{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,4]],"date-time":"2026-06-04T14:37:59Z","timestamp":1780583879841,"version":"3.54.1"},"reference-count":0,"publisher":"Cambridge University Press (CUP)","issue":"4","license":[{"start":{"date-parts":[[1998,4,1]],"date-time":"1998-04-01T00:00:00Z","timestamp":891388800000},"content-version":"unspecified","delay-in-days":0,"URL":"https:\/\/www.cambridge.org\/core\/terms"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Parasitology"],"published-print":{"date-parts":[[1998,4]]},"abstract":"<jats:p>In the savanna areas of tropical Africa, cattle are frequently\n infected with \nthe filaria <jats:italic>Onchocerca ochengi<\/jats:italic>. This parasite is \nclosely related to <jats:italic>Onchocerca volvulus<\/jats:italic>, the causative agent of\n \nhuman onchocerciasis (river blindness), and is capable of \ndeveloping in the same vector, <jats:italic>Simulium damnosum<\/jats:italic> s.l. In North\n \nCameroon, where both <jats:italic>O. ochengi<\/jats:italic> and <jats:italic>O. volvulus<\/jats:italic> are \nendemic, we carried out a field study (reported in this and 2 following\n \npapers) to examine to which extent the transmission \nof the 2 parasite species overlap and what influence this has on the \nepidemiology of human onchocerciasis. In this paper \nwe report our experiments to determine which of the <jats:italic>S. damnosum<\/jats:italic>\n \nspecies in North Cameroon act as vectors of <jats:italic>O. ochengi<\/jats:italic>, \nhow efficiently they do so and whether other <jats:italic>Simulium<\/jats:italic> species\n play \na vector role. To this end, infected cattle were exposed \nnear 5 rivers in different geographical areas. Among 14 <jats:italic>Simulium<\/jats:italic>\n \nspecies identified as aquatic and\/or adult stages at these \nrivers, only 6 (<jats:italic>S. squamosum<\/jats:italic>, <jats:italic>S. damnosum<\/jats:italic> s.s., <jats:italic>S.\n sirbanum<\/jats:italic>, \n<jats:italic>S. bovis<\/jats:italic>, <jats:italic>S. wellmanni<\/jats:italic> and <jats:italic>S. hargreavesi<\/jats:italic>) were\n found to bite \ncattle in important numbers in at least 1 of the sites. The 3 species of\n the \n<jats:italic>S. damnosum<\/jats:italic> complex were all capable of \ningesting microfilariae (mf) of <jats:italic>O. ochengi<\/jats:italic> and developing a proportion\n \nof them to infective larvae (L3). Whereas <jats:italic>S. \nsquamosum<\/jats:italic> and <jats:italic>S. damnosum<\/jats:italic> s.s., the prevailing vectors in\n the \nGuinea and Sudan savanna respectively, showed a high \nvector competence (17% of ingested mf developed to L3), <jats:italic>S. sirbanum<\/jats:italic>,\n \nwhich was much rarer in both areas, appeared to \nhave a much lower susceptibility (2%). Other boophilic <jats:italic>Simulium<\/jats:italic>\n \nspecies were only seen in certain sites and seasons, being \neither incapable of ingesting important numbers of <jats:italic>O. ochengi<\/jats:italic>\n mf \nfrom body regions where these mf were abundant (<jats:italic>S. \nbovis<\/jats:italic>, <jats:italic>S. hargreavesi<\/jats:italic>); not able to support the development\n \nof ingested mf to L3 (<jats:italic>S. wellmanni<\/jats:italic>), or bit cattle preferentially\n \nin the ears, where <jats:italic>O. ochengi<\/jats:italic> mf do not occur (<jats:italic>S. hargreavesi<\/jats:italic>).\n \nWe conclude that in North Cameroon members of the <jats:italic>S. damnosum<\/jats:italic>\n \ncomplex are the only important vectors of <jats:italic>O. ochengi<\/jats:italic>, with \n<jats:italic>S. squamosum<\/jats:italic> and <jats:italic>S. damnosum<\/jats:italic> s.s. being the main vectors.<\/jats:p>","DOI":"10.1017\/s0031182097002333","type":"journal-article","created":{"date-parts":[[2002,7,27]],"date-time":"2002-07-27T13:30:22Z","timestamp":1027776622000},"page":"327-336","source":"Crossref","is-referenced-by-count":20,"title":["<i>Onchocerca ochengi<\/i>: assessment of the <i>Simulium<\/i> \nvectors in\n North Cameroon"],"prefix":"10.1017","volume":"116","author":[{"given":"G.","family":"WAHL","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"D.","family":"EKALE","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"A.","family":"SCHMITZ","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"56","published-online":{"date-parts":[[1998,4,1]]},"container-title":["Parasitology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.cambridge.org\/core\/services\/aop-cambridge-core\/content\/view\/S0031182097002333","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2019,4,6]],"date-time":"2019-04-06T18:59:53Z","timestamp":1554577193000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.cambridge.org\/core\/product\/identifier\/S0031182097002333\/type\/journal_article"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1998,4]]},"references-count":0,"journal-issue":{"issue":"4","published-print":{"date-parts":[[1998,4]]}},"alternative-id":["S0031182097002333"],"URL":"https:\/\/doi.org\/10.1017\/s0031182097002333","relation":{},"ISSN":["0031-1820","1469-8161"],"issn-type":[{"value":"0031-1820","type":"print"},{"value":"1469-8161","type":"electronic"}],"subject":[],"published":{"date-parts":[[1998,4]]}}}