Stomach VolvulusOnchocerca volvulusIntestinal VolvulusStomachGastrointestinal TractOnchocerciasisOnchocercaDigestive SystemSimuliidaeIvermectinIntestinal ObstructionColon, SigmoidCecal DiseasesOnchocerciasis, OcularStomach NeoplasmsDigestive System Physiological PhenomenaUpper Gastrointestinal TractGastrointestinal NeoplasmsMicrofilariaColonic NeoplasmsStomach DiseasesGastrointestinal DiseasesColonic DiseasesAntigens, HelminthGastric MucosaIntestinal MucosaLower Gastrointestinal TractIntestine, SmallColon, TransverseColon, DescendingIntestinesCecumFilaricidesDigestive System AbnormalitiesIntestine, LargeGastrointestinal MotilityStomach UlcerColonMansonelliasisDNA, HelminthAntibodies, HelminthDuodenumColon, AscendingUrinary Tract InfectionsTorsion AbnormalityIleumDigestive System Surgical ProceduresRadiography, Abdominal