眼病是一种人畜共患的眼病,主要影响世界不同地区的家养和野生鸟类。然而,与其在家畜中的流行病学有关的方面尚不完全清楚。在本研究中,47番鸭(Cairinamoschata),8只野鸭(Anasplatyrhynchosplatyrhynchos)和6只非洲鹅(Ansercygnoides),自由生活在贝洛奥里藏特的城市湖泊中,米纳斯吉拉斯州,巴西,进行眼吸虫感染评估。动物被手动控制,结膜囊和硝化膜通过直接眼科检查(DOE)进行评估,其中侥幸负担是通过半定量尺度来估计的。此外,结膜囊灌洗(CSL)技术用于寻找寄生虫卵。如果可能,小心地取出检测到的吸虫以进行分类鉴定。为了表征寄生虫-宿主-环境系统,疟疾收集是在当地进行的,并对收集的中间寄主软体动物(Melanoidestuberculata)进行了幼虫梅毒感染评估。此外,野生脊椎动物在当地被发现死亡,包括一个普通的galeata(Gallinulagaleata)和两个capybaras(Hydrochoerushydrochaeris),进行尸检以寻找眼睛吸虫。对从宿主获得的发育阶段的样品进行形态学和分子研究(扩增和测序Nad-1基因的部分区域)。在DOE中,67%(4/6)的人证实了眼睛吸虫的存在,31%(15/47)和25%(2/8)的鹅,番鸭和野鸭,分别。在大多数情况下,鸟类表现出轻度寄生(1-5只吸虫),没有明显的眼睛损伤,描述亚临床感染的特征。只有一只鹅,有很高的侥幸负担(20只吸虫),可以通过CSL获得卵子。关于疟疾调查,73/4545(1.6%)被评估的结核分枝杆菌标本被发现感染了巨大的尾蚴,与Philophymidae家族的代表兼容。此外,从在湖中发现的G.galeata标本中发现了147只吸虫。在这项研究中评估了从不同宿主获得的寄生虫的形态学和分子研究,从而能够鉴定出Philthemusgralli,一种原产于亚洲并在美洲引进的物种。中间宿主的广泛分布以及家养和野生水库参与寄生虫传播链等因素可能有利于寄生虫从野生鸟类溢出到家养鸟类。此外,城市水体中P.gralli生命周期的发生是对这种人畜共患眼寄生虫的人类病例的警报。
Philophthalmosis is a zoonotic ocular disease that affects mainly domestic and wild avian species in different parts of the world. However, aspects related to its epizoology in domestic animals are not completely known. In the present
study, 47 Muscovy duck (Cairina moschata), 8 mallards (Anas platyrhynchos platyrhynchos) and 6 African geese (Anser cygnoides), free-living in an urban lake in Belo Horizonte, Minas Gerais, Brazil, were evaluated for eye fluke infection. The animals were manually contained, and the conjunctival sac and nictitating membrane were evaluated by direct ophthalmic examination (DOE), in which the fluke burden was estimated by a semiquantitative scale. Moreover, the conjunctival sac lavage (CSL) technique was applied for the search of parasite eggs. When possible, the detected trematodes were carefully removed for fixed for taxonomic identification. In order to characterize the parasite-host-environmental system, malacological collections were performed at the locality, and the collected intermediate host mollusks (Melanoides tuberculata) were evaluated for infection with larval philophthalmids. In addition, wild vertebrates found dead in the locality, including one common gallinule (Gallinula galeata) and two capybaras (Hydrochoerus hydrochaeris), were necropsied for the search of eye flukes. Samples from the developmental stages obtained from the hosts were subjected to morphological and molecular studies (amplification and sequencing of a partial region of the Nad-1 gene). In the DOE, the presence of eye flukes was verified in 67% (4/6), 31% (15/47) and 25% (2/8) in geese, Muscovy ducks and mallards, respectively. In most cases, the birds showed mild parasitism (1-5 trematodes), with no apparent eye damage, characterizing a subclinical infection. In only one goose, which had a high fluke burden (20 trematodes), it was possible to obtain eggs by CSL. Regarding the malacological survey, 73/4545 (1.6%) specimens of M. tuberculata evaluated were found infected with megalurous cercariae, compatible with representatives of the family Philophthalmidae. Additionally, 147 flukes were recovered from a specimen of G. galeata found dead at the lake. The morphological and molecular
study of parasites obtained from different hosts evaluated in this
study enabled the identification of Philophthalmus gralli, a species native from Asia and introduced in the Americas. Factors such as the wide distribution of the intermediate host and the participation of domestic and wild reservoirs in the parasite transmission chain may favor the occurrence of parasite spillover from wild to domestic birds. Furthermore, the occurrence of the life cycle of P. gralli in an urban waterbody serves as an alert to the possibility of human cases of this zoonotic eye parasite.