Figueiredo Ana M, Dashti Alejandro, Santín Mónica, Köster Pamela C, Torres Rita T, Fonseca Carlos, Mysterud Atle, Carvalho João, Sarmento Pedro, Neves Nuno, Hipólito Dário, Palmeira Josman D, Teixeira Daniela, Lima Cátia, Calero-Bernal Rafael, Carmena David
Department of Biology and CESAM, University of Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal.
Centre for Ecological and Evolutionary Synthesis, Department of Bioscience, University of Oslo, P.O Box 1066 Blindern, NO-316 Oslo, Norway.
Med Mycol. 2023 Feb 3;61(2). doi: 10.1093/mmy/myad018.
The phylum Microsporidia encompasses a diverse group of obligate, intracellular, and spore-forming organisms able to infect a wide range of animal hosts. Among them, Enterocytozoon bieneusi is the most frequently reported species in humans and animals. Little is known about the presence and epidemiology of E. bieneusi in wildlife. We investigated E. bieneusi occurrence and genetic diversity in wild and domestic mammals, through molecular-detection methods, from different regions across Portugal. A total of 756 samples were collected from 288, 242, and 226 wild carnivores, wild ungulates, and domestic animals, respectively. Overall, eight specimens were E. bieneusi-positive (1.1%, 8/756) obtained from five wild (Iberian lynx, Iberian wolf, red fox, stone marten, and wild boar) and one domestic (sheep) host. Nucleotide sequence analysis identified four genotypes of E. bieneusi, Type IV, Wildboar3, BEB6, and PtEbIX. Three of those genotypes belong to Groups 1 (Type IV and Wildboar3) and 2 (BEB6), which are known to contain genotypes capable of infecting a variety of hosts, including humans, highlighting their public health importance. PtEbIX belongs to the dog-specific Group 11. This study represents the first, largest, and most comprehensive molecular-based epidemiology survey carried out in Portugal in wild and domestic animals to date and the first worldwide identification of E. bieneusi in wolf species. Our study showed that wild carnivores and ungulates may act as reservoirs of zoonotic genotypes of E. bieneusi, establishing their role in maintaining the sylvatic cycle of this parasite while representing a potential source of infection for humans and domestic animals.
微孢子虫门包含一群多样的专性、细胞内、形成孢子的生物，能够感染广泛的动物宿主。其中，比氏肠微孢子虫是人类和动物中最常报告的物种。关于野生动物中比氏肠微孢子虫的存在情况和流行病学知之甚少。我们通过分子检测方法，对葡萄牙不同地区的野生和家养哺乳动物中比氏肠微孢子虫的发生情况和遗传多样性进行了调查。分别从288只野生食肉动物、242只野生有蹄类动物和226只家畜中总共采集了756份样本。总体而言，从5只野生宿主（伊比利亚猞猁、伊比利亚狼、赤狐、石貂和野猪）和1只家养宿主（绵羊）中获得了8份比氏肠微孢子虫阳性标本（1.1%，8/756）。核苷酸序列分析确定了比氏肠微孢子虫的4种基因型，即IV型、野猪3型、BEB6型和PtEbIX型。其中3种基因型属于第1组（IV型和野猪3型）和第2组（BEB6型），已知这两组包含能够感染包括人类在内的多种宿主的基因型，突出了它们对公共卫生的重要性。PtEbIX型属于犬特异性第11组。这项研究是葡萄牙迄今为止在野生和家养动物中开展的首次、规模最大且最全面的基于分子的流行病学调查，也是全球首次在狼物种中鉴定出比氏肠微孢子虫。我们的研究表明，野生食肉动物和有蹄类动物可能是比氏肠微孢子虫人畜共患基因型的宿主，确立了它们在维持这种寄生虫的森林循环中的作用，同时也是人类和家畜潜在的感染源。
