PREVALENCE OF TRACHOMA AMONG DISPLACED PERSONS IN THE SUDAN - A CLINICAL AND SEROEPIDEMIOLOGIC STUDY

The prevalence of trachoma was determined among displaced persons from the north, west and south of The Sudan who had settled in Angola Village, Omdurman County. Of 616 persons examined, 376 (61%) were found to have clinical signs of active trachoma. Of the 448 children, aged 4 months to 15 years, 55 (12%) had mild, 69 (15%) moderately severe, and 210 (47%) severe disease. The corresponding figures for those aged 16 and older (adults) were 5 (3%), 12 (7%) and 25 (15%), respectively. The prevalence of active trachoma among the children in the village was 75%, being higher among those from southern (86%) Sudan than for those from the northern (64%) and western (66%) regions. The corresponding figures for the adults were 25%, 38%, 13% and 14%. Antibodies to Chlamydia trachomatis were found in the lachrymal fluid of 224 (67%) and in the serum of 272 (81%) of the children tested. A higher (74%) prevalence rate of antibody-positive tears was found in children from the south than from either northern (58%) or western (61%) Sudan. The corresponding percentages of antibody-positive sera were 90%, 72% and 73%. In the adults, antibodies to C. trachomatis were found in tears of 28 (67%). As in the children, the proportion of adults with antibody-positive tears was higher among those from the south (80%) than in those from north or west Sudan (25% and 38%, respectively). This was also true of the prevalence of serum antibodies, which was 93% versus 75% and 75%, respectively. Trachoma is still common in The Sudan among persons of low socio-economic status. Our investigations also showed that the prevalence can differ between ethnic groups originating from different regions in spite of them having lived in the same place, often for years, and under the same primitive and trachoma-promoting conditions. Close family ties thus seem to be of greater importance in the prevalence of trachoma than do environmental conditions.