OCCURRENCE OF FILARID PARASITES IN HOUSEHOLD AND SHELTERED DOGS IN THE CITY OF JOINVILLE – SANTA CATARINA, BRAZIL

Abstract Parasites from the Filariidae family are among the nematodes that can infest dogs. Some may be apathogenic, such as Acanthocheilonema reconditum, and others such as Dirofilaria immitis are potentially zoonotic and may lead dogs to death. Thus, the aim of this study was to perform a survey on filarid infection in dogs with a fixed domicile and wandering dogs temporarily sheltered in the city of Joinville, SC, Brazil. Blood samples from 429 animals were collected from 2015 to 2017 and submitted to screening for microfilariae and/or D. immitis antigens. Our results revealed that twenty-four samples (5.6%) displayed A. reconditum microfilariae and three samples (0.7%) were positive for D. immitis, totaling 27 (6.3%) positive animals for filarid parasites. Additionally, A. reconditum was more prevalent in dogs from shelters, whereas the three D. immitis positive samples were from household dogs that displayed no clinical signs of the presence of parasites. The occurrence of these parasites in dogs from Joinville indicates the importance of differential diagnosis of microfilaria species for the correct clinical management of infected dogs. Our epidemiological information may help the medical and veterinary community of the region regarding clinical suspicion of canine and human heartworm disease, as well as guide preventive actions targeting public and animal health.

摘要 丝虫科（Filariidae）寄生虫是可寄生于犬类的线虫类群之一。部分种类无致病性，如隐秘棘唇线虫（Acanthocheilonema reconditum）；而另一些种类如犬恶丝虫（Dirofilaria immitis）则具有潜在人兽共患性，可导致犬只死亡。因此本研究旨在对巴西圣卡塔琳娜州约恩维利市的定居家养犬及临时收容的流浪犬开展丝虫感染情况调查。本研究于2015至2017年间收集了429只受试动物的血液样本，用于微丝蚴（microfilariae）及/或犬恶丝虫抗原的筛查检测。结果显示，24份样本（5.6%）呈隐秘棘唇线虫微丝蚴阳性，3份样本（0.7%）犬恶丝虫检测呈阳性，总计27份样本（6.3%）的受试犬只呈丝虫寄生虫感染阳性。此外，隐秘棘唇线虫感染在收容所犬只中更为高发，而3份犬恶丝虫阳性样本均来自无任何寄生虫感染临床症状的家养犬。约恩维利市犬只中此类寄生虫的检出情况，提示对微丝蚴种类进行鉴别诊断对于感染犬只的精准临床管理具有重要意义。本研究的流行病学数据可为当地医疗与兽医界针对犬类及人类心丝虫病的临床疑似诊疗提供参考，同时可为面向公共卫生与动物健康的预防性干预措施提供指导方向。