The Widal test in the diagnosis of typhoid fever in the transvaal.

We analysed the results of the Widal test in the northern and eastern Transvaal in relation to bacteriologically confirmed cases of typhoid fever, patients suspected of having the disease, febrile patients without typhoid fever and healthy individuals. Titres of 1:200 or greater for either H or O agglutinins were recorded for 75,2% of patients with bacteriologically proven typhoid fever, 4,6% of healthy subjects residing in an endemic area and 7,5% of patients presenting with non-thyroid fevers. Age, sex and region were found to affect the percentage of positive tests recorded. Despite these failings, the Widal test was found to be of value in the diagnosis of typhoid fever. The concept of a diagnostic titre was considered unreliable, but considered in conjunction with the clinical picture, O or H agglutinin titres of 1:200 or more may be regarded as strong presumptive evidence of typhoid fever.