccine challenge dose existed among persons with a baseline anti-HBs level of 0 mIU/mL (group 1) and those with “non-zero” levels of 0.1–4.9 (group 2) and 5.0–9.9 (group 3) mIU/mL, according to the VITROS ECi anti-HBs assay.

Subanalysis of randomized clinical trial. Response was defined as a postchallenge anti-HBs level of at least 10 mIU/mL and 4-fold rise in anti-HBs level 2 weeks after a single challenge dose of 10 vs 20 µg Engerix-B. Baseline was defined as the anti-HBs level immediately before administration of the challenge dose.

Pediatric integrated healthcare system near Houston, Texas.

Three hundred nineteen US-born 16–19-year-olds who completed the hepatitis B vaccine series during the first year of life.

One hundred seventy-eight persons had zero (group 1) and 141 (114 group 2 and 27 group 3) had non-zero anti-HBs levels at baseline. Response to the challenge dose was significantly higher among those with non-zero vs zero anti-HBs levels, irrespective of challenge dosage; only 1 person with a non-zero anti-HBs level failed to respond to the challenge dose (group 3, 27/27 [100%] vs group 2, 113/114 [99%] vs group 1, 145/178 [82%]; P<.0001).

Among participants with residual anti-HBs levels less than 10 mIU/mL 16–19 years after primary hepatitis B vaccination during infancy, non-zero anti-HBs levels, with rare exception, indicated persistence of immune memory to HBsAg.

ClinicalTrials.gov Identifier: NCT01341275

Infect Control Hosp Epidemiol 2015;00(0):1–5

To evaluate hepatitis B vaccination coverage and documentation of vaccine-induced immunity.

Retrospective cohort analysis.

Graduate school in the United States with programs in osteopathic medicine, dentistry, and allied health.

Data collected included demographics, dates of hepatitis B vaccine doses, and postvaccination concentrations of antibody to hepatitis B surface antigen (anti-HBs), with dates. The proportions of students with anti-HBs of 10 IU/L or more by demographics, age at vaccination, interval since completion of the primary series, and response to additional vaccine doses were compared.

Of 3,452 students who matriculated during 2004–2009, 2,643 had complete data; 2,481 (93.9%) received 3 primary doses. Most were women (64.6%), US-born (85.6%), and white (63.2%); median age at receipt of the primary series was 14.5 years (interquartile range, 11.6–20.2 years) and at postvaccination testing was 23.2 years (interquartile range, 22.1–24.8 years). Of those who received 3 primary doses, 2,306 (92.9%) had an anti-HBs postvaccination concentration of 10 IU/L or more. Younger age at vaccination and longer time interval from vaccination to anti-HBs testing were associated with a postvaccination concentration of less than 10 IU/L (P < .001 and P = .0185, respectively, Cochran-Armitage test for trend). Almost all students (98.2%) who initially had less than 10 IU/L of anti-HBs, but then received at least 1 additional dose, had a follow-up anti-HBs concentration of 10 IU/L or more.

Almost all students had serologic evidence of protection against hepatitis B virus infection; most were vaccinated as adolescents and were tested more than 10 years after vaccination. Among students with anti-HBs concentrations of less than 10 IU/L, nearly all had 10 IU/L or more after at least 1 additional vaccine dose.