Prevalence is defined as the number of cases of a given disease in a specified population at a designated time per 100,000 people. Typhoid and paratyphoid are acute bacterial infections that most commonly cause febrile illness and gastrointestinal symptoms. Severe cases are associated with intestinal bleeding and perforation, altered mental state and, in some cases, death. We define a confirmed case as one for which there has been a positive blood culture test for either Salmonella enterica typhi or paratyphi. Diagnostic criteria do not typically accompany national surveillance reports; however, with blood culture being the standard diagnostic, we treat reported cases as confirmed. Given the poor sensitivity of blood culture, however, we estimated case definition as simply febrile illness resulting from an infection with Salmonella enterica typhi or paratyphi.
Source: Global Health Data Exchange