Sydney School of Veterinary Science, Faculty of Science, the University of Sydney, New South Wales, Australia.
Sydney School of Veterinary Science, Faculty of Science, the University of Sydney, New South Wales, Australia.
Acta Trop. 2020 May;205:105416. doi: 10.1016/j.actatropica.2020.105416. Epub 2020 Feb 24.
Q fever is considered one of the most important zoonoses in Australia. Whilst ruminants are the primary reservoirs for Coxiella burnetii, and the major source of human infection, human cases have also been reported following contact with pet dogs and cats. This study aimed to estimate the prevalence of seropositivity to, and bacterial shedding of, C. burnetii by pet dogs and cats in a region with a high human Q fever incidence and explore risk factors for C. burnetii exposure. Samples (serum, whole blood, reproductive tissue, reproductive swabs) and questionnaires (completed by the pet's owner) were collected from dogs and cats from eight communities across remote New South Wales (NSW), Australia. Overall 86/330 dogs (26.1%, 95% CI 21.3-30.8%) and 19/145 cats (13.1%, 95% CI 7.6-18.6%) were seropositive to C. burnetii. Seroprevalence varied significantly between communities and was highest in communities within 150 km of a 2015 human Q fever outbreak. Feeding raw kangaroo was identified as a risk factor for seropositivity (adjusted OR 3.37, 95% CI 1.21-9.43). Coxiella burnetii DNA was not detected from any dog or cat whole blood, reproductive tissue or vaginal/preputial swab using qPCR targeting the IS1111 and com1 genes. Our findings suggest that companion animals are frequently exposed to C. burnetii in western NSW. Geographical variation in C. burnetii seroprevalence amongst companion animals - which corresponds with a human Q fever outbreak - suggests a shared environmental source of infection is likely with important consequences for public and animal health. The lack of detection of C. burnetii DNA from healthy companion animals suggests that pet dogs and cats are not an important reservoir for human Q fever infection outside a narrow periparturient window.
Q 热被认为是澳大利亚最重要的人畜共患病之一。虽然反刍动物是科氏立克次体的主要宿主，也是人类感染的主要来源，但在接触宠物狗和猫后，也有人类感染病例的报告。本研究旨在估计在 Q 热高发地区宠物狗和猫感染科氏立克次体的血清阳性率和细菌脱落率，并探讨科氏立克次体暴露的危险因素。从澳大利亚新南威尔士州偏远地区的 8 个社区采集了狗和猫的样本（血清、全血、生殖组织、生殖拭子）和调查问卷（由宠物主人填写）。共有 330 只狗中的 86 只（26.1%，95%置信区间 21.3-30.8%）和 145 只猫中的 19 只（13.1%，95%置信区间 7.6-18.6%）对科氏立克次体呈血清阳性。社区之间的血清阳性率差异显著，在距离 2015 年人类 Q 热爆发地点 150 公里范围内的社区中，血清阳性率最高。食用生袋鼠被确定为血清阳性的危险因素（调整后的 OR 3.37，95%置信区间 1.21-9.43）。使用靶向 IS1111 和 com1 基因的 qPCR 未从任何狗或猫的全血、生殖组织或阴道/包皮拭子中检测到科氏立克次体 DNA。我们的研究结果表明，在新南威尔士州西部，宠物狗和猫经常接触科氏立克次体。在科氏立克次体感染的伴侣动物中，地理变异与人类 Q 热爆发相对应，这表明感染存在共同的环境来源，这对公共卫生和动物健康具有重要意义。从健康的伴侣动物中未检测到科氏立克次体 DNA 表明，在狭窄的围产期窗口之外，宠物狗和猫不是人类 Q 热感染的重要储存库。
