Filling and Drying

FILLING AND DRYING

As vaccine is required to meet orders, bulk vaccine is distributed into single-dose ampoules or into multidose vials as necessary. Vaccines that are filled as liquids are sealed and capped in their containers, whereas vaccines that are provided as dried preparations are freeze-dried before sealing.

The single-component bacterial vaccines are listed in Table 24.1. For each vaccine, notes are provided of the basic material from which the vaccine is made, the salient production processes and tests for potency and for safety. The multicomponent vaccines that are made by blending together two or more of the single-component vaccines are required to meet the potency and safety requirements for each of the single components that they contain. The best-known of the combined bacterial vaccines is the adsorbed diphtheria, tetanus and pertussis vaccine (DTPer/Vac/Ads) that is used to immunize infants, and the adsorbed diphtheria and tetanus vaccine (DT/Vac/Ads) that is used to reinforce the immunity of school entrants. The trend is to produce increasingly complex combinations, and hepta-and octavalent preparations are now available.

The single-component viral vaccines are listed in Table 24.2, with notes similar to those provided with the bacterial vaccines. The only combined viral vaccine that is widely used is the measles, mumps and rubella vaccine (MMR Vac). In a sense however, both the inactivated (Salk) poliovaccine (Pol/Vac (inactivated)) and the live (Sabin) poliovaccine (Pol/Vac (oral) are combined vaccines in that they are both mixtures of virus of each of the three serotypes of poliovirus. Influenza vaccines, too, are combined vaccines in that they usually contain components from several virus strains, usually from two strains of influenza A and one strain of influenza B.