Epidemiology and aetiology of urethritis in Swaziland.

The annual incidence of urethritis can be estimated to be at lest 3750 per 100,000 population in Swaziland. In a study of 109 males with symptomatic urethritis 80% had gonorrhoea, 6% non-gonococcal urethritis (ngu) and 14% were classified as having no 'objective' urethritis (less than 5 polymorphonuclear leucocytes per highpower field in the urethral smear). The relative frequency of gonorrhoea was 80 to 95% and of non-gonococcal urethritis 5 to 20 according to which criteria are used for patient selection and/or diagnosis of ngu. Chlamydia trachomatis was cultured in 3.4% of the cases with urethritis, comprising one positive culture in 70 patients with gonorrhoea, one in 5 with ngu, and one in 12 with no 'objective' urethritis. Seventy-one percent of patients, with a comparable percentage in each diagnostic group, had chlamydial antibodies when tested by the micro immunofluorescence test to pooled chlamydial antigens. Interpretation of the chlamydial serologic results indicates that lymphogranuloma venereum is probably endemic in the country, and that oculogenital chlamydial infections are not a problem; this corresponds with the low isolation rate of Chlamydia trachomatis in the urethritis cases. The study shows that the epidemiology and causes of urethritis are clearly of a different pattern to that seen in industrialised countries. This type of study is a sound basis for a simplified but effective urethritis control programme which can be implemented in the para-urban and rural health centres in developing countries.