SCORE Mozambique <i>S. haematobium</i> Cluster Randomized Trial

Related studies: SCORE S. mansoni Cluster Randomized Trial Background: Schistosomiasis is a parasitic disease caused by infection with blood flukes of the genus Schistosoma. It is a major public health problem in Mozambique. An epidemiological survey between 2005 and 2007 showed that the mean estimated prevalence of urogenital schistosomiasis, Schistosoma haematobium, was 47% while that of intestinal schistosomiasis, S. mansoni, was much lower ( about 1%) across all of Mozambique. In Cabo Delgado province, the area where this study took place, the prevalence of S. haematobium was 57.9%, ranging from 8.8% on the coast to 93% inland. Mass drug administration (MDA) with the drug praziquantel is the mainstay of global schistosomiasis control. The Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) was established in 2008 to answer strategic questions about schistosomiasis control. Existing thresholds for implementation of mass treatment for schistosomiasis needed refinement and a better evidence base to establish the relative benefits of different age-group coverage formats and different schedules of targeted mass praziquantel delivery. There was interest in finding out whether, when compared with school-based treatment, using one or more years of community-wide treatment would have a greater impact on the prevalence and intensity of infection if, for example, community-wide treatment could achieve better coverage of school-aged children who did not attend school or better coverage of high-risk adults. There also was a lack of data as to whether every-other-year delivery of MDA could be sufficient for morbidity control. Objectives: The primary research question of this study is which strategy for MDA provided the greatest reduction in prevalence and intensity of S. haematobium infection among 9-to-12-year olds after four years of intervention in Cabo Delgado, Northern Mozambique. In addition, the impact of treatment on first-year students and adults sampled in each village was also assessed. These findings were designed to provide an evidence base for the Mozambique national control programme for schistosomiasis to address strategic questions about schistosomiasis treatment and potentially shift from morbidity control to interruption of transmission, and subsequently elimination. Methodology Study Sites: This study was conducted in 150 villages in 10 out of 17 districts of Mozambique's northernmost province, Cabo Delgado. The area was chosen as previous mapping had shown a high prevalence of S. haematobium. Dates of Data Collection: 2011- 2015 Study Design: Cluster-randomized trial with five years of follow up. Study Arms: The 150 study villages were randomized to six study arms as follows. The study arms describe the treatment schedule received by the village over the 4 years of the intervention where s=school based treatment, c= community wide treatment, h=drug holiday. Arm 1 (cccc) villages received community-wide MDA each year. Arm 2 (ccss) villages received 2 years of community-wide MDA followed by 2 years of school-based MDA. Arm 3 (cchh) villages received two years of school-based MDA followed by two years of drug holidays. Arm 4 (ssss) villages received school-based MDA (mass drug administration with the drug praziquantel) each year. Arm 5 (sshh) villages received 2 years of school-based MDA followed by 2 years of drug holiday. Arm 6 (shsh) villages received alternate years of school-based MDA and drug holidays. Data Collection: Village-level data: Data was collected from each study village on geographic location (latitude, longitude) and data related to MDA coverage- total village population, population treated by MDA, number of school-aged children, number of school-aged children treated by MDA. Individual-level data: In each school, 50 boys and 50 girls were selected using systematic random sampling from those in the second, third and fourth classes. In addition, 50 children in the 5-8 year group and 50 adults were sampled from each village in the first and last year of the study. Demographic data on age and sex was collected from each participant. In each school, selected children were asked to provide a single urine specimen. Two filtrations of 10mL each were carried out on the urine sample. Filters were examined for S. haematobium eggs under a light microscope and the number of S. haematobium eggs were counted. ClinEpiDB Data Integration: Data files were provided to ClinEpiDB as cleaned .csv files with all personal identifiers removed. All dates were obfuscated per individual through the application of a random number algorithm that shifted dates no more than seven days to comply with the ethical conduct of human subjects research. Acknowledgements: We thank the technicians from different institutions of Mozambique for their support in the field and the laboratory. We are grateful to the health, education and village authorities of all districts for their contribution. Finally, we thank all the children, parents, teachers and village leaders who participated in this study. Financial Support: SCORE is funded by the Bill & Melinda Gates Foundation through a grant to the University of Georgia Research Foundation (UGARF). Ethics Statement: Informed consent was obtained from all individuals ≥18 years of age and from parents or legal guardians of children less than 18 years of age. The purpose of the study was explained to all schoolchildren and verbal assent was obtained from the children. Permission was also obtained from school headmasters. Ethical clearance was obtained from the National Bio-ethical Committee for Health of Mozambique (NBCHM), and the survey was conducted according to NBCHM guidelines (reference no. IRB00002657). The trial is registered with the International Standard Randomised Controlled Trial registry under ISRTC number 14117624 for Mozambique. The study protocol was also approved by Imperial College London (ICREC_10_2_2). Last Updated: March 8, 2021The SCORE S. haematobium studies in Mozambique were community-level, cluster-randomized control trials designed to understand the impact of different schistosomiasis treatment strategies involving community-wide treatment, school-based treatment, and treatment holidays over a five-year period. Major outcomes were prevalence and intensity of schistosomiasis among 9 to 12 year old children, the highest risk group, at the end of the study. Four rounds of treatment, regardless of whether it was given in the community or school, resulted in a significantly greater reduction of S. haematobium prevalence than two rounds of treatment over a five-year period.