ABSTRACT
Immunogenicity of four plasma-derived hepatitis B vaccines (Merck, Sharp and Dohme, Pasteur, Dutch CLB and Korean Cheil-Sugar) was compared in Thai young adults. After primoimmunization, only the Merck and Pasteur vaccines could achieve greater than 90% seroconversion (i.e. anti-HBs greater than or equal to 10 mIU ml-1) whereas both the CLB and Korean vaccines needed a fourth dose to achieve this level of seroconversion. The anti-HBs titres of both heat-inactivated vaccines (CLB and Korean) were also significantly lower than those of the other two vaccines. We propose that the HBsAg content in both heat-inactivated vaccines should be increased and a booster (fourth) dose should be given in order to enhance their immunogenicities.
Subject(s)
Viral Hepatitis Vaccines/immunology , Adult , Drug Administration Schedule , Female , Hepatitis B Antibodies/biosynthesis , Hepatitis B Vaccines , Humans , Male , Thailand , Viral Hepatitis Vaccines/administration & dosage , Viral Hepatitis Vaccines/adverse effectsABSTRACT
The effect of combining tetanus toxoid in the same syringe with purified Vero cell rabies vaccine (PVRV) was investigated in the 2-1-1 regimen of PVRV. The 2-1-1 regimen alone was as immunogenic as the five-dose regimen, while saving one dose of vaccine and two clinic visits. When aluminium hydroxide-adsorbed tetanus toxoid was used to dissolve PVRV on days 0 (one of the two doses) and 21, the anti-rabies antibody was significantly increased. Aluminium-free tetanus toxoid was ineffective, suggesting that immunoenhancement was due to aluminium adjuvant. In addition, anti-tetanus antibody was unaffected and the side-effects were not increased by such mixing.
