differential immunogenicity of a recombinant hepatitis b vaccine in iranian neonates: influence of ethnicity and environmental factors

objective: to compare immunogenicity of a recombinant hepatitis b (hb) vaccine in two groups of neonates born in two cities of iran with different geographic and ethnic backgrounds.   materials and methods: ten micrograms of a recombinant hb vaccine was administered under field condition to iranian healthy neonates at 0, 1.5 and 9 months intervals. the subjects consisted of two groups of 290 and 231 neonates selected from two cities located at north-west (urmia) and south-east (kerman) of iran, respectively. the level of anti-hbs antibody was quantitated in serum 2-4 weeks after administration of the last vaccine dose, by sandwich elisa.   results: a higher seroprotection rate (anti-hbs> 10 iu/l) (98.3% vs. 96.1%) and significantly increased serum anti- hbs antibody titer (11869 vs. 6104 iu/l) (p