ABSTRACT
Typhoid fever is exceedingly uncommon in modern industrialized countries where populations are served by treated, bacteriologically monitored water supplies and by sanitation that removes human fecal waste. In contrast, in less-developed countries where populations commonly lack such amenities, typhoid fever is often endemic and, from the public health perspective, typically constitutes the most important enteric disease problem of school-age children [1]. Systematic clinical, epidemiological, and bacteriological surveillance for typhoid fever carried out in relation to field trials of the efficacy of candidate vaccines has provided more precise data on the incidence of typhoid in many populations [2-9]. The incidence rates recorded were much higher than predicted based on nonsystematic surveillance. Systematic household and health center-based surveys have also demonstrated a surprisingly high frequency of bacteremic (but in general clinically mild) typhoid infection among febrile infants and toddlers in endemic areas [10,11].
