Comparison of diagnostic performance of single and multiple fecal sampling in the detection of soil-transmitted helminths in school-aged children

Soil-transmitted helminths (STHs) are widely distributed globally and India is a significant contributor to the overall global burden of the disease. Microscopic methods like Kato-Katz (K-K) thick smear and direct smear microscopy by wet mount (DSM) are widely used for STH diagnosis due to their ease in performance. Still, low sensitivity proves to be a significant limitation of these methods. This study explores the diagnostic performance of two and three consecutive-day stool samples compared to the common practice of single stool sample examination. We observed that the three consecutive-day stool examination technique increased overall helminth positivity from 12% to 16.3% in K-K and 11.5-15.9% in DSM, indicating that multiple sampling can diagnose intestinal helminthiasis more accurately. A significant increase in the intensities of hookworms (by 37.5%; p value: 0.001) and Trichuris trichiura (by 47.8%; p value: 0.037) (measured in terms of fecal egg count) was also observed. The methods undertaken in the current study are comparable in detecting the helminths as the marginal increase in positivity by K-K (16.32% vs. 15.86%) was statistically insignificant.