Department of Population Medicine, Ontario Veterinary College, University of Guelph, Guelph, ON, Canada.
Institute for Medical Information Processing, Bioinformatics and Epidemiology, Ludwig Maximilian University, Munich, Germany.
Zoonoses Public Health. 2022 Dec;69(8):944-955. doi: 10.1111/zph.12992. Epub 2022 Aug 18.
Increasing temperatures due to climate change have contributed to a northward range expansion of Ixodes scapularis ticks in Canada. These ticks harbour pathogens of public and animal health significance, including Borrelia burgdorferi and Anaplasma phagocytophilum, which cause Lyme disease and anaplasmosis, respectively, in humans, dogs and horses, and Borrelia miyamotoi, which causes a flu-like relapsing fever in humans. To address the risks associated with these vector-borne zoonotic diseases, continuous tick surveillance is advised. This study examined spatial patterns of B. burgdorferi, B. miyamotoi and A. phagocytophilum from ticks submitted through a national study on ticks of companion animals. From 1 April 2019 to 31 March 2020, we received a total of 1541 eligible submissions from 94 veterinary clinics across Canada. Individual and pooled samples of a maximum of either 5 I. scapularis, I. pacificus or I. angustus samples from the same animal and of the same life stage were screened using real-time PCR targeting genes 23S rRNA for Borrelia spp. and msp2 for A. phagocytophilum. Confirmatory testing was conducted on all 23S rRNA positive samples using a duplex assay for ospA and flaB to differentiate B. burgdorferi and B. miyamotoi, respectively. Prevalence estimates were highest (>20%) for B. burgdorferi in southwestern Manitoba, eastern Ontario, southwestern Quebec, New Brunswick and Nova Scotia. Estimates of B. miyamotoi and A. phagocytophilum were much lower (<5%), except for higher A. phagocytophilum (>5%) estimates for southern Manitoba, eastern Ontario and Prince Edward Island. Findings from this study, combined with other surveillance approaches, can be used to guide veterinary and public health approaches for ticks and tick-borne diseases.
由于气候变化导致的温度升高，导致加拿大的肩突硬蜱（Ixodes scapularis ticks）向北扩展。这些蜱虫携带具有公共卫生和动物健康重要意义的病原体，包括伯氏疏螺旋体（Borrelia burgdorferi）和嗜吞噬细胞无形体（Anaplasma phagocytophilum），它们分别在人类、狗和马中引起莱姆病和无形体病，以及米氏疏螺旋体（Borrelia miyamotoi），在人类中引起类似流感的复发性发热。为了应对与这些媒介传播的人畜共患病相关的风险，建议进行持续的蜱虫监测。本研究检查了通过全国伴侣动物蜱虫研究提交的蜱虫中伯氏疏螺旋体、米氏疏螺旋体和嗜吞噬细胞无形体的空间模式。从 2019 年 4 月 1 日至 2020 年 3 月 31 日，我们共收到来自加拿大 94 家兽医诊所的 1541 份符合条件的提交样本。来自同一动物和同一生活阶段的最大数量为 5 个肩突硬蜱、太平洋硬蜱或安氏硬蜱样本的个体和混合样本，使用针对 Borrelia spp. 的 23S rRNA 基因和针对嗜吞噬细胞无形体的 msp2 基因的实时 PCR 进行筛选。对所有 23S rRNA 阳性样本进行 ospA 和 flaB 的双重检测，以分别区分伯氏疏螺旋体和米氏疏螺旋体。曼尼托巴省西南部、安大略省东部、魁北克省西南部、新不伦瑞克省和新斯科舍省的伯氏疏螺旋体的流行率估计值最高（>20%）。米氏疏螺旋体和嗜吞噬细胞无形体的估计值要低得多（<5%），但曼尼托巴省南部、安大略省东部和爱德华王子岛的嗜吞噬细胞无形体的估计值较高（>5%）。本研究的结果，结合其他监测方法，可以用于指导兽医和公共卫生部门针对蜱虫和蜱传疾病的方法。
