Asia Pacific Centre for Animal Health, Melbourne Veterinary School, Faculty of Science, The University of Melbourne, Victoria, Australia.
Research Institute for the Environment and Livelihoods, Charles Darwin University, Darwin, Northern Territory, 0909, Australia.
Aust Vet J. 2024 Nov;102(11):550-563. doi: 10.1111/avj.13369. Epub 2024 Sep 30.
Feline calicivirus (FCV) commonly causes upper respiratory tract, oral and ocular infections in species of the family Felidae, with high prevalence amongst domestic cat (Felis catus) populations worldwide. Detection of FCV-specific antibodies in serum provides evidence of previous infection with FCV and an indication of whether a cat may be protected against clinical FCV disease. This study describes the most extensive sampling for anti-FCV antibodies in feral and stray cat populations in Australia, and examines variation in prevalence associated with cat age, sex and location.
Blood samples were opportunistically collected from 669 feral, stray or Indigenous community cats from the Northern Territory, South Australia, Victoria, south-east Tasmania and south-west New South Wales. The sera were harvested and tested for antibodies capable of neutralising the FCV vaccine strain F9 by serum-virus neutralisation assay.
Of the 669 cats tested, 69.7% had detectable FCV-F9-neutralising antibodies (titres ≥5). Maturity was significantly associated with higher seroprevalence and higher antibody titres, with adult cats being more than twice as likely to have detectable FCV-neutralising antibodies than subadults. Male cats had a higher seroprevalence and slightly higher antibody titres than females. Cats living in closer proximity to humans had significantly higher seroprevalences and higher FCV-neutralising antibody titres than feral cats from more remote regions of Australia.
Australian feral and stray cats have a high risk of natural exposure to and infection with FCV, with the prevalence and levels of pre-existing immunity to FCV being highest amongst adult cats living in highly modified urban, peri-urban and agricultural environments.
猫杯状病毒（FCV）通常会引起猫科动物的上呼吸道、口腔和眼部感染，在全球范围内，家猫（Felis catus）种群中FCV 的流行率很高。血清中 FCV 特异性抗体的检测提供了 FCV 既往感染的证据，并表明猫是否可能免受临床 FCV 疾病的侵害。本研究描述了在澳大利亚对野生和流浪猫群体中针对 FCV 的抗体进行的最广泛采样，并检查了与猫年龄、性别和位置相关的流行率变化。
从北领地、南澳大利亚、维多利亚、塔斯马尼亚东南部和新南威尔士西南部的 669 只野生、流浪或土著社区猫中机会性采集血液样本。收获血清并通过血清病毒中和试验检测能够中和 FCV 疫苗株 F9 的抗体。
在 669 只测试的猫中，69.7%的猫具有可检测到的 FCV-F9 中和抗体（滴度≥5）。成熟度与更高的血清阳性率和更高的抗体滴度显著相关，成年猫比亚成年猫更有可能检测到 FCV 中和抗体，几率是其两倍多。雄性猫的血清阳性率和抗体滴度略高于雌性猫。与生活在澳大利亚偏远地区的野生猫相比，与人类更接近的猫具有更高的血清阳性率和更高的 FCV 中和抗体滴度。
澳大利亚的野生和流浪猫有很高的自然感染 FCV 的风险，在生活在高度人为改变的城市、城郊和农业环境中的成年猫中，FCV 的流行率和预先存在的免疫水平最高。
