Ninety percent of patients in a 1981 hepatitis B vaccine trial still had evidence of immune protection 30 years later, according to a study in the Journal of Infectious Diseases.
The duration of protection after vaccination with hepatitis B virus vaccine is not well understood, although HBV vaccines have been effective at preventing infection, said authors of a new study led by Dr. Michael Bruce of the division of preparedness and emerging infections at the Centers for Disease Control and Prevention. To better assess the duration of protection offered by the plasma-derived hepatitis B vaccine, investigators performed a follow-up study of 1,578 Alaska Native adults and children aged at least 6 months who had been vaccinated in 1981 with three doses of the HBV vaccine.
©Amanda Mills/CDC
Dr. Bruce and his colleagues recruited 243 members of the original cohort who responded to the original primary vaccine series but received no subsequent doses during the 30-year period. The researchers tested cohort members for antibody to hepatitis B surface antigen (anti-HBs) levels. Those with levels less than 10 mIU/mL received one booster dose of recombinant hepatitis B vaccine 2-4 weeks later and were then evaluated on the basis of anti-HBs measurements 30 days after the booster.
Of the patients tested, 125 (51%) had anti-HBs levels greater than or equal to 10 mIU/mL. Among participants with anti-HBs levels below 10 mIU/mL who were available for follow-up, 75 of 85 (88%) responded to a booster dose with an anti-HBs level greater than or equal to 10 mIU/mL at 30 days.
Dr. Bruce and his colleagues concluded that, based on anti-HBs level greater than or equal to 10 mIU/mL at 30 years and an 88% booster dose response, at least 90% of participants had evidence of protection 30 years later, and thus HBV vaccine booster doses are not needed for persons 30 years out from a primary HBV vaccine series.
Read the full study in the Journal of Infectious Diseases (J Infect Dis. 2016 Jan 21. doi: 10.1093/infdis/jiv748).
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