Post-treatment Prevalence of Schistosomiasis and Geohelminthic Infections in Children and Adults Living along Lake Victoria, Kenya
Schistosomiasis and geohelminthic infections are major public health problems in developing countries and exert a heavy burden on morbidity when they occur singly or concurrently. Chemotherapeutic approach has been adopted in many endemic areas, using praziquantel and albendazole, based on World Health Organization (WHO) recommendations for control. The need for cost-effectiveness considerations in control strategies requires that greater emphasis be placed on further research to understand the factors that determine their occurrence and response to chemotherapy when they occur singly or concurrently. Towards this, a longitudinal survey in Kisumu and Siaya counties, Kenya, was conducted to assess the post-treatment prevalence of Schistosoma mansoni, Trichuris trichiura, Ascaris lumbricoides and hookworms in school children (9–12 years) and adults over a 9-month period (September 2008 – May 2009). Adults were followed up monthly, while children were followed up every two months. Baseline prevalence of schistosomiasis was 52.0% + 2.5% in adults, and 38.5% + 1.8% in children while that of geohelminthiasis was 22.5% + 3.9% and 55.6% + 4.1% in adults and school children respectively. The difference in prevalence between the adults and children for both schistosomiasis and geohelmithes was not significant (P=0.9302), After 9 and 5 treatments in adults and children respectively, there was reduction in prevalence of schistosomiasis to 28.9% + 2.3% and 24.0% + 3.1% in adults and children respectively, while in geohelminthiasis prevalence reduced to 4.3% + 1.5% in adults and 27.0% + 2.5% in school children. These difference in prevalence among adults and children was not significant (P=0.8717). This study shows the differential occurrence of schistosomiasis and geohelmiths in children and adults. It also shows that frequent and consistent treatment decreases the prevalence of helminths in endemic areas and is effective both in adults and children. There’s however need for further studies to determine the most cost-effective strategies for mass drug administration, that will impact morbidity caused by helminths to sustainable levels in vulnerable groups.