[Genetic factors in typhoid fever].

The study of genetic factors associated to infectious diseases is a promising research field for optimizing their management and control in the future. For typhoid fever, one of our major health problems, this approach has been sporadic an fruitless for having been addressed to disease's overall susceptibility. Moreover, difficulties on recognition of clinical sub-sets have prevented definition of unambiguous clinical phenotypes appropriate for this objective. With the aim of finding the basis for phenotypes identification, or definite disease expressions, a search including foreign and national literature was carried out for the 1960-88 period. From animal experimentation, human immunogenetics, epidemiology and clinical literature, data was obtained for proposing five phenotypes: the incubation period, typhoid relapse, agglutinins response (Widal's test), response to vaccination and metabolic behaviour of certain substances, including antibiotics. That one or more of these phenotypes and their possible association with polymorphic systems might lead to populational subsets recognition in typhoid fever is suggested.