Seroprevalence and Risk Factors of Toxoplasma gondii Infection among Pregnant Women in Kumasi: A Cross-Sectional Study at a District-Level Hospital, Ghana

Abstract

Background. This study investigated the prevalence and risk factors of Toxoplasma gondii infection among pregnant women in a district-level hospital in Ghana and compared the diagnostic performance of the rapid diagnostic test (RDT) and enzyme-linked immunosorbent assay (ELISA) for T. gondii diagnosis. Method. This cross-sectional study included 400 consecutive consenting women in their first-trimester stage of pregnancy. A validated well-structured closed-ended questionnaire was used to collect sociodemographic data and possible risk factors of each participant. Blood samples were collected for analysis of T. gondii IgG and IgM using the commercial ELISA Kit and RDT. Results. Seroprevalence of toxoplasmosis was 21.5% and 57.3% based on the RDT and ELISA technique, respectively. Secondary education ( $\text{cOR}=1.9$ , 95% CI (1.1-3.1), and $p=0.020$ ) and contact with cats ( $\text{cOR}=1.7$ , 95% CI (1.1-2.8), and $p=0.030$ ) were significant predictors of T. gondii infection, with the former being the only independent risk factor for T. gondii infection ( $\text{aOR}=1.8$ , 95% CI (1.0-3.0), and $p=0.034$ ) by the ELISA method. The sensitivity, specificity, and area under the curve (AUC) of RDT-IgM against ELISA were 42.9%, 95.9%, and 0.694, respectively, whereas those of RDT-IgG were 31.0%, 91.2%, and 0.611, respectively. The diagnostic consistency between the two methods was fair for both RDT-IgM ( $\kappa =0.304$ ) and RDT-IgG ( $\kappa =0.201$ ). Conclusion. The prevalence of T. gondii infection among pregnant women at Kumasi is 21.5% and 57.3% based on the RDT and ELISA technique, respectively. Secondary education and contact with cats were the major risk factors of T. gondii infection. Using ELISA as the reference, the RDT used in this study for the diagnosis of T. gondii infection has low sensitivity, and therefore, it is unreliable. However, this finding does not invalidate all RDTs because there are several other brands of RDT with good sensitivity and specificity. Further studies to ascertain the performance of other commercially available RDT kits are needed.