Observations on the diagnosis of typhoid fever in an endemic area

The problem of providing laboratory confirmation of the diagnosis of typhoid in an endemic area was considered. A consecutive series of pyrexial patients was studied clinically, by blood and stool culture, the Widal reaction, the Sclavo rapid slide test and the diazo reaction. High Widal titres at even very early stages of typhoid suggested an anamnestic response. However, few non-typhoid cases had detectable Widal titres, and it seems, therefore, that though post-typhoid levels of antibody may be very low or even undetectable, further contact gives rise to a secondary response. Diagnostic criteria based upon a single Widal reading should be established for endemic areas, since rising titres may not be demonstrable. Though the rapid slide tests and the diazo reaction may be of some use in screening procedures in non-endemic areas, the results in endemic areas are likely to be confusing.S. Afr. Med. J., 48, 1368 (1974)