Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2007 Aug;135(6):1014-20.
doi: 10.1017/S0950268806007801. Epub 2007 Jan 12.

Optimizing typhoid fever case definitions by combining serological tests in a large population study in Hechi City, China

B Dong  1 , C M Galindo, E Shin, C J Acosta, A L Page, M Wang, D Kim, R L Ochiai, J Park, M Ali, L V Seidlein, Z Xu, J Yang, J D Clemens
Affiliations

Optimizing typhoid fever case definitions by combining serological tests in a large population study in Hechi City, China

B Dong et al. Epidemiol Infect. 2007 Aug.

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.

PubMed Disclaimer

Figures

Fig. 1
Fig. 1
Assembling a study population for the case definition.
Fig. 2
Fig. 2
Sensitivity, specificity and yield of the selected case definition, in all episodes (n=1732) (TH⩾80 & TH>A, Tx⩾4, Td=positive). Wi, Widal test; Tx, Tubex®; Td, Typhidot-M®. A greater than twofold increase in number of cases from 13 culture-confirmed cases to 28 cases by combined serologies.
See this image and copyright information in PMC

References

    1. Bhutta ZA, Mansurali N. Rapid serologic diagnosis of pediatric typhoid fever in an endemic area: a prospective comparative evaluation of two dot-enzyme immunoassays and the Widal test. American Journal of Tropical Medicine and Hygiene. 1999;61:654–657. - PubMed
    1. Bopp CA, Murray PR Escherichia, Shigella and Salmonella. 8th edn Washington, DC: ASM Press; 2003. Manual of clinical microbiology; pp. 654–671. , pp.
    1. Cherian T et al. Prevalence of Salmonella typhi O and H antibodies in the serum of infants and preschool children. Indian Pediatrics. 1990;27:293–294. - PubMed
    1. Chongsa-nguan M et al. Current status of widal test in diagnosis of typhoid fever in an endemic area. Southeast Asian Journal of Tropical Medicine and Public Health. 1989;20:493–495. - PubMed
    1. Clegg A et al. Re-evaluation of the Widal agglutination test in response to the changing pattern of typhoid fever in the highlands of Papua New Guinea. Acta Tropica. 1994;57:255–263. - PubMed

Publication types