Vaccines Provide Hep B Immunity in Children for at Least 5 Years

Booster doses appear unnecessary for infants who receive hexavac or infanrix hexa
By Beth Gilbert
HealthDay Reporter

WEDNESDAY, Sept. 29 (HealthDay News) -- Infants vaccinated with hexavalent vaccines, including hexavac, appear to maintain immunity to hepatitis B for at least five years after primary vaccination, suggesting that booster doses are not necessary to maintain immunity, according to a study published online Sept. 29 in The Lancet Infectious Diseases.

Alessandro Remo Zanetti, Ph.D., of the University of Milan in Italy, and colleagues measured antibody concentrations five years after immunization of infants with hexavac or infanrix hexa. Children with concentrations of antibodies to hepatitis B surface antigen (anti-HBs) below 10 mIU/mL were randomized to receive a booster of HBVaxPro or engerix B monovalent hepatitis B vaccine and tested two weeks later.

The investigators found that 38.4 percent of the children who received hexavac had anti-HBs concentrations of 10 mIU/mL or more, versus 83.2 percent of those who received infanrix hexa. Geometric mean concentrations (GMCs) prior to the booster were 4.5 mIU/mL in the hexavac group and 61.3 mIU/mL in the infanrix hexa group. After the booster, 92.1 percent of children primed with hexavac and 94.3 percent primed with infanrix hexa had anti-HBs concentrations of 10 mIU/mL or more (P = 0.4), with GMCs equal to 448.7 mIU/mL and 484.9 mIU/mL, respectively (P = 0.6).

"At present, routine booster doses of hepatitis B vaccine do not seem necessary to sustain immunity in children vaccinated with hexavalent vaccines, including those immunized with hexavac," the authors write.

Three authors disclosed financial ties to GlaxoSmithKline, Sanofi Pasteur MSD, and/or Wyeth.

Full Text (subscription or payment may be required)

Copyright © 2010 HealthDay. All rights reserved.

Powered by