Evaluation of a newly developed ELISA against Widal, TUBEX-TF and Typhidot for typhoid fever surveillance

Introduction: Typhoid fever is endemic in many parts of the world and represents a major cause of acute febrile illness (AFI). Rapid and accurate laboratory methods for diagnosis of this disease are needed for both patient care and surveillance situations. Methodology: Serum samples were collecte...

Full description

Saved in:
Bibliographic Details
Main Authors: Moustafa Abdel Fadeel, Brent L House, Momtaz M Wasfy, John D Klena, Engy E Habashy, Mayar M Said, Mohamed Abdel Maksoud, Bassem Abdel Rahman, Guillermo Pimentel
Format: Article
Language:English
Published: The Journal of Infection in Developing Countries 2011-03-01
Series:Journal of Infection in Developing Countries
Subjects:
Online Access:https://jidc.org/index.php/journal/article/view/1339
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Introduction: Typhoid fever is endemic in many parts of the world and represents a major cause of acute febrile illness (AFI). Rapid and accurate laboratory methods for diagnosis of this disease are needed for both patient care and surveillance situations. Methodology: Serum samples were collected from AFI patients and used to evaluate the performance of a newly developed ELISA assay that uses a mixture of somatic and flagellar antigens to detect the total antibody response against Salmonella enterica subspecies enterica serovar Typhi (S. Typhi) infection. The levels of Ig isotype response (IgG, IgM and IgA) were also evaluated, and results were compared to those of TUBEX-TF and Typhidot commercial kits.  Results: Of 234 culture-confirmed typhoid patients, the total Ig ELISA diagnosed 93% compared to 71% using Widal test. This sensitivity level (93%) is higher than that observed for the individual Ig ELISAs (IgG 75%; IgM 79%; IgA 57%) and the commercial tests TUBEX-TF (75%), Typhidot IgM (63%) and Typhidot IgG (28%). An agreement of 78% was achieved between the total Ig ELISA and Widal test. The average specificity of the ELISA was 96%. Using ELISA, up to 200 samples can be tested per run with cost per test at US$0.20. Conclusions: The developed ELISA shows superior sensitivity and specificity, when compared to Widal, TUBEX-TF and Typhidot assays, is more cost effective and allows higher throughput. This method is highly recommended for active surveillance studies or outbreak investigations of typhoid fever.
ISSN:1972-2680