Maloney Jenny, Newsome Anthony, Huang Junjun, Kirby Jordona, Kranz Melissa, Wateska Angela, Dunlap Brett, Yabsley Michael J, Dunn John R, Jones Timothy F, Moncayo Abelardo C
Vector-borne Diseases Section, Tennessee Department of Health, Nashville, Tennessee 37216, USA.
J Parasitol. 2010 Apr;96(2):353-8. doi: 10.1645/GE-2312.1.
Trypanosoma cruzi is the etiologic agent of Chagas' disease. Autochthonous human and canine transmission of T. cruzi has been documented in Tennessee, but little is known about its ecology, including the prevalence of T. cruzi among wildlife in Tennessee. Serum samples from 706 raccoons (Procyon lotor) from 10 counties in the Ridge and Valley and Blue Ridge Mountains ecoregions of eastern Tennessee were tested for antibodies reactive with T. cruzi using the indirect fluorescent antibody assay. Two hundred six (29.2%) samples were seropositive, with 9 counties yielding positive samples (range 14.6-63.6%). Significantly more raccoons from rural habitats (35.1%) were found positive for T. cruzi exposure than were those from suburban habitats (23.1%, P < 0.001). Land cover class was not associated with seropositivity status (P = 0.441), even though deciduous forest was the most common site from where raccoons were trapped and the most common site of positive raccoons in rural areas (42%). Interestingly, age was positively associated with seropositivity. Raccoons older than 1 yr (adults) were 40.1% seropositive compared to 12.2% of those less than 1 yr (juveniles; P < 0.001). Female adults were significantly more likely to be exposed to T. cruzi than were male adult raccoons (P < 0.001). No significant seroprevalence difference was seen among male and female juveniles. This study contributes to understanding the dynamics of T. cruzi exposure within raccoon populations in Tennessee. The importance of habitat (rural vs. suburban) and microhabitat (dens) in risk of exposure to these populations is also discussed.
克氏锥虫是恰加斯病的病原体。在田纳西州已记录到克氏锥虫在人类和犬类中的本地传播，但对其生态了解甚少，包括田纳西州野生动物中克氏锥虫的流行情况。使用间接荧光抗体检测法，对来自田纳西州东部岭谷和蓝岭山脉生态区10个县的706只浣熊（北美浣熊）的血清样本进行了与克氏锥虫反应的抗体检测。206份（29.2%）样本血清呈阳性，9个县有阳性样本（范围为14.6%-63.6%）。发现来自农村栖息地的浣熊（35.1%）克氏锥虫暴露阳性率显著高于来自郊区栖息地的浣熊（23.1%，P<0.001）。土地覆盖类别与血清阳性状态无关（P = 0.441），尽管落叶林是捕获浣熊最常见的地点，也是农村地区阳性浣熊最常见的地点（42%）。有趣的是，年龄与血清阳性呈正相关。1岁以上（成年）的浣熊血清阳性率为40.1%，而1岁以下（幼年）的浣熊血清阳性率为12.2%（P<0.001）。成年雌性浣熊比成年雄性浣熊更易感染克氏锥虫（P<0.001）。在幼年雄性和雌性浣熊之间未观察到显著的血清阳性率差异。本研究有助于了解田纳西州浣熊种群中克氏锥虫暴露的动态情况。还讨论了栖息地（农村与郊区）和微栖息地（巢穴）对这些种群暴露风险的重要性。
