Search

Substantial uncertainties surround the sensitivities and specificities of diagnostic techniques for urinary schistosomiasis. We used latent class (LC) modeling to address this problem. In this study, 220 adults in three villages northwest of Accra, Ghana were examined using five Schistosoma haematobium diagnostic measures: microscopic examination of urine for detection of S. haematobium eggs, dipsticks for detection of hematuria, tests for circulating antigens, antibody tests, and ultrasound scans of the urinary system. Testing of the LC model indicated non-invariance of the performance of the diagnostic tests across different age groups, and measurement invariance held for males and females and for the three villages. We therefore recommend the use of LC models for comparison between and the identification of the most accurate schistosomiasis diagnostic tests. Furthermore, microscopy and hematuria dipsticks were indicated through these models as the most appropriate techniques for detection of S. haematobium infection.

The potential relationship between Schistosoma mansoni and anemia was examined using data obtained by the Schistosomiasis Control Initiative (SCI) before (baseline) and 1 year after (follow-up) a chemotherapeutic treatment program in Uganda. Changes in hemoglobin (Hb) levels in 2,788 children in relation to their schistosomiasis and/or hookworm infection intensity category and baseline anemia status were analyzed. At baseline, significant predictors of childhood anemia were intensities of S. mansoni and hookworm infection. At follow-up, moderate or heavy hookworm as well as heavy S. mansoni infections were important. Children heavily infected with S. mansoni or hookworm had significantly lower Hb counts at baseline compared with those not infected. Among anemic children at the baseline survey, a significant increase in Hb counts of 0.834 g/dL after treatment was found. Our results suggest that anemia is associated with schistosomiasis and hookworm in Ugandan children and that such anemia shows a significant improvement after chemotherapy.