Istituto Zooprofilattico Sperimentale del Lazio e della Toscana "M. Aleandri", Rome, Italy.
Regional Service for Surveillance and Control of Infectious Diseases (SERESMI), National Institute for Infectious Diseases "Lazzaro Spallanzani" IRCCS, Rome, Italy.
Epidemiol Infect. 2020 Jan 20;148:e9. doi: 10.1017/S0950268819002115.
A cross-sectional survey was carried out to estimate the seroprevalence of Coxiella burnetii in extensively grazed cattle and sheep from central Italy and to identify the related risk factors. Data on notified human Q fever cases in the area were also collected and described. A two-stage cluster sampling was performed. A total of 5083 animals (2210 cattle; 2873 sheep) belonging to 186 farms (92 herds; 94 flocks) were tested for the presence of antibodies against C. burnetii using a commercial enzyme-linked immunosorbent assay kit. The prevalence at the animal-level resulted three times higher in sheep compared to cattle (37.8% vs. 12.0%; χ2 = 270.10, P < 0.001). The prevalence at the herd-level was also higher in sheep than in cattle (87.2% vs. 68.5%; χ2 = 9.52, P < 0.01). The multivariate analysis showed a higher risk of seropositivity for cattle aged 67-107 months (OR 2.79, 95% CI 1.86-4.18), cattle >107 months of age (OR 2.07, 95% CI 1.36-3.14) and mixed breed cattle (OR 1.74, 95% CI 1.11-2.72). A herd size >92 animals was recognized as herd-level risk factor in cattle (OR 6.88, 95% CI 1.67-28.37). The risk of being seropositive was double in sheep belonging to flocks >600 animals (odds ratio (OR) 2.04, 95% CI 1.63-2.56). Sheep were confirmed to be the most exposed species. Nevertheless, the prevalence observed in cattle also suggests the potential involvement of this species in the circulation of the pathogen in the area. Seven confirmed human Q fever cases were reported. In five out of seven cases there was at least one exposed herd within a 5 km buffer. Even though the source of the infection was not identified, the possibility of C. burnetii circulating in the livestock and human population in the study area cannot be overlooked. The integration between veterinary and human surveillance will be crucial to understand the spread of this zoonosis and to support the adoption of appropriate control measures.
本研究开展了一项横断面调查，以评估意大利中部广泛放牧的牛和羊中贝氏柯克斯体的血清流行率，并确定相关的风险因素。同时还收集和描述了该地区报告的人类 Q 热病例数据。采用两阶段聚类抽样方法，对来自 186 个农场（92 个畜群；94 个羊群）的 5083 只动物（2210 头牛；2873 只羊）进行了检测，以确定其是否存在针对 C. burnetii 的抗体。结果显示，绵羊的血清流行率是牛的三倍（37.8%比 12.0%；χ2=270.10，P<0.001）。畜群水平的流行率在绵羊中也高于牛（87.2%比 68.5%；χ2=9.52，P<0.01）。多因素分析显示，67-107 月龄（OR 2.79，95%CI 1.86-4.18）、107 月龄以上（OR 2.07，95%CI 1.36-3.14）和混合品种牛（OR 1.74，95%CI 1.11-2.72）患阳性的风险更高。畜群规模>92 只动物被认为是牛的畜群水平风险因素（OR 6.88，95%CI 1.67-28.37）。畜群规模>600 只的绵羊感染阳性的风险是畜群规模<600 只绵羊的两倍（比值比（OR）2.04，95%CI 1.63-2.56）。绵羊被确认为最易感染的物种。然而，牛中观察到的流行率也表明，该物种可能参与了该地区病原体的传播。报告了 7 例确诊的人类 Q 热病例。在 7 例病例中，有 5 例在 5 公里缓冲区范围内至少有一个暴露的畜群。尽管未确定感染源，但不能忽视该病原体在研究地区牲畜和人群中传播的可能性。兽医和人类监测的结合将是了解这种人畜共患病传播并支持采取适当控制措施的关键。
