Cell mediated and humoral immune responses in human typhoid fever.

: The leucocyte migration inhibition test (LMIT) and the Widal test have been used to investigate the cell mediated (CMIR) and humoral immune responses (HIR) in 43 typhoid patients in comparison with the responses in 83 control subjects in two groups (65 normal persons and 18 sewerage workers) who were occupationally exposed to human faeces. The patients and the sewerage workers showed significantly higher CMIR than the normal persons. The O, H, and Vi antibody titres were significantly higher in the patients than in both control groups. Neither the CMIR nor the antibody titres differed significantly between the adult and paediatric patients. While we confirm that a CMIR does develop in typhoid patients, we found no correlation between the CMIR and the occurrence of complications. Neither the duration of the illness (after the first week) nor chloramphenicol therapy affected the CMIR or the HIR.