{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,31]],"date-time":"2026-07-31T07:05:47Z","timestamp":1785481547876,"version":"3.56.0"},"reference-count":93,"publisher":"Cambridge University Press (CUP)","issue":"4","license":[{"start":{"date-parts":[[2009,4,6]],"date-time":"2009-04-06T00:00:00Z","timestamp":1238976000000},"content-version":"unspecified","delay-in-days":5089,"URL":"https:\/\/www.cambridge.org\/core\/terms"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Parasitology"],"published-print":{"date-parts":[[1995,5]]},"abstract":"<jats:title>SUMMARY<\/jats:title><jats:p>A previous paper reported that the intake of<jats:italic>Onchocerca volvulus<\/jats:italic>microfilariae (mff) by different species of<jats:italic>Simulium<\/jats:italic>is essentially proportional to the parasite load in the skin of infected carriers. This paper examines the fate of the ingested mff in susceptible vectors to assess the relationship between parasite intake and infective larval output in blackfly species with and without well-developed cibarial armatures. Analysis is based on data from 3 onchocerciasis endemic areas: Guatemala (<jats:italic>S. ochraceum s.l.<\/jats:italic>), West Africa (<jats:italic>S. damnosum s.l.\/S. sirbanum<\/jats:italic>) and the Amazonian focus between South Venezuela and Northern Brazil (<jats:italic>S. guianense<\/jats:italic>and<jats:italic>S. oyapockense s.l.<\/jats:italic>). The data, which include published and unedited information collected in the field, record experimental studies of parasite uptake by wild flies maintained in captivity until the completion of the extrinsic incubation period. The relationship between L3 output (measured as the mean number of successful larvae\/fly or, as the proportion of flies with infective larvae) and average microfilarial intake, was strongly non-linear. This non-linearity was best represented by a sigmoid function in case of armed simuliids (<jats:italic>S. ochraceum s.l., S. oyapockense s.l.<\/jats:italic>), or by a hyperbolic expression in that of unarmed flies (<jats:italic>S. damnosum s.l., S. guianense<\/jats:italic>). These results are compatible, respectively, with the patterns of \u2018initial facilitation\u2019 and \u2018limitation\u2019 described in culicid vectors of lymphatic filariases. A maximum mean number of 1\u20133 L3\/fly was observed in all 4 vectors. It is concluded that<jats:italic>O. volvulus<\/jats:italic>larval development to the infective stage is regulated by density-dependent mechanisms acting at the early phase of microfilarial migration out of the blackfly's bloodmeal. Damage by the bucco-pharyngeal armature may also be density dependent. A hypothesis, based on this density dependence is forwarded to explain initial facilitation, so far only recorded in vectors with well-developed cibarial teeth. Our results provide quantitative support for the conjecture that chemotherapy alone is likely to have a greater impact on reducing onchocerciasis transmission in endemic areas where the main vector has a toothed fore-gut than in foci where the vectors have unarmed cibaria.<\/jats:p>","DOI":"10.1017\/s0031182000064751","type":"journal-article","created":{"date-parts":[[2009,6,5]],"date-time":"2009-06-05T13:47:51Z","timestamp":1244209671000},"page":"409-427","source":"Crossref","is-referenced-by-count":51,"title":["Density-dependent processes in the transmission of human onchocerciasis: relationship between the numbers of microfilariae ingested and successful larval development in the simuliid vector"],"prefix":"10.1017","volume":"110","author":[{"given":"M. G.","family":"Bas\u00e1\u00f1ez","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"J. H. F.","family":"Remme","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"E. S.","family":"Alley","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"O.","family":"Bain","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"A. J.","family":"Shelley","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"G. F.","family":"Medley","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"R. M.","family":"Anderson","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"56","published-online":{"date-parts":[[2009,4,6]]},"reference":[{"key":"S0031182000064751_ref076","first-page":"177","article-title":"Large scale ivermectin distribution and its epidemiological consequences","volume":"59","author":"Remme","year":"1990","journal-title":"Acta Leidensia"},{"key":"S0031182000064751_ref075","doi-asserted-by":"publisher","DOI":"10.1080\/00034983.1984.11811859"},{"key":"S0031182000064751_ref018","doi-asserted-by":"publisher","DOI":"10.1016\/0035-9203(88)90286-6"},{"key":"S0031182000064751_ref074","doi-asserted-by":"publisher","DOI":"10.1111\/j.1365-2915.1994.tb00512.x"},{"key":"S0031182000064751_ref069","first-page":"517","article-title":"Rendement parasitaire chez les vecteurs de filarioses","volume":"51","author":"Pichon","year":"1974","journal-title":"Bulletin of the World Health Organization"},{"key":"S0031182000064751_ref065","first-page":"109","article-title":"Lethal damage to Simulium metallicum following high intakes of Onchocerca volvulus microfilariae in Guatemala","volume":"28","author":"Omar","year":"1977","journal-title":"Tropenmedizin und Parasitologie"},{"key":"S0031182000064751_ref060","doi-asserted-by":"publisher","DOI":"10.1016\/0025-5564(77)90030-X"},{"key":"S0031182000064751_ref041","doi-asserted-by":"publisher","DOI":"10.1016\/0169-4758(92)90272-4"},{"key":"S0031182000064751_ref056","doi-asserted-by":"publisher","DOI":"10.1038\/165978b0"},{"key":"S0031182000064751_ref051","doi-asserted-by":"publisher","DOI":"10.1007\/BF00927425"},{"key":"S0031182000064751_ref055","doi-asserted-by":"publisher","DOI":"10.1017\/S0022149X00020976"},{"key":"S0031182000064751_ref057","doi-asserted-by":"publisher","DOI":"10.1017\/S0007485300026705"},{"key":"S0031182000064751_ref053","doi-asserted-by":"publisher","DOI":"10.2307\/3959"},{"key":"S0031182000064751_ref071","first-page":"169","article-title":"The risk and dynamics of onchocerciasis recrudescence after cessation of vector control","volume":"69","author":"Plaisier","year":"1991","journal-title":"Bulletin of the World Health Organization"},{"key":"S0031182000064751_ref044","doi-asserted-by":"publisher","DOI":"10.1111\/j.1365-2915.1991.tb00555.x"},{"key":"S0031182000064751_ref042","doi-asserted-by":"publisher","DOI":"10.1016\/0035-9203(94)90270-4"},{"key":"S0031182000064751_ref081","doi-asserted-by":"publisher","DOI":"10.1007\/978-1-4612-2590-4_7"},{"key":"S0031182000064751_ref040","doi-asserted-by":"publisher","DOI":"10.1146\/annurev.en.37.010192.000245"},{"key":"S0031182000064751_ref035","doi-asserted-by":"publisher","DOI":"10.1080\/00034983.1962.11686118"},{"key":"S0031182000064751_ref028","doi-asserted-by":"publisher","DOI":"10.1080\/00034983.1993.11812738"},{"key":"S0031182000064751_ref025","volume-title":"Analysis of Survival Data","author":"Cox","year":"1984"},{"key":"S0031182000064751_ref054","doi-asserted-by":"publisher","DOI":"10.1080\/00034983.1962.11686105"},{"key":"S0031182000064751_ref022","first-page":"235","article-title":"Quantitative aspects of the infection of Simulium ochraceum by Onchocerca volvulus","volume":"28","author":"Collins","year":"1977","journal-title":"Tropenmedizin und Parasitologie"},{"key":"S0031182000064751_ref021","doi-asserted-by":"publisher","DOI":"10.1080\/00034983.1982.11687581"},{"key":"S0031182000064751_ref019","first-page":"475","article-title":"Quantitative aspects of the infection of Simulium ochraceum by Onchocerca volvulus: the relation of skin microfilarial density to vector infection","volume":"31","author":"Campbell","year":"1980","journal-title":"Tropenmedizin und Parasitologie"},{"key":"S0031182000064751_ref017","doi-asserted-by":"publisher","DOI":"10.1016\/0035-9203(90)90281-I"},{"key":"S0031182000064751_ref015","unstructured":"Boussinesq M. (1991). Etude \u00e9pid\u00e9miologique de l'onchocercose en zone de savane camerounaise. Effets d'un traitement de masse par l'invermectine. Ph.D. thesis, University of Montpellier II."},{"key":"S0031182000064751_ref013","doi-asserted-by":"publisher","DOI":"10.1017\/S0031182000078586"},{"key":"S0031182000064751_ref063","doi-asserted-by":"publisher","DOI":"10.1080\/00034983.1977.11687216"},{"key":"S0031182000064751_ref030","doi-asserted-by":"publisher","DOI":"10.1016\/0035-9203(66)90223-9"},{"key":"S0031182000064751_ref073","first-page":"438","article-title":"Cibarial armature of Simulium vectors of onchocerciasis","volume":"72","author":"Reid","year":"1978","journal-title":"Transactions of the Royal Society of Tropical Medicine and Hygiene"},{"key":"S0031182000064751_ref010","first-page":"467","article-title":"Onchocercose au Guatemala: l'ingestion des microfilaires par Simulium ochraceum et leur passage dans l'h\u00e9moc\u00e9le de ce vecteur","volume":"49","author":"Bain","year":"1974","journal-title":"Annales de Parasitologie (Paris)"},{"key":"S0031182000064751_ref009","first-page":"399","article-title":"Transmission de la wuchereriose et de la s\u00e9tariose bovine: \u00e9tude histologique de la travers\u00e9e de la paroi stomacale d' Anopheles gambiae A et d' Aedes aegypti par les microfilaires","volume":"47","author":"Bain","year":"1972","journal-title":"Annales de Parasitologie (Paris)"},{"key":"S0031182000064751_ref005","doi-asserted-by":"crossref","DOI":"10.1093\/oso\/9780198545996.001.0001","volume-title":"Infectious Diseases of Humans. Dynamics and Control","author":"Anderson","year":"1991"},{"key":"S0031182000064751_ref003","doi-asserted-by":"publisher","DOI":"10.1017\/S0031182000055347"},{"key":"S0031182000064751_ref066","article-title":"Etude de la transmission d'Onchocerca volvulus (Leuckart, 1893) (Nematoda, Onchocercidae) par Simulium damnosum Theobald, 1903 (Diptera, Simuliidae) en Afrique tropicale","author":"Philippon","year":"1977","journal-title":"Travaux et Documents de l' O.R.S.T.O.M. (Paris) No. 63."},{"key":"S0031182000064751_ref001","article-title":"Infectivity of Simulium damnosum s.s. and S. sirbanum in relation to intensity of onchocerciasis infection of the human host in Asubende, Ghana","author":"Alley","year":"1994","journal-title":"Tropical Medicine and Parasitology"},{"key":"S0031182000064751_ref077","doi-asserted-by":"publisher","DOI":"10.1080\/00034983.1987.11812117"},{"key":"S0031182000064751_ref067","first-page":"462","article-title":"Enhanced migration of Brugia pahangi microfilariae through the mosquito midgut following N-acetyl-D-glucosamine ingestion","volume":"84","author":"Phiri","year":"1990","journal-title":"Transactions of the Royal Society of Tropical Medicine and Hygiene"},{"key":"S0031182000064751_ref020","first-page":"469","article-title":"La transmission des parasites par vecteurs h\u00e9matophages: richesse des ph\u00e9nom\u00e8nes adaptatifs","volume":"3","author":"Chabaud","year":"1986","journal-title":"La Vie des Sciences"},{"key":"S0031182000064751_ref006","volume-title":"Statistical Methods in Medical Research","author":"Armitage","year":"1987"},{"key":"S0031182000064751_ref012","first-page":"391","article-title":"Corr\u00e9lation entre le nombre de microfilaires ing\u00e9r\u00e9es et l'\u00e9paisseur de la membrane p\u00e9ritrophique du vecteur dans l'onchocercose de savane africaine","volume":"283","author":"Bain","year":"1976","journal-title":"Comptes Rendus de l 'Acad\u00e9mic Scientifique de Paris"},{"key":"S0031182000064751_ref082","doi-asserted-by":"publisher","DOI":"10.1111\/j.1365-2915.1987.tb00348.x"},{"key":"S0031182000064751_ref004","doi-asserted-by":"publisher","DOI":"10.1016\/S0065-308X(08)60561-8"},{"key":"S0031182000064751_ref002","doi-asserted-by":"publisher","DOI":"10.1007\/978-3-642-93161-1_16"},{"key":"S0031182000064751_ref087","doi-asserted-by":"publisher","DOI":"10.7601\/mez.35.121"},{"key":"S0031182000064751_ref023","first-page":"47","article-title":"Importanza dell' armatura bucco-faringea in Anopheles e Culex in relazione alle infezioni con Dirofilaria","volume":"10","author":"Coluzzi","year":"1968","journal-title":"Parassitologia"},{"key":"S0031182000064751_ref061","doi-asserted-by":"publisher","DOI":"10.1016\/0035-9203(78)90128-1"},{"key":"S0031182000064751_ref027","first-page":"31","article-title":"Genetic variation in the ability of insects to transmit filariae, trypanosomes and malarial parasites","volume":"1","author":"Curtis","year":"1983","journal-title":"Current Topics in Vector Research"},{"key":"S0031182000064751_ref014","first-page":"231","volume-title":"Parasitic Diseases: Treatment and Control","author":"Bas\u00e1\u00f1ez","year":"1989"},{"key":"S0031182000064751_ref048","first-page":"935","article-title":"On the inefficiency of transmission of Wuchereria bancrofti from mosquito to human host","volume":"38","author":"Hairston","year":"1968","journal-title":"Bulletin of the World Health Organization"},{"key":"S0031182000064751_ref026","doi-asserted-by":"publisher","DOI":"10.1016\/0169-4758(92)90267-6"},{"key":"S0031182000064751_ref016","first-page":"235","article-title":"Passage des microfilaires de l'estomac vers l'h\u00e9moc\u00e8le du vector dans les couples Wuchereria bancrofti-Anopheles gambiae A, W. bancrofti-Aedes aegypti et Setaria labiatopapillosa-A. aegypti","volume":"10","author":"Brengues","year":"1972","journal-title":"Cahiers O.R.S.T.O.M. s\u00e9rie Entomologie m\u00e9dicale et Parasitologie"},{"key":"S0031182000064751_ref068","first-page":"199","article-title":"Relations math\u00e9matiques entre le nombre des microfilaires ing\u00e9r\u00e9es et le nombre des parasites chez diff\u00e9rents vecteurs naturelles ou exp\u00e9rimentaux de filarioses","volume":"12","author":"Pichon","year":"1974","journal-title":"Cahiers O.R.S.T.O.M. s\u00e9rie Entomologie m\u00e9dicate et Parasitologie"},{"key":"S0031182000064751_ref032","doi-asserted-by":"publisher","DOI":"10.1007\/978-1-4899-2901-3_7"},{"key":"S0031182000064751_ref064","first-page":"183","article-title":"The fate and migration of microfilariae of a Guatemalan strain of Onchocerca volvulus in Simulium ochraceum and S. metallicum, and the role of the buccopharyneal armature in the destruction of microfilariae","volume":"26","author":"Omar","year":"1975","journal-title":"Tropenmedizin und Parasitologie"},{"key":"S0031182000064751_ref033","doi-asserted-by":"publisher","DOI":"10.1016\/0169-4758(88)90034-8"},{"key":"S0031182000064751_ref080","doi-asserted-by":"publisher","DOI":"10.1590\/S0102-311X1991000300003"},{"key":"S0031182000064751_ref039","doi-asserted-by":"publisher","DOI":"10.1080\/00034983.1964.11686217"},{"key":"S0031182000064751_ref024","doi-asserted-by":"publisher","DOI":"10.1007\/978-1-4899-2887-0"},{"key":"S0031182000064751_ref084","doi-asserted-by":"publisher","DOI":"10.1016\/0035-9203(92)90096-U"},{"key":"S0031182000064751_ref045","doi-asserted-by":"publisher","DOI":"10.4269\/ajtmh.1977.26.75"},{"key":"S0031182000064751_ref062","doi-asserted-by":"publisher","DOI":"10.1016\/0169-4758(93)90030-J"},{"key":"S0031182000064751_ref029","first-page":"396","volume-title":"Black-flies: Ecology, Population Management and Annotated World List","author":"Davies","year":"1987"},{"key":"S0031182000064751_ref046","first-page":"479","article-title":"Infections with Onchocerca volvulus in different members of the Simulium damnosum complex in Togo and Benin","volume":"72","author":"Garms","year":"1985","journal-title":"Zeitschrift f\u00fcr angeviandte Zoologie"},{"key":"S0031182000064751_ref078","first-page":"219","article-title":"Observations on the epidemiology of human filariasis in French Oceania","volume":"61","author":"Rosen","year":"1955","journal-title":"American Journal of Hygiene"},{"key":"S0031182000064751_ref052","first-page":"212","article-title":"Blood meal enhanced Onchocerca development and its correlation with fecundity in laboratory reared blackflies (Diptera, Simuliidae)","volume":"35","author":"Ham","year":"1984","journal-title":"Tropenmedizin und Parasitologie"},{"key":"S0031182000064751_ref059","doi-asserted-by":"publisher","DOI":"10.1016\/0035-9203(65)90152-5"},{"key":"S0031182000064751_ref031","doi-asserted-by":"publisher","DOI":"10.1016\/S0065-308X(08)60530-8"},{"key":"S0031182000064751_ref011","first-page":"1081","article-title":"M\u00e9canisme du passage des microfilaires \u00e0 travers la paroi stomacale du vecteur; son importance dans la transmission de l'onchocercose","volume":"269","author":"Bain","year":"1969","journal-title":"Comptes Rendus de l 'Acad\u00e9mie Scientifique de Paris"},{"key":"S0031182000064751_ref083","volume-title":"Biometry. The Principles and Practice of Statistics in Biological Research","author":"Sokal","year":"1981"},{"key":"S0031182000064751_ref047","doi-asserted-by":"publisher","DOI":"10.1017\/S0031182000079841"},{"key":"S0031182000064751_ref034","doi-asserted-by":"publisher","DOI":"10.1080\/00034983.1962.11686099"},{"key":"S0031182000064751_ref092","doi-asserted-by":"publisher","DOI":"10.1080\/00034983.1957.11685817"},{"key":"S0031182000064751_ref049","doi-asserted-by":"publisher","DOI":"10.1017\/S0031182000064040"},{"key":"S0031182000064751_ref086","doi-asserted-by":"publisher","DOI":"10.2307\/3280961"},{"key":"S0031182000064751_ref088","doi-asserted-by":"publisher","DOI":"10.4269\/ajtmh.1984.33.414"},{"key":"S0031182000064751_ref089","doi-asserted-by":"publisher","DOI":"10.1080\/00034983.1991.11812541"},{"key":"S0031182000064751_ref037","doi-asserted-by":"publisher","DOI":"10.1080\/00034983.1968.11686536"},{"key":"S0031182000064751_ref090","first-page":"241","article-title":"Can anopheline-transmitted filariasis be eradicated ?","volume":"94","author":"Webber","year":"1991","journal-title":"Journal of Tropical Medicine and Hygiene"},{"key":"S0031182000064751_ref093","doi-asserted-by":"publisher","DOI":"10.1080\/00034983.1957.11685832"},{"key":"S0031182000064751_ref058","first-page":"498","article-title":"The development of Onchocerca spp. in Simulium decorum Walker and Simulium pictipesHagen","volume":"31","author":"Lok","year":"1980","journal-title":"Tropenmedizin und Parasitologie"},{"key":"S0031182000064751_ref091","doi-asserted-by":"publisher","DOI":"10.1080\/00034983.1991.11812540"},{"key":"S0031182000064751_ref038","doi-asserted-by":"publisher","DOI":"10.1080\/00034983.1973.11686866"},{"key":"S0031182000064751_ref050","doi-asserted-by":"publisher","DOI":"10.1007\/978-1-4612-2910-0_4"},{"key":"S0031182000064751_ref085","first-page":"172","volume-title":"Tropical and Geographical Medicine","author":"Spielman","year":"1985"},{"key":"S0031182000064751_ref008","first-page":"397","article-title":"Travers\u00e9e de la paroi stomacale du vecteur par les microfilaires: techniques d'\u00e9tude utilis\u00e9es, importance \u00e9pid\u00e9miologique","volume":"54","author":"Bain","year":"1976","journal-title":"Bulletin of the World Health Organization"},{"key":"S0031182000064751_ref007","first-page":"613","article-title":"Transmission des filarioses. Limitation des passages des microfilaires ing\u00e9r\u00e9es vers l'h\u00e9moc\u00e8le du vecteur; interpr\u00e9tation","volume":"46","author":"Bain","year":"1971","journal-title":"Annales de Parasitologie (Paris)"},{"key":"S0031182000064751_ref072","first-page":"13","article-title":"\u00e9tude quantitative de la r\u00e9duction parasitaire stomacale chez les vecteurs de filarioses","volume":"18","author":"Prod'Hon","year":"1980","journal-title":"Cahiers O.R.S.T.O.M. s\u00e9rie Entomologie m\u00e9dicale et Parasitologie"},{"key":"S0031182000064751_ref070","doi-asserted-by":"publisher","DOI":"10.1016\/0169-2607(90)90030-D"},{"key":"S0031182000064751_ref079","doi-asserted-by":"publisher","DOI":"10.1146\/annurev.en.33.010188.002005"},{"key":"S0031182000064751_ref036","doi-asserted-by":"publisher","DOI":"10.1080\/00034983.1966.11686442"},{"key":"S0031182000064751_ref043","volume-title":"Ecology of Infectious Diseases in Natural Populations","author":"Dye","year":"1994"}],"container-title":["Parasitology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.cambridge.org\/core\/services\/aop-cambridge-core\/content\/view\/S0031182000064751","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2024,3,14]],"date-time":"2024-03-14T08:59:08Z","timestamp":1710406748000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.cambridge.org\/core\/product\/identifier\/S0031182000064751\/type\/journal_article"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1995,5]]},"references-count":93,"journal-issue":{"issue":"4","published-print":{"date-parts":[[1995,5]]}},"alternative-id":["S0031182000064751"],"URL":"https:\/\/doi.org\/10.1017\/s0031182000064751","relation":{},"ISSN":["0031-1820","1469-8161"],"issn-type":[{"value":"0031-1820","type":"print"},{"value":"1469-8161","type":"electronic"}],"subject":[],"published":{"date-parts":[[1995,5]]}}}