Duncan Colleen G, Tiller Rebekah, Mathis Demetrius, Stoddard Robyn, Kersh Gilbert J, Dickerson Bobette, Gelatt Tom
Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO (Duncan).
Bacterial Special Pathogens (Tiller, Mathis, Stoddard) Branches of the Centers for Disease Control and Prevention, Atlanta, GA.
J Vet Diagn Invest. 2014 Jul;26(4):507-512. doi: 10.1177/1040638714532647.
Brucella species infect a wide range of hosts with a broad spectrum of clinical manifestations. In mammals, one of the most significant consequences of Brucella infection is reproductive failure. There is evidence of Brucella exposure in many species of marine mammals, but the outcome of infection is often challenging to determine. The eastern Pacific stock of northern fur seals (NFSs, Callorhinus ursinus) has declined significantly, spawning research into potential causes for this trend, including investigation into reproductive health. The objective of the current study was to determine if NFSs on St. Paul Island, Alaska have evidence of Brucella exposure or infection. Archived DNA extracted from placentas ( n = 119) and serum ( n = 40) samples were available for testing by insertion sequence (IS) 711 polymerase chain reaction (PCR) and the Brucella microagglutination test (BMAT), respectively. As well, placental tissue was available for histologic examination. Six (5%) placentas were positive by PCR, and a single animal had severe placentitis. Multilocus variable number tandem repeat analysis profiles were highly clustered and closely related to other Brucella pinnipedialis isolates. A single animal was positive on BMAT, and 12 animals had titers within the borderline range; 1 borderline animal was positive by PCR on serum. The findings suggest that NFSs on the Pribilof Islands are exposed to Brucella and that the organism has the ability to cause severe placental disease. Given the population trend of the NFS, and the zoonotic nature of this pathogen, further investigation into the epidemiology of this disease is recommended.
布鲁氏菌属感染多种宿主，临床表现广泛。在哺乳动物中，布鲁氏菌感染最显著的后果之一是繁殖失败。有证据表明许多海洋哺乳动物物种都接触过布鲁氏菌，但感染的结果往往难以确定。北太平洋海狗（NFSs，Callorhinus ursinus）的东太平洋种群数量大幅下降，引发了对这一趋势潜在原因的研究，包括对生殖健康的调查。本研究的目的是确定阿拉斯加圣保罗岛上的北太平洋海狗是否有接触或感染布鲁氏菌的证据。分别从胎盘（n = 119）和血清（n = 40）样本中提取的存档DNA可用于通过插入序列（IS）711聚合酶链反应（PCR）和布鲁氏菌微凝集试验（BMAT）进行检测。此外，胎盘组织可用于组织学检查。6个（5%）胎盘PCR检测呈阳性，1只动物患有严重胎盘炎。多位点可变数目串联重复分析图谱高度聚集，且与其他海狗布鲁氏菌分离株密切相关。1只动物BMAT检测呈阳性，12只动物的滴度处于临界范围内；1只临界动物血清PCR检测呈阳性。研究结果表明，普里比洛夫群岛上的北太平洋海狗接触过布鲁氏菌，且该病原体有能力导致严重的胎盘疾病。鉴于北太平洋海狗的种群趋势以及该病原体的人畜共患性质，建议进一步调查该疾病的流行病学情况。
