Controlled field trials and laboratory studies on the effectiveness of typhoid vaccines in Poland, 1961-64: Final report

Polish Typhoid Committee

Abstract

In recent years studies of the effectiveness of different typhoid vaccines have been sponsored by the World Health Organization in British Guiana, the USSR, and Yugoslavia. A similarly sponsored study has been made in Poland under the auspices of the Polish Typhoid Committee. In the controlled field trial four types of vaccine were used: (1) bacterial acetone-killed and -dried (vaccines K and P), (2) bacterial formol-killed phenol-preserved (vaccine N), (3) Westphal's endotoxin adsorbed on aluminium hydroxide (vaccine S), and (4) Grasset's vaccine (autolysate of typhoid bacilli adsorbed on aluminium hydroxide; vaccine T). The control vaccine was tetanus toxoid (vaccine O). Laboratory tests were also carried out.

In children aged 5-14 years who received two inoculations, vaccine N was the most effective, followed by K; vaccine T was distinctly less effective. In people aged 15-60 years the small number of typhoid cases made evaluation difficult; however, vaccines N and P inoculated once afforded protection, whereas vaccine S imparted none.

Further studies are desirable on the laboratory testing of typhoid vaccines: at present the H and O agglutination tests with sera of immunized rabbits, combined with an active mouse-protection test, can be recommended, provided that a standard typhoid vaccine is used for comparison.