The Production and Testing of Typhoid Fever Vaccine in Nigeria

Abstract

Sixty-six different types of vaccines were prepared using three adjuvants and using both local and imported strains of Salmonella typhi  and Salmonella paratyphi A, B, & C.  About 3,960 mice, 90 rabbits, 5 monkeys and hundreds of humans were vaccinated with 0.5 ml of vaccine and after 3 weeks of vaccination challenged (except humans) with 0.5ml of live culture of causative organisms.  Twenty six vaccines sufficiently protected the vaccinates.  The best eight of the 26 vaccines were used to vaccinate rabbits and after challenge 3 vaccines that had antibody tires of ¹/160 using Widal test were used for monkey testing.  All the 5 monkeys used were solidly protected against typhoid fever.  The vaccine used for the test in monkeys was also used for human testing. Human vaccinates reported some reactions at the site of inoculation.  The level of reaction varied from person to person.  A few people complained of feverish condition on the first day of vaccination.  Reports from the vaccinates and our own tests in the laboratory indicate that people are protected against the disease for up to 3 years.