Interrupting seasonal transmission of Schistosoma haematobium and control of soil-transmitted helminthiasis in northern and central Côte d’Ivoire: a SCORE study protocol

Abstract

BackgroundTo achieve a world free of schistosomiasis, the objective is to scale up control and elimination efforts in all endemic countries. Where interruption of transmission is considered feasible, countries are encouraged to implement a comprehensive intervention package, including preventive chemotherapy, information, education and communication (IEC), water, sanitation and hygiene (WASH), and snail control. In northern and central Côte d’Ivoire, transmission of Schistosoma haematobium is seasonal and elimination might be achieved. In a cluster-randomised trial, we will assess different treatment schemes to interrupt S. haematobium transmission and control soil-transmitted helminthiasis over a 3-year period. We will compare the impact of (i) arm A: annual mass drug administration (MDA) with praziquantel and albendazole before the peak schistosomiasis transmission season; (ii) arm B: annual MDA after the peak schistosomiasis transmission season; (iii) arm C: two yearly treatments before and after peak schistosomiasis transmission; and (iv) arm D: annual MDA before peak schistosomiasis transmission, coupled with chemical snail control using niclosamide.Methods/designThe prevalence and intensity of S. haematobium and soil-transmitted helminth infections will be assessed using urine filtration and Kato-Katz thick smears, respectively, in six administrative regions in northern and central parts of Côte d’Ivoire. Once a year, urine and stool samples will be collected and examined from 50 children aged 5–8 years, 100 children aged 9–12 years and 50 adults aged 20–55 years in each of 60 selected villages. Changes in S. haematobium and soil-transmitted helminth prevalence and intensity will be assessed between years and stratified by intervention arm. In the 15 villages randomly assigned to intervention arm D, intermediate host snails will be collected three times per year, before niclosamide is applied to the selected freshwater bodies. The snail abundance and infection rates over time will allow drawing inference on the force of transmission.DiscussionThis cluster-randomised intervention trial will elucidate whether in an area with seasonal transmission, the four different treatment schemes can interrupt S. haematobium transmission and control soil-transmitted helminthiasis. Lessons learned will help to guide schistosomiasis control and elimination programmes elsewhere in Africa.Trial registrationISRCTN ISRCTN10926858. Registered 21 December 2016. Retrospectively registered.

Persistent Hotspots in Schistosomiasis Consortium for Operational Research and Evaluation Studies for Gaining and Sustaining Control of Schistosomiasis after Four Years of Mass Drug Administration of Praziquantel

“…A description of the overall study, its methods, and baseline data have been published. 10,[25][26][27][28][29][30] In brief, the sustaining control studies in Côte d'Ivoire and Kenya compared villages that were shown in eligibility testing to have schistosomiasis prevalence of 10-24%. There were three study arms, with 25 villages per arm.…”

Impact of Different Mass Drug Administration Strategies for Gaining and Sustaining Control of Schistosoma mansoni and Schistosoma haematobium Infection in Africa

“…A separate report in this issue 11 presents the results of separate SCORE studies that focused on "moving toward elimination" on Zanzibar and in S. haematobium-endemic areas of northern and central Côte d'Ivoire. 12…”

Schistosomiasis Burden and Its Association With Lower Measles Vaccine Responses in School Children From Rural Cameroon

“…Utzinger's and Raso's groups ( 16 – 18 ) elegantly reported on the reduction of schistosomiasis transmission in regions of northern and central Cote d'Ivoire where the MDA campaigns were complemented with health education and community-led pro-sanitary practices tailored to these sites. These studies had initially mapped the determinants of schistosomiasis prevalence and disease in the targeted regions of Cote d'Ivoire ( 17 ) revealing a critical lack on the means of stopping schistosomiasis transmission and the overlooked community-led sanitary habits that might help prevent transmission.…”