Impact of Three to Five Rounds of Mass Drug Administration on Schistosomiasis and Soil-Transmitted Helminths in School-Aged Children in North-Central Nigeria

• Published in: The American journal of tropical medicine and hygiene 2022-07, Vol.107 (1), p.132-142
• Main Authors: Griswold, Emily, Eigege, Abel, Adelamo, Solomon, Mancha, Bulus, Kenrick, Nwodu, Sambo, Yohana, Ajiji, Joseph, Zam, Gideon, Solomon, Jacob, Urude, Rita, Kadimbo, Jonathan, Danboyi, Jacob, Miri, Emmanuel, Nute, Andrew W, Rakers, Lindsay, Nebe, Obiageli, Anyaike, Chukwuma, Weiss, Paul, Noland, Gregory, Richards, Frank
• Format: Article
• Language: English
• Subjects: Parasites; Schools
• ISSN: 0002-9637; 1476-1645
• DOI: 10.4269/ajtmh.21-1207

Nasarawa and Plateau states of north-central Nigeria have implemented programs to control schistosomiasis (SCH) and soil-transmitted helminths (STH) in children since the 1990s. Statewide mapping surveys were conducted in 2013, when 11,332 school-aged children were sampled from 226 schools. The local government areas (LGAs) then received varying combinations of mass drug administration (MDA) for the next 5 years. We revisited 196 (87%) schools in 2018 plus an additional six (202 schools in total), sampling 9,660 children. We calculated overall prevalence and intensity of infection and evaluated associations with gender; age; behaviors; water, sanitation, and hygiene (WASH); and treatment regimen. Urine heme detection dipsticks were used for Schistosoma hematobium in both surveys, with egg counts added in 2018. Stool samples were examined by Kato-Katz for Ascaris lumbricoides, Trichuris trichiura, Schistosoma mansoni, and hookworm. Schistosomiasis prevalence among sampled students dropped from 12.9% (95% confidence interval [CI]: 11.1-14.9%) to 9.0% (95% CI: 7.5-10.9%), a statistically significant change (P < 0.05). In 2018, eight LGAs still had > 1% of children with heavy-intensity schistosome infections. Prevalence of STH infection did not significantly change, with 10.8% (95% CI: 9.36-12.5%) of children positive in 2013 and 9.4% (95% CI: 8.0-10.9%) in 2018 (P = 0.182). Heavy-intensity STH infections were found in < 1% of children with hookworm, and none in children with A. lumbricoides or T. trichiura in either study. The WASH data were collected in 2018, indicating 43.6% of schools had a latrine and 14.4% had handwashing facilities. Although progress is evident, SCH remains a public health problem in Nasarawa and Plateau states.