|
Antibody levels in Ethiopian children five years after vaccination with two different doses of hepatitis B vaccine: Is there a need for booster vaccine?
E Tsega | J Horton | E Nordenfelt | BJ Hansson | et al
It
was hypothesized that, following effective initial vaccination,
a booster dose of hepatitis B vaccine will not be necessary
in areas of hyperendemicity for hepatitis B virus (HBV)
infection. A total of 314 Ethiopian children, ranging
from two to 14 years old, were alternatively vaccinated
with 10 and 20 µg hepatitis B vaccine doses, using the
initial, one- and six-month schedule. Five years later,
210 of the vaccinees were retested for anti-HBV surface
antibody titres. Both 10 and 20 µg doses of hepatitis
B rDNA yeast vaccine were equally immunogenic and protective
against HBV infection for at least five years despite
marked reduction of mean antibody levels and geometric
mean titres, with 11% of the vaccinees showing antibodies
below the protective level. For firm further recommendations
a longer follow-up period of vaccinees is suggested.
|