| abstract |
An aqueous polyvalent vaccine comprises pertussis antigen, and a pharmaceutically acceptable water-soluble salt of 1,11-hexamethylene bis - [5 - (p - chlorophenyl)biguanide] (chlorhexidine) in a concentration in the range from 1:3000 to 1:500,000. Specified salts are the hydrochloride and acetate. The vaccine may increase poliomyelitis antigen, and diphtheria and tetanus toxoids. The chlorhexidine salt may be incorporated in the vaccine by addition at different stages in the production of the vaccine or in a single step. It may also be added separately to each of the aqueous components prior to pooling. Adjuvants, e.g. protamine sulphate, aluminium phosphate, may be added. |