ABSTRACT
The Department of Medical Research (DMR) has been producing a safe and effective plasma derived hepatitis B (HB) vaccine since 1997 to meet the criteria of quality control tests recommended by the WHO. The production of this HBvaccine requires the HBs antigen (Ag) pasitive blood as raw material which has been collected from blood banks of the various hospitals in Yangon area. Among these collected blood bottles, only those with high HBsAg titre were pooled and purified for further manufacturing process. In this study, HBsAg titre of the blood bottles collected during the year 1992, 1993,1999 and 2000, and those used for production of various batches of HB vaccine were determined and compared. It was found that the quantities of blood bottles available for HB vaccine production and their HBsAg titres have been apparently reduced in the last two years. This may affect the production capacity of the vaccine. This could be one of the major obstacles ofr the large scale production of the plasma-derived HB vaccine tho meet the requirement of Extended Program of Immumization (EPI) in the near future. To fulfil this requirement, several solutions have been considered and discussed in this study.