University of Agricultural Sciences and Veterinary Medicine of Cluj-Napoca, Cluj- Napoca, RO-400372, Romania.
"Iuliu Hațieganu" University of Medicine and Pharmacy, Cluj-Napoca, Romania.
BMC Vet Res. 2023 Sep 29;19(1):177. doi: 10.1186/s12917-023-03729-7.
Toxoplasma gondii is a protozoan parasite that infects a large spectrum of warm-blooded animals, including humans. Small rodents and insectivores play an important role in the epidemiology of T. gondii and may serve as a source of infection for both, domestic and wild definitive felid hosts. Factors influencing the occurrence of T. gondii in wild small mammals are unknown, despite the fact that many intermediate host species are identified. We have used small mammals (Rodentia and Lipotyphla) captured over two years in various habitats, both in urbanised and in natural landscapes. We assessed the importance of land-use, season and host ecology on T. gondii infection.
We examined 471 individuals belonging to 20 small mammal species, collected at 63 locations spread over wide altitude, habitat and land-use ranges from Romania. Heart tissue samples were individually analysed by PCR targeting the 529 bp repetitive DNA fragment of T. gondii. The overall prevalence of infection was 7.3%, with nine species of rodents and two species of shrews being found to carry T. gondii DNA. Five species showed high frequency of infection, with the highest prevalence found in Myodes glareolus (35.5%), followed by Spermophilus citellus (33.3%), Sorex minutus (23.1%), S. araneus (21.7%) and Micromys minutus (11.1%). Adults seemed more often infected than young, however when controlling for season, the difference was not significant, as in spring both adults and young showed higher infection rates, but more adults were sampled. Contrary to our expectations, urban/rural areas (with their implicit high density of domestic feline presence) had no effect on infection prevalence. In addition, neither habitat, nor land-use at sampling sites was important as only geographical location and host species were contributing factors to the infection risk.
High prevalence of T. gondii infection showed a highly localised, patchy occurrence, with long living and higher mobility host species being the most common carriers, especially during autumn.
刚地弓形虫是一种原生动物寄生虫，感染范围广泛，包括人类在内的多种温血动物。小型啮齿动物和食虫动物在刚地弓形虫的流行病学中起着重要作用，它们可能是家养和野生终末宿主的感染源。尽管已经确定了许多中间宿主物种，但影响野生小型哺乳动物中刚地弓形虫发生的因素尚不清楚。我们使用了在不同生境中捕获的两年多的小型哺乳动物（啮齿目和食虫目），包括城市化和自然景观中的物种。我们评估了土地利用、季节和宿主生态对刚地弓形虫感染的重要性。
我们检查了 471 只属于 20 种小型哺乳动物的个体，这些个体来自罗马尼亚 63 个地点，分布范围广泛，包括海拔、生境和土地利用类型。心脏组织样本通过针对刚地弓形虫 529bp 重复 DNA 片段的 PCR 进行个体分析。总的感染率为 7.3%，9 种啮齿动物和 2 种鼩鼱携带刚地弓形虫 DNA。5 种物种显示出高感染频率，其中麦氏田鼠的感染率最高（35.5%），其次是黑线仓鼠（33.3%）、巢鼠（23.1%）、白腹巨鼠（21.7%）和小家鼠（11.1%）。成年个体似乎比幼体更容易感染，但当控制季节因素时，差异并不显著，因为在春季，成年和幼体都显示出更高的感染率，但成年个体的样本更多。与我们的预期相反，城市/农村地区（由于其隐含的家猫高密度存在）对感染率没有影响。此外，栖息地和采样点的土地利用都不重要，因为只有地理位置和宿主物种是感染风险的因素。
高感染率表明刚地弓形虫感染具有高度本地化、斑块状的发生方式，具有长寿命和更高迁移性的宿主物种是最常见的携带者，尤其是在秋季。
