Laboratory of Veterinary Bacteriology, Biomedical Institute, Fluminense Federal University, Niterói, Rio de Janeiro, Brazil.
R3 Animal Association, Florianópolis, SC 88061-500, Brazil.
Res Vet Sci. 2023 Feb;155:62-68. doi: 10.1016/j.rvsc.2022.12.012. Epub 2023 Jan 5.
Leptospirosis is a bacterial disease caused by the infection of pathogenic strains of the genus Leptospira, endemic in tropical and subtropical regions. Although well documented in terrestrial animals and humans, little information is available on its distribution and impact on marine animals. Despite clinical manifestations that may occur, the occurrence of carriers was suggested in some species. Nevertheless, there are few studies regarding the infection by Leptospira sp. in marine mammals. In this context, and considering the One Health approach, the present aimed to investigate pinnipeds' role as Leptospira sp. carriers. Kidneys of 47 pinnipeds of two species, Arctocephalus australis (n = 40) and Arctocephalus tropicalis (n = 7) were collected. DNA was extracted and the diagnosis was performed through LipL32-PCR and genetic characterization based on secY gene sequencing. Phylogenetic analysis and haplotype networks were constructed. Pathogenic Leptospira sp. DNA was detected in 31.9% (15/47) of the tested pinnipeds. It was possible to amplify and sequence eight strains (6 for A. australis, 2 for A. tropicalis), all identified as L. interrogans, with high similarity with sequences from Icterohaemorrhagiae serogroup. Phylogenetic analysis revealed sequences from the present study grouped in species-specific unique clusters, but very close to others from humans, wild animals, and domestic animals. We demonstrate that pinnipeds could act as carriers, and play an important role in leptospirosis dynamics.
钩端螺旋体病是一种由钩端螺旋体属的致病性菌株感染引起的细菌性疾病，流行于热带和亚热带地区。尽管在陆生动物和人类中有很好的记录，但关于其在海洋动物中的分布和影响的信息很少。尽管可能出现临床表现，但一些物种被认为存在带菌者。然而，关于海洋哺乳动物感染钩端螺旋体的研究很少。在这种情况下，并考虑到“One Health”方法，本研究旨在调查鳍足类动物作为钩端螺旋体属携带者的作用。采集了两种鳍足类动物（南澳毛皮海狮，n=40；南海狮，n=7）的 47 只鳍足类动物的肾脏。提取 DNA 并通过 LipL32-PCR 进行诊断，并基于 secY 基因测序进行遗传特征分析。构建了系统发育分析和单倍型网络。在 47 只检测的鳍足类动物中，有 31.9%（15/47）检测到致病性钩端螺旋体属 DNA。能够扩增和测序 8 株（A. australis 有 6 株，A. tropicalis 有 2 株），均鉴定为问号钩端螺旋体，与 Icterohaemorrhagiae 血清群的序列高度相似。系统发育分析显示，本研究中的序列在种特异性的独特聚类中分组，但与来自人类、野生动物和家畜的其他序列非常接近。我们证明了鳍足类动物可能作为携带者，在钩端螺旋体病的动态中发挥重要作用。
