A COMMITTEE of the Food and Drug Administration (FDA) has unanimously recommended that the agency approve a study that will deliberately infect human volunteers with live typhoid bacillus. The ultimate objective is to provide a means for identifying effective candidate typhoid vaccines for future testing in field trials—which will, presumably, involve a different group of volunteers.
The proposed study would also provide further knowledge of the pathogenesis and the immune response to wild type Salmonella typhi, and provide an opportunity to look into mechanisms of attenuation of the organism that might be useful for developing future vaccines. When actual candidate vaccines are tested, the studies will also provide an opportunity to demonstrate whether they protect persons who travel from nonendemic to typhoid-endemic areas.
Marwick C. Volunteers in Typhoid Infection Study Will Aid Future Vaccine Development. JAMA. 1998;279(18):1423-1424. doi:10.1001/jama.279.18.1423