Syphilis in women of reproductive age in Mogadishu, Somalia: serological survey

Abstract

In Mogadishu, Somalia 223 women of childbearing age, including prostitutes, were tested for serum markers for syphilis by the Venereal Disease Research Laboratory (VDRL) test and the Treponema pallidum haemagglutination assay (TPHA). Sera reactive in either of these tests were tested for IgM antibodies by solid phase haemadsorption assay (SPHA). Three per cent of sera from 67 pregnant women and none of those from 71 educated women gave positive results that were confirmed with the TPHA. In contrast, 58% of sera from 85 prostitutes were confirmed as being positive, 26% of which were SPHA positive, which indicated active syphilis. The proportion of TPHA positive sera increased with age among the prostitutes. As venereal syphilis is highly prevalent in prostitutes in Mogadishu, a strategy of intervention based on screening followed by treatment seems to be indispensable.

PIP: Three different groups of women were studied in a cross sectional survey conducted during July to August 1985 and in January 1986 in Mogadishu, Somalia. The survey population consisted of: 67 pregnant women (aged 16 to 40); 71 educated women volunteers, (aged 15 to 44); and 85 prostitutes (aged 14 to 48). A standardized protocol elicited data about age, occupation, pregnancies, history of syphilis, and number of clients. Blood samples were taken, and all sera were screened by the Venereal Disease Research Laboratory (VDRL) test and the Treponema pallidum hemagglutination assay (TPHA). The positive sera were tested for IgM antibodies by the solid phase hemadsorption assay (SPHA). Of the 67 pregnant women, two (3%) had positive VDRL test results that were confirmed by TPHA. Three (4%) of the sera from the 71 educated women were reactive in the VDRL test, but the VDRL reactions were false positive. Of the 85 prostitutes, 50 were VDRL positive; 38 of them were confirmed positive by TPHA. The remaining 12 (14%) sera were false positive VDRL reactions. Positive TPHA results in the absence of a reactive VDRL test were found in 11 (13%) of the 85 sera tested. Thus, 49 (58%) of the sera from prostitutes gave positive reactions in the TPHA. The predictive value of a positive VDRL test result was 76%. Of the 49 seropositive prostitutes, 15 (31%) had a history of syphilis, whereas of the 36 seronegative prostitutes, only four (11%) had had syphilis earlier. The positive TPHA results increased with the age of the prostitutes (p = 0.03). IgM antibodies were not detected by the SPHA in VDRL or TPHA positive sera from the pregnant or the educated women, whereas 13 (15%) of the sera from the prostitutes were SPHA positive. All sera that were negative in the VDRL test were negative in the SPHA. One of the 13 prostitutes who had IgM antibodies was pregnant at the time of the study. 45 (82%) of 55 prostitutes claimed to have had only local clients and these 55 had 1-105 sexual partners a week.