EPIUnit - Instituto de Saúde Pública, Universidade do Porto, Porto, Portugal; Laboratório para a Investigação Integrativa e Translacional em Saúde Populacional (ITR), Porto, Portugal; 1H -TOXRUN - One Health Toxicology Research Unit, University Institute of Health Sciences, CESPU, CRL, 4585-116 Gandra, Paredes, Portugal (PB, NVB).
CECAV-Animal and Veterinary Research Centre, Trás-os-Montes e Alto Douro University, Quinta de Prados, Vila Real, Portugal (ACA).
Acta Trop. 2024 Jun;254:107202. doi: 10.1016/j.actatropica.2024.107202. Epub 2024 Mar 31.
Cervids are highly exposed to ticks, however, their role in the life cycle of these rickettsiae has not been fully elucidated. Given the expanding distribution and growing population of deer species in Portugal, coupled with their direct and indirect interactions with humans during hunting, it becomes crucial to explore their role as sentinels and potential reservoirs of Rickettsia. The present investigation aimed to detect and evaluate exposure to Rickettsia in free-living deer from Portugal. Blood samples (n = 77) were collected from hunted game animals (red deer and fallow deer) from different areas throughout Portugal (Idanha-a-Nova, Monte Fidalgo, Montalvão and Arraiolos) and sera were tested by immunofluorescence assay, to detect antibodies. Additionally, blood DNA samples were screened for SFGR by nested-polymerase chain reaction targeting a fragment of the outer membrane protein B (ompB) gene, as well as for Anaplasma and Ehrlichia spp. targeting the 16S rRNA gene. Thirty-five per cent (25 deer and two fallow deer) tested positive (sera with a titer ≥1:64) for IgG antibodies against Rickettsia conorii. No rickettsial DNA was detected by PCR for the ompB gene, and all DNA samples tested negative for Anaplasma and Ehrlichia. As far as we know, this study is the first screening of cervid species in Portugal for Rickettsia antibodies. The findings suggest that these animals serve as useful sentinel indicators for the circulation of rickettsiae, offering a complementary perspective to studies focused on ticks. The increasing numbers of hunted deer in Portugal and the potential zoonotic features of Rickettsia spp. highlight the importance of continued surveillance directed at tick-borne diseases, especially those involving wild animals.
鹿科动物高度暴露于蜱虫之下，但它们在这些立克次体的生命周期中的作用尚未完全阐明。鉴于葡萄牙鹿种的分布范围不断扩大，种群数量不断增加，再加上它们在狩猎期间与人类的直接和间接互动，探索它们作为立克次体的哨点和潜在宿主的作用变得至关重要。本研究旨在检测和评估葡萄牙自由生活的鹿对立克次体的暴露情况。从葡萄牙不同地区（伊达尼亚-诺瓦、蒙泰菲达尔戈、蒙塔尔万和阿罗约洛斯）的狩猎野生动物（马鹿和黇鹿）中采集血液样本（n=77），并通过免疫荧光测定法检测血清，以检测抗体。此外，还通过针对外膜蛋白 B（ompB）基因片段的巢式聚合酶链反应筛选血液 DNA 样本，以检测 SFGR，以及针对 16S rRNA 基因的 Anaplasma 和 Ehrlichia spp。针对 Rickettsia conorii 的 IgG 抗体，35%（25 只鹿和两只黇鹿）的血清呈阳性（滴度≥1:64）。ompB 基因的 PCR 未检测到立克次体 DNA，所有 DNA 样本均为 Anaplasma 和 Ehrlichia 阴性。据我们所知，这是葡萄牙首次对鹿科动物进行立克次体抗体筛查。研究结果表明，这些动物作为循环立克次体的有用哨点指示物，为专注于蜱虫的研究提供了补充视角。葡萄牙被狩猎的鹿数量不断增加，以及立克次体 spp. 的潜在人畜共患病特征，突显了继续针对蜱传疾病进行监测的重要性，尤其是那些涉及野生动物的疾病。
