Wilkinson D A, Edwards M, Shum C, Moinet M, Anderson N E, Benschop J, Nisa S
Molecular Epidemiology and Public Health Laboratory, Tāwharau Ora - School of Veterinary Sciences, Massey University, Palmerston North, New Zealand.
The Royal (Dick) School of Veterinary Studies and the Roslin Institute, University of Edinburgh, Roslin, UK.
N Z Vet J. 2024 Jan;72(1):1-9. doi: 10.1080/00480169.2023.2248930. Epub 2023 Sep 3.
To apply molecular typing to DNA isolated from historical samples to determine spp. infecting farmed and wild mammals in New Zealand.
DNA samples used in this study were extracted from urine, serum or kidney samples (or spp. cultures isolated from them) collected between 2007 and 2017 from a range of domestic and wildlife mammalian species as part of different research projects at Massey University. Samples were included in the study if they met one of three criteria: samples that tested positive with a PCR for pathogenic ; samples that tested negative by PCR but were recorded as positive to PCR for pathogenic in the previous studies; or samples that were PCR-negative in all studies but were from animals with positive agglutination titres against serogroup Tarassovi. DNA samples were typed using PCR that targeted either the or genetic loci. The resulting amplicons were sequenced and typed relative to reference sequences.
We identified several associations between mammalian hosts and strains/serovars that had not been previously reported in New Zealand. strain Pacifica was found in farmed red deer () samples, serovars Balcanica and Ballum were found in wild red deer samples, serovar Copenhageni was found in stoats () and brushtail possums (), and was found in a ferret (). Furthermore, we reconfirmed previously described associations including dairy cattle with serovars Copenhageni and Pomona and serovars Ballum, Hardjo type bovis and strain Pacifica, sheep with serovar Pomona and serovar Hardjo type bovis, brushtail possum with serovar Balcanica, farmed deer with serovar Hardjo type bovis and hedgehogs () with serovar Ballum.
This study provides an updated summary of host- associations in New Zealand and highlights the importance of molecular typing. Furthermore, strain Pacifica, which was first identified as Tarassovi using serological methods in dairy cattle in 2016, has circulated in animal communities since at least 2007 but remained undetected as serology is unable to distinguish the different genotypes.
To date, leptospirosis in New Zealand has been diagnosed with serological typing, which is deficient in typing all strains in circulation. Molecular methods are necessary to accurately type strains of spp. infecting mammals in New Zealand.
对从历史样本中分离出的DNA进行分子分型，以确定感染新西兰养殖和野生哺乳动物的钩端螺旋体种类。
本研究中使用的DNA样本是从2007年至2017年期间作为梅西大学不同研究项目一部分收集的尿液、血清或肾脏样本（或从中分离出的钩端螺旋体培养物）中提取的，这些样本来自一系列家养和野生动物哺乳动物物种。如果样本符合以下三个标准之一，则纳入本研究：经致病性钩端螺旋体PCR检测呈阳性的样本；经PCR检测呈阴性但在先前研究中记录为致病性钩端螺旋体PCR呈阳性的样本；或在所有研究中PCR均为阴性但来自对塔拉索维血清群凝集效价呈阳性的动物的样本。使用针对钩端螺旋体或致病钩端螺旋体遗传位点的PCR对DNA样本进行分型。将得到的扩增子相对于参考序列进行测序和分型。
我们确定了哺乳动物宿主与新西兰先前未报道过的钩端螺旋体菌株/血清型之间的几种关联。在养殖的马鹿（赤鹿）样本中发现了钩端螺旋体Pacifica菌株，在野生马鹿样本中发现了钩端螺旋体Balcanica和Ballum血清型，在白鼬和帚尾袋貂中发现了钩端螺旋体Copenhageni血清型，在一只雪貂中发现了致病钩端螺旋体。此外，我们再次证实了先前描述的关联，包括奶牛与钩端螺旋体Copenhageni和Pomona血清型以及钩端螺旋体Ballum、Hardjo型牛和Pacifica菌株，绵羊与钩端螺旋体Pomona血清型和钩端螺旋体Hardjo型牛血清型，帚尾袋貂与钩端螺旋体Balcanica血清型，养殖鹿与钩端螺旋体Hardjo型牛血清型以及刺猬与钩端螺旋体Ballum血清型。
本研究提供了新西兰宿主-钩端螺旋体关联的最新总结，并强调了分子分型的重要性。此外，Pacifica菌株于2016年在奶牛中首次使用血清学方法鉴定为塔拉索维钩端螺旋体，自至少2007年以来一直在动物群体中传播，但由于血清学无法区分不同基因型，一直未被检测到。
迄今为止，新西兰的钩端螺旋体病一直通过血清学分型进行诊断，而血清学分型在对所有流行菌株进行分型方面存在不足。分子方法对于准确分型感染新西兰哺乳动物的钩端螺旋体菌株是必要的。
