{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T02:36:44Z","timestamp":1792723004347,"version":"4.5.0"},"reference-count":32,"publisher":"Cambridge University Press (CUP)","issue":"2","license":[{"start":{"date-parts":[[2009,4,6]],"date-time":"2009-04-06T00:00:00Z","timestamp":1238976000000},"content-version":"unspecified","delay-in-days":11510,"URL":"https:\/\/www.cambridge.org\/core\/terms"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Parasitology"],"published-print":{"date-parts":[[1977,10]]},"abstract":"<jats:p>Relapse of infection after drug treatment of trypanosome infections under conditions precluding re-infection has usually been ascribed to drug resistance on the part of the parasite or to under-dosage of the drug. With <jats:italic>Trypanosoma brucei<\/jats:italic> infection in mice we have obtained evidence of another type of relapse. In infections resulting from the inoculation of 1 \u00d7 10<jats:sup>5<\/jats:sup> trypanosomes, derived from a stabilate <jats:italic>T. brucei<\/jats:italic> TREU 667, treatment with diminazene aceturate (Berenil) at 40 mg\/kg at either 3 or 7 days after infection elicited a permanent cure. If, however, treatment was delayed later than 14 days after infection, then all the mice relapsed. These relapses generally occurred between 20 and 50 days after treatment, but some mice remained aparasitaemic for up to 60 days. The relapsed infections were apparently not due to the survival of \u2018drug-resistant\u2019 trypanosomes, as infections derived from a stabilate isolated from a relapsed Berenil-treated mouse were also permanently cured with Berenil if treated 3 days after infection; however, if treatment was delayed until 21 days post-infection, all the mice relapsed. The cause of relapse was not related to the number of parasites inoculated, as infection resulting from initial inocula of 1 \u00d7 10<jats:sup>5<\/jats:sup> to 1 \u00d7 10<jats:sup>8<\/jats:sup> trypanosomes were all cured if treated at 3 days after infection, and all eventually relapsed if treatment was delayed until day 21. This type of relapse phenomenon was not confined to <jats:italic>T. brucei<\/jats:italic> TREU 667 but also occurred with 5 other stabi-lates of <jats:italic>T. brucei<\/jats:italic> after Berenil treatment. Treatment of T. brucei TREU 667 infections with Ethidium and Prothidium at dose levels of 7.5 and 10 mg\/kg respectively was also followed by relapse if treatment was delayed for 3 weeks after infection. The possible causes of relapse under these conditions, and its implications in the study of the natural disease, are discussed.<\/jats:p>","DOI":"10.1017\/s0031182000062284","type":"journal-article","created":{"date-parts":[[2009,6,5]],"date-time":"2009-06-05T16:54:22Z","timestamp":1244220862000},"page":"143-153","source":"Crossref","is-referenced-by-count":96,"title":["The relationship between duration of infection with <i>Trypanosoma brucei<\/i> in mice and the efficacy of chemotherapy"],"prefix":"10.1017","volume":"75","author":[{"given":"F. W.","family":"Jennings","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"D. D.","family":"Whitelaw","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"G. 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Ph.D. thesis, University of Glasgow. Reviewed by E. M. Lourie, Tropical Diseases Bulletin 42, 704\u20139."},{"key":"S0031182000062284_ref020","doi-asserted-by":"publisher","DOI":"10.1016\/0035-9203(71)90088-5"},{"key":"S0031182000062284_ref007","unstructured":"Fink E. & Dann O. (1974). The specific curative and prophylactic activity of diamidines against T. rhodesiense and T. congolense. In Control Programs for Trypanosomes and their Vectors. Revue d'\u00e9levage et de m\u00e9dicine veterinaire de pays tropicaux pp. 297\u2013300. Office International des Epizooties."},{"key":"S0031182000062284_ref012","first-page":"95","volume-title":"Techniques with Trypanosomes","author":"Lumsden","year":"1973"},{"key":"S0031182000062284_ref015","first-page":"282","article-title":"Additional notes on the aparasitaemic interval following subcurative treatment with diminazene of T. vivax infection in cattle","volume":"67","author":"Maclennan","year":"1973","journal-title":"Transactions of the Royal Society of Tropical Medicine and Hygiene"},{"key":"S0031182000062284_ref014","doi-asserted-by":"publisher","DOI":"10.1007\/BF02359582"},{"key":"S0031182000062284_ref018","doi-asserted-by":"publisher","DOI":"10.1016\/S0140-6736(70)90257-6"},{"key":"S0031182000062284_ref019","doi-asserted-by":"publisher","DOI":"10.1016\/0035-9203(71)90087-3"},{"key":"S0031182000062284_ref025","doi-asserted-by":"publisher","DOI":"10.1016\/0035-9203(70)90007-6"},{"key":"S0031182000062284_ref016","doi-asserted-by":"publisher","DOI":"10.1007\/BF02356438"},{"key":"S0031182000062284_ref022","first-page":"315","article-title":"Un stade leishmaniaoide dans revolution du Tr. 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