{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,6]],"date-time":"2026-06-06T20:25:28Z","timestamp":1780777528361,"version":"3.54.1"},"reference-count":53,"publisher":"Public Library of Science (PLoS)","issue":"11","license":[{"start":{"date-parts":[[2020,11,5]],"date-time":"2020-11-05T00:00:00Z","timestamp":1604534400000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS ONE"],"abstract":"<jats:p>\n                    We assessed the virulence and anti-trypanosomal drug sensitivity patterns of\n                    <jats:italic>Trypanosoma brucei rhodesiense<\/jats:italic>\n                    (\n                    <jats:italic>Tbr<\/jats:italic>\n                    ) isolates in the Kenya Agricultural and Livestock Research Organization-Biotechnology Research Institute (KALRO-BioRI) cryobank. Specifically, the study focused on\n                    <jats:italic>Tbr<\/jats:italic>\n                    clones originally isolated from the western Kenya\/eastern Uganda focus of human African Trypanosomiasis (HAT). Twelve (12)\n                    <jats:italic>Tbr<\/jats:italic>\n                    clones were assessed for virulence using groups(n = 10) of Swiss White Mice monitored for 60 days post infection (dpi). Based on survival time, four classes of virulence were identified: (a) very-acute: 0\u201315, (b) acute: 16\u201330, (c) sub-acute: 31\u201345 and (d) chronic: 46\u201360 dpi. Other virulence biomarkers identified included: pre-patent period (pp), parasitaemia progression, packed cell volume (PCV) and body weight changes. The test\n                    <jats:italic>Tbr<\/jats:italic>\n                    clones together with KALRO-BioRi reference drug-resistant and drug sensitive isolates were then tested for sensitivity to melarsoprol (mel B), pentamidine, diminazene aceturate and suramin, using mice groups (n = 5) treated with single doses of each drug at 24 hours post infection. Our results showed that the clones were distributed among four classes of virulence as follows: 3\/12 (very-acute), 3\/12 (acute), 2\/12 (sub-acute) and 4\/12 (chronic) isolates. Differences in survivorship, parasitaemia progression and PCV were significant (P&lt;0.001) and correlated. The isolate considered to be drug resistant at KALRO-BioRI, KETRI 2538, was confirmed to be resistant to melarsoprol, pentamidine and diminazene aceturate but it was not resistant to suramin. A cure rate of at least 80% was achieved for all test isolates with melarsoprol (1mg\/Kg and 20 mg\/kg), pentamidine (5 and 20 mg\/kg), diminazene aceturate (5 mg\/kg) and suramin (5 mg\/kg) indicating that the isolates were not resistant to any of the drugs despite the differences in virulence. This study provides evidence of variations in virulence of\n                    <jats:italic>Tbr<\/jats:italic>\n                    clones from a single HAT focus and confirms that this variations is not a significant determinant of isolate sensitivity to anti-trypanosomal drugs.\n                  <\/jats:p>","DOI":"10.1371\/journal.pone.0229060","type":"journal-article","created":{"date-parts":[[2020,11,5]],"date-time":"2020-11-05T13:33:40Z","timestamp":1604583220000},"page":"e0229060","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":10,"title":["Differential virulence of Trypanosoma brucei rhodesiense isolates does not influence the outcome of treatment with anti-trypanosomal drugs in the mouse model"],"prefix":"10.1371","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4640-5914","authenticated-orcid":true,"given":"Kariuki","family":"Ndung\u2019u","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Grace Adira","family":"Murilla","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"John Kibuthu","family":"Thuita","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Geoffrey Njuguna","family":"Ngae","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joanna Eseri","family":"Auma","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Purity Kaari","family":"Gitonga","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daniel Kahiga","family":"Thungu","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Richard Kiptum","family":"Kurgat","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Judith Kusimba","family":"Chemuliti","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Raymond Ellie","family":"Mdachi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2020,11,5]]},"reference":[{"key":"pone.0229060.ref001","doi-asserted-by":"crossref","first-page":"e968","DOI":"10.1371\/journal.pntd.0000968","article-title":"Clinical Presentation of T.b. rhodesiense Sleeping Sickness in Second Stage Patients from Tanzania and Uganda","volume":"5","author":"I Kuepfer","year":"2011","journal-title":"PLoS Negl Trop 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