Two Practical and Cost Effective Methods for Urinary Schistosomiasis Screening in Yemeni Schoolchildren

Background: The study was conducted to estimate and compare the validity and performance of two screening methods for urinary schistosomiasis: the interview – reporting blood in urine- and detecting microhematuria by reagent strip. Methods: In year 2003, 515 schoolchildren from five schools in Abyan and Taiz governorates in Yemen, were interviewed by healtworker for hematuria, and then urine samples were collected and tested for microhematuria by urine strip and for the presence and count of Schistosoma hematobium by filtration method. Validity and performance indicators were estimated and compared for the two methods using the filtration method as the reference - standard – test. Results: The mean age of the schoolchildren was 10.7±2.5 years. Boys represented 65% of the sample. The prevalence of the infection as determined by filtration, interview and reagent strip methods was 21.4%, 22.15, and 30.9%, respectively. Sensitivity, specificity, PPV, NPV of the urine strip was higher than the same indicators for the interview method. Combining the results of both screening methods increased all validity and performance indicators. A statically significant (P< 0.001) association was found between urine strip positivity level and infection intensity. Conclusion: The urine strip had higher validity and performance indicators than the interview method. For its low –cost, simple and rapid application, we recommend using it for screening infected schoolchildren in areas endemic with S. hematobium in combination with the interview method to enhance its performance.