Gummow B, Tan Rhh, Joice R K, Burgess G, Picard J
College of Public Health, Medical and Veterinary Sciences, James Cook University, Townsville, Queensland, Australia.
Department of Production Animal Studies, Faculty of Veterinary Science, University of Pretoria, Pretoria, South Africa.
Aust Vet J. 2018 Jul;96(7):243-251. doi: 10.1111/avj.12711.
To investigate the seroprevalence and associated risk factors of alphaviruses (Ross River virus (RRV), Barmah Forest virus (BFV) and Whataroa virus (WHAV)) in northern Queensland horses.
A cross-sectional study of alphavirus antibodies in horses (n = 287) from 147 properties in northern Queensland from September 2013 to June 2014 was conducted. Owners of sampled horses were interviewed on potential risk factors. Data were analysed for associations using multivariable logistic regression.
Antibody titres for RRV were demonstrated in samples from 134 properties (91%; 95% confidence interval (CI) 87-96%); 22 properties (15%) had BFV reactors (95% CI 12-18%) and 2 properties (1.4%) had WHAV reactors (95% CI -0.5-3.2%). The highest seroprevalence of RRV was in the Townsville-Burdekin region (93%; 95% CI 90-96%) followed by the Mackay-Whitsunday (90%; 95% CI 88-98%) and Far North Coast-Tableland (82%; 95% CI 74-90%) regions. No association (P ≤ 0.05) could be shown between any of the viruses and age groups, sexes, annual average temperature, degree of rainfall or proximity to wet environments. An association with reported large numbers of mosquitoes was seen for RRV but not BFV. A significant association between properties in close proximity to poultry and pigs was shown for BFV.
RRV is endemic within the horse population of northern Queensland, but horses exhibit few clinical signs and could play a role as amplifying hosts in the tropics. Exposure of horses to BFV is significant in northern Queensland and it should be considered a differential diagnosis for RRV. WHAV warrants further study.
调查昆士兰北部马匹中α病毒（罗斯河病毒（RRV）、巴马森林病毒（BFV）和瓦塔罗阿病毒（WHAV））的血清流行率及相关危险因素。
于2013年9月至2014年6月对昆士兰北部147个养殖场的287匹马进行了α病毒抗体的横断面研究。对采样马匹的主人就潜在危险因素进行了访谈。使用多变量逻辑回归分析数据以确定关联。
在来自134个养殖场的样本中检测到RRV抗体滴度（91%；95%置信区间（CI）87 - 96%）；22个养殖场（15%）有BFV反应动物（95% CI 12 - 18%），2个养殖场（1.4%）有WHAV反应动物（95% CI - 0.5 - 3.2%）。RRV血清流行率最高的是汤斯维尔 - 伯德金地区（93%；95% CI 90 - 96%），其次是麦凯 - 圣灵群岛地区（90%；95% CI 88 - 98%）和远北海岸 - 高原地区（82%；95% CI 74 - 90%）。在任何一种病毒与年龄组、性别、年平均温度、降雨量或靠近潮湿环境之间均未显示出关联（P≤0.05）。RRV与报告的大量蚊子存在关联，但BFV不存在。BFV显示出与靠近家禽和猪的养殖场之间存在显著关联。
RRV在昆士兰北部的马群中呈地方性流行，但马匹表现出很少的临床症状，可能在热带地区作为扩增宿主发挥作用。在昆士兰北部，马匹接触BFV的情况较为显著，应将其视为RRV的鉴别诊断疾病。WHAV值得进一步研究。
