Widal test: Diagnostic tool for typhoid and paratyphoid diseases

Typhoid is a severe, infectious and life-threatening disease. Typhoid disease mainly hit on children who are in school-going age. It is not very common in adults and older people. In developing countries, facilities for isolation and culture are often not available especially in smaller hospitals and diagnosis relies upon the clinical features of the disease and detection of agglutinating antibodies to Salmonella typhi and salmonella paratyphi by the Widal test. A total of 1461 blood samples received in the lab over a period of two years were tested by conventional rapid slide agglutination using commercially available antigens. In the present study the prevalence of seropositivity was 24.36%. With 59% of the samples from males and 41% from females and maximum positive cases were from males 13.27%. Most of the positive cases in the present study were from the age group of 05-10 years 39.01%. Amongst all antigen, O antigen was found to be maximum positive antigen i.e18.75%. The elevated levels may have been due to cross-reacting antigens or an anamnestic response. There are more than 40 cross-reacting antigens between S. typhi and other Enterobacteriaceae. The disease remains an important public health problem in developing countries. Proper sanitation, public health education and vaccination are the long term preventive measures to decrease or control the disease.