{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,9]],"date-time":"2026-07-09T14:13:08Z","timestamp":1783606388867,"version":"3.55.0"},"reference-count":67,"publisher":"Public Library of Science (PLoS)","issue":"1","license":[{"start":{"date-parts":[[2023,1,31]],"date-time":"2023-01-31T00:00:00Z","timestamp":1675123200000},"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>Human brucellosis diagnosis has been a challenge in <jats:italic>Brucella<\/jats:italic>-endemic areas. In Kenya, diagnosis is usually carried out using Febrile Brucella Antigen agglutination test (FBAT) whose performance is not well documented. This paper reports on the sensitivity and specificity of the FBAT used for brucellosis diagnosis on blood samples\/serum collected in three healthcare facilities in Baringo County, Kenya, and on <jats:italic>Brucella<\/jats:italic> species present in the study area. The FBAT test results at the hospitals were used to guide patient management. Patients who visited the hospital\u2019s laboratory with a clinician\u2019s request for brucellosis testing also filled a questionnaire to assess knowledge and attitudes associated with transmission of the disease in the study area. The remaining serum samples were tested again using FBAT and Rose Bengal Plate Test (RBPT) within a month of blood collection at the University Nairobi Laboratory. The two rapid tests were then compared, with respect to brucellosis diagnostic sensitivity and specificity. To identify infecting <jats:italic>Brucella<\/jats:italic> species, a proportion 43% (71\/166) of the blood clots were analyzed by multiplex polymerase chain reaction (PCR) using specific primers for <jats:italic>B<\/jats:italic>. <jats:italic>abortus<\/jats:italic>, <jats:italic>B<\/jats:italic>. <jats:italic>melitensis<\/jats:italic>, <jats:italic>B<\/jats:italic>. <jats:italic>ovis<\/jats:italic> and <jats:italic>B<\/jats:italic>. <jats:italic>suis<\/jats:italic>. Out of 166 serum samples tested, 26.5% (44\/166) were positive using FBAT and 10.2% (17\/166) positive using RBPT. The sensitivity and specificity of FBAT compared to RBPT was 76.47% and 71.19%, respectively while the positive and negative predictive values were 29.55% and 96.72%, respectively. The FBAT showed higher positivity then RBPT. The difference in sensitivity and specificity of FBAT and RBPTs was relatively low. The high FBAT positivity rate would be indication of misdiagnosis; this would lead to incorrect treatment. <jats:italic>Brucella abortus<\/jats:italic> was detected from 9.9% (7\/71) of the blood clots tested; no other <jats:italic>Brucella<\/jats:italic> species were detected. Thus human brucellosis, in Baringo was mainly caused by <jats:italic>B<\/jats:italic>. <jats:italic>abortus<\/jats:italic>.<\/jats:p>","DOI":"10.1371\/journal.pone.0269831","type":"journal-article","created":{"date-parts":[[2023,1,31]],"date-time":"2023-01-31T18:30:38Z","timestamp":1675189838000},"page":"e0269831","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":10,"title":["Human brucellosis in Baringo County, Kenya: Evaluating the diagnostic kits used and identifying infecting Brucella species"],"prefix":"10.1371","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6260-9346","authenticated-orcid":true,"given":"Nelly M. A.","family":"Waringa","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lilian W.","family":"Waiboci","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8573-5345","authenticated-orcid":true,"given":"Lilly","family":"Bebora","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Peter W.","family":"Kinyanjui","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Philemon","family":"Kosgei","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6605-988X","authenticated-orcid":true,"given":"Stella","family":"Kiambi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eric","family":"Osoro","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2023,1,31]]},"reference":[{"key":"pone.0269831.ref001","first-page":"3","article-title":"Brucellosis as a world problem","volume":"56","author":"Z Matyas","year":"1984","journal-title":"Developments in biological standardization"},{"key":"pone.0269831.ref002","first-page":"61222","volume-title":"Control of animal brucellosis, The most effective tool to prevent human brucellosis. 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