{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,13]],"date-time":"2026-03-13T17:23:37Z","timestamp":1773422617643,"version":"3.50.1"},"reference-count":14,"publisher":"Cambridge University Press (CUP)","issue":"2","license":[{"start":{"date-parts":[[2001,7,31]],"date-time":"2001-07-31T00:00:00Z","timestamp":996537600000},"content-version":"unspecified","delay-in-days":180,"URL":"https:\/\/www.cambridge.org\/core\/terms"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Parasitology"],"published-print":{"date-parts":[[2001,2]]},"abstract":"<jats:p>A model is presented which describes the aggregation of female <jats:italic>Onchocerca volvulus<\/jats:italic> in nodules and their distribution in the human population. The basic model is based on a single parameter, the formation probability <jats:italic>q<\/jats:italic>, which represents the probability with which incoming larvae form a new nodule. This parameter describes parasite behaviour which cannot easily be recognized in available data without modelling. The estimate for the average formation probability of <jats:italic>\u03bc<\/jats:italic><jats:sub><jats:italic>q<\/jats:italic><\/jats:sub> = 0.39 suggests an attraction of the invading infective larvae to already existing nodules or resident worms with probability 0.61. No significant difference in <jats:italic>\u03bc<\/jats:italic><jats:sub><jats:italic>q<\/jats:italic><\/jats:sub> was found between the forest and savanna parasite strains. The model can be used inversely to estimate the worm burden of persons from palpation data. The observed variance in the number of nodules per person requires the assumption of a variance-increasing mechanism which was implemented by heterogeneity within the host population (extended model with 2 parameters). Possible reasons for this heterogeneity are presented and its implications concerning the reproductive biology of the parasite are discussed.<\/jats:p>","DOI":"10.1017\/s0031182001008186","type":"journal-article","created":{"date-parts":[[2002,10,30]],"date-time":"2002-10-30T15:58:42Z","timestamp":1035993522000},"page":"193-201","source":"Crossref","is-referenced-by-count":19,"title":["A stochastic model for the aggregation of <i>Onchocerca volvulus <\/i>in nodules"],"prefix":"10.1017","volume":"123","author":[{"given":"H.\u00a0P.","family":"DUERR","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"K.","family":"DIETZ","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"D.\u00a0W.","family":"B\u00dcTTNER","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"H.","family":"SCHULZ-KEY","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"56","published-online":{"date-parts":[[2001,7,31]]},"reference":[{"key":"S0031182001008186_ref014","unstructured":"WIMMER, G. & ALTMANN, G. (1999). Thesaurus of Univariate Discrete Probability Distributions . Stamm, Essen, Germany."},{"key":"S0031182001008186_ref012","unstructured":"SCHULZ-KEY, H. , ALBIEZ, E.\u00a0J. & B\u00dcTTNER, D.\u00a0W. (1977). Isolation of adult Onchocerca volvulus from nodules. Tropenmedizin und Parasitologie 28, 428\u2013430."},{"key":"S0031182001008186_ref011","unstructured":"SCHULZ-KEY, H. & ALBIEZ, A.\u00a0J. (1977). Worm burden of Onchocerca volvulus in a hyperendemic village of the rain-forest in West Africa. Tropenmedizin und Parasitologie 28, 409\u2013560."},{"key":"S0031182001008186_ref003","unstructured":"ALBIEZ, E.\u00a0J. , B\u00dcTTNER, D.\u00a0W. & DUKE, B.\u00a0O.\u00a0L. (1988). Diagnosis and extirpation of nodules in human onchocerciasis. Tropical Medicine and Parasitology 39 (Suppl.\u00a0IV), 331\u2013346."},{"key":"S0031182001008186_ref009","doi-asserted-by":"crossref","unstructured":"PLENGE-B\u00d6NIG, A. , KR\u00d6MER, M. & B\u00dcTTNER, D.\u00a0W. (1995). Light and electron microscopy studies on Onchocerca jakutensis and O. flexuosa of red deer show different host\u2013parasite interactions. Parasitology Research 81, 66\u201373.","DOI":"10.1007\/BF00932419"},{"key":"S0031182001008186_ref002","unstructured":"ALBIEZ, E.\u00a0J. , B\u00dcTTNER, D.\u00a0W. & SCHULZ-KEY, H. (1984). Studies on nodules and adult Onchocerca volvulus during a nodulectomy trial in hyperendemic villages in Liberia and Upper Volta. II. Comparison of the macrofilaria population in adult nodule carriers. Tropenmedizin und Parasitologie 35, 163\u2013166."},{"key":"S0031182001008186_ref013","doi-asserted-by":"publisher","DOI":"10.1016\/0169-4758(86)90138-9"},{"key":"S0031182001008186_ref004","doi-asserted-by":"publisher","DOI":"10.1051\/parasite\/1981565503"},{"key":"S0031182001008186_ref001","unstructured":"ALBIEZ, E.\u00a0J. (1983). Studies on nodules and adult Onchocerca volvulus during a nodulectomy trial in hyperendemic villages in Liberia and Upper Volta.\u00a0I.\u00a0Palpable and impalpable onchocercomata. Tropenmedizin und Parasitologie 34, 54\u201360."},{"key":"S0031182001008186_ref005","unstructured":"B\u00dcTTNER, D.\u00a0W. , ALBIEZ, E.\u00a0J. , VON ESSEN, J. & ERICHSEN, J. (1988). Histological examination of adult Onchocerca volvulus and comparison with the collagenase technique. Tropical Medicine and Parasitology 39 (Suppl.\u00a0IV), 390\u2013417."},{"key":"S0031182001008186_ref007","doi-asserted-by":"publisher","DOI":"10.1016\/S0025-5564(00)00014-6"},{"key":"S0031182001008186_ref006","doi-asserted-by":"publisher","DOI":"10.4269\/ajtmh.1982.31.267"},{"key":"S0031182001008186_ref008","unstructured":"DUKE, B.\u00a0O.\u00a0L. (1993). The population dynamics of Onchocerca volvulus in the human host. Tropical Medicine and Parasitology 44, 61\u201368."},{"key":"S0031182001008186_ref010","unstructured":"PRESS, W.\u00a0H. , TEUKOLSKY, S.\u00a0A. , VETTERLING, W.\u00a0T. & FLANNERY, B.\u00a0P. (1992). Numerical Recipes in C, 2nd Edn. Cambridge University Press, Cambridge."}],"container-title":["Parasitology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.cambridge.org\/core\/services\/aop-cambridge-core\/content\/view\/S0031182001008186","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2019,4,2]],"date-time":"2019-04-02T19:30:25Z","timestamp":1554233425000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.cambridge.org\/core\/product\/identifier\/S0031182001008186\/type\/journal_article"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2001,2]]},"references-count":14,"journal-issue":{"issue":"2","published-print":{"date-parts":[[2001,8]]}},"alternative-id":["S0031182001008186"],"URL":"https:\/\/doi.org\/10.1017\/s0031182001008186","relation":{},"ISSN":["0031-1820","1469-8161"],"issn-type":[{"value":"0031-1820","type":"print"},{"value":"1469-8161","type":"electronic"}],"subject":[],"published":{"date-parts":[[2001,2]]}}}