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Updated: Jul 17, 2026
An Allelotyping PCR for Identifying Salmonella enterica serovars Enteritidis, Hadar, Heidelberg, and Typhimurium
Published on: July 22, 2011
Early detection of typhoid by polymerase chain reaction
A Haque1, J Ahmed, J A Qureshi
1National Institute for Biotechnology and Genetic Engineering (NIBGE), and Department of Pathology, Punjab Medical College, Faisalabad, Pakistan.
Background:
Typhoid is a common problem in developing countries. Cultivation of bacteria and serology (especially Widal test) give unacceptable levels of false-negative and false-positive results, respectively.
Patients And Methods:
In this study, a recently introduced polymerase chain reaction-based technique (which has 100% specificity for Salmonella typhi) was compared with blood culture and Widal test during the first week of illness of 82 suspected cases of typhoid.
Results:
The respective figures of positivity for PCR, blood culture and Widal test were 71.95%, 34.1%, and 36.5%. A control group of 20 healthy persons gave figures of 0%, 0%, and 33.3%, respectively.
Conclusion:
We conclude that this PCR-based technique is not only absolutely specific, but also very sensitive and, therefore, much superior to blood culture and Widal test for the early diagnosis of typhoid.
