Adolescents May Require Hepatitis B Vaccine Boosters
 Widespread
vaccination of infants and children against hepatitis
B has dramatically reduced the incidence of the disease, but it remains unclear
how long this protection lasts.
As reported in the May 15, 2008, Journal
of Infectious Diseases, researchers in Taiwan conducted a study to assess
whether vaccine-induced immunity persists into adulthood.
In 2004-2005,
a total of 6156 high school students (aged 15-21 years) who had been vaccinated
with plasma-derived hepatitis B vaccine as infants were recruited for HBV seromarker
screening.
Immune response to a hepatitis B vaccine booster was evaluated
in 872 participants who were seronegative. Hepatitis B surface antibody (anti-HBs)
titers and levels of peripheral blood mononuclear cells secreting hepatitis B
surface antigen (HBsAg)-specific interferon-gamma (IFN-gamma) or interleukin-5
(IL-5) were determined 4 weeks later.
Results
•
Although the vaccine remained highly efficacious in reducing the HBsAg positivity
rate, 63.0% of the vaccine recipients had no detectable protective anti-HBs antibodies.
•
After the booster, anti-HBs remained undetectable in 28.7% of participants who
had received a complete 4-dose hepatitis B vaccination series during infancy.
•
HBsAg-specific IFN-gamma or IL-5 secreting PBMCs were not detected in 27.2% of
the study participants.
•
The investigators estimated that 10.1% of the total population had lost their
vaccine-conferred response.
"A
notable proportion of fully vaccinated adolescents had lost immune memory conferred
by a plasma-derived hepatitis B vaccine 15-18 years later," the study authors
concluded. "This decay of immune memory may raise concerns about the need
for a booster vaccine for high-risk groups in the long run."
6/20/08 Reference
CY
Lu, YH Ni, BL Chang, and others. Humoral and cellular immune responses to a hepatitis
B vaccine booster 15-18 years after neonatal immunization. Journal of Infectious
Diseases 197(10): 1419-1426. May 15, 2008. |
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