title: Optimizing typhoid fever case definitions by combining serological tests in a large population study in Hechi City, China.
abstract: Blood culture-based diagnosis can only detect a fraction of the total burden of Salmonella enterica subsp. enterica serovar Typhi. The objective of the study was to detect additional typhoid fever cases through serological tests. A total of 1732 prolonged fever episodes were evaluated using three serological tests, Widal, Tubex and Typhidot-M in a typhoid fever endemic area of southern China. A case definition which included a positive Widal test (TO>or=80 & TH>A), a positive Tubex test (>or=4) and a positive Typhidot-M test, increased the detection of cases by more than twofold from 13 to 28 cases. The case definition has a specificity of 100% and a sensitivity of 39%. Case definitions based on combinations of serological tests can detect additional typhoid fever cases with higher specificity than a single serological test. Improved case detection is essential to understand the true disease burden and can help to boost the power of intervention trials.
authors.affiliation: Guangxi Center for Disease Prevention and Control, Nanning, Guangxi, China.
authors.forename: B
authors.initials: B
authors.lastname: Dong
authors.forename: C M
authors.initials: CM
authors.lastname: Galindo
authors.forename: E
authors.initials: E
authors.lastname: Shin
authors.forename: C J
authors.initials: CJ
authors.lastname: Acosta
authors.forename: A L
authors.initials: AL
authors.lastname: Page
authors.forename: M
authors.initials: M
authors.lastname: Wang
authors.forename: D
authors.initials: D
authors.lastname: Kim
authors.forename: R L
authors.initials: RL
authors.lastname: Ochiai
authors.forename: J
authors.initials: J
authors.lastname: Park
authors.forename: M
authors.initials: M
authors.lastname: Ali
authors.forename: L V
authors.initials: LV
authors.lastname: Seidlein
authors.forename: Z
authors.initials: Z
authors.lastname: Xu
authors.forename: J
authors.initials: J
authors.lastname: Yang
authors.forename: J D
authors.initials: JD
authors.lastname: Clemens
mesh_terms: D000293:Adolescent; D000328:Adult; D000372:Agglutination Tests / Q000379:methods; D002648:Child; D002675:Child, Preschool; D002681:China; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D006801:Humans; D008875:Middle Aged; D012680:Sensitivity and Specificity; D014435:Typhoid Fever / Q000175:diagnosis*