Antenatal screening for Toxoplasma gondii, Cytomegalovirus, rubella and Treponema pallidum infections in northern Benin.

OBJECTIVES

Toxoplasma gondii, cytomegalovirus (HCMV) and rubella virus infections are among the most serious of those contracted during pregnancy in terms of foetal consequences. Toxoplasma, HCMV and rubella antibody screening is unusual in Africa, and there are few published data. The aim of this study was to evaluate the prevalence of these markers among pregnant women in northern Benin on the occasion of routine syphilis screening.

METHODS

Toxoplasma, HCMV and rubella IgG and IgM antibodies were determined in the serum of 283 women attending Saint Jean de Dieu de Tanguiéta hospital, using an enzyme immunoassay, and IgM were confirmed using an enzyme-linked fluorescent assay (ELFA). In the case of IgM positivity, the avidity of anti-HCMV and anti-Toxoplasma IgG was measured. Total anti-Treponema pallidum antibodies were determined using an enzyme immunoassay and confirmed by immunoblotting. In the case of positivity, the Venereal Disease Research Laboratory (VDRL) test was used.

RESULTS

The prevalence of anti-Toxoplasma, anti-HCMV, anti-rubella IgG and total anti-Treponema antibodies was, respectively, 30.0%, 100%, 94% and 2.5%. The VDRL test was positive in 62.5% of the anti-Treponema-positive samples. The prevalence of anti-Toxoplasma, anti-HCMV and anti-rubella IgM was, respectively, 0.4%, 1.4% and 0%. There were no statistically significant differences in terms of age class or trimester of pregnancy. Anti-Toxoplasma and anti-HCMV IgG avidity was always high.

CONCLUSIONS

The prevalence of HCMV and rubella antibodies is high in northern Benin, whereas that of Toxoplasma antibodies is lower. As nearly two-thirds of the pregnant women were anti-Toxoplasma seronegative, antibody screening should be introduced.