家犬(犬类)与人类生活在一起,经常接触其他动物,并可能作为病毒传播的中间宿主。自由漫游的狗,占世界家犬数量的70%以上,在这方面可能构成特别高的风险。我们在乌干达的三个地方进行了狗病毒的流行病学研究,代表低,与野生动物接触的中等和高比率,从专门为生物多样性和疾病“热点”中的传统狩猎而拥有的狗到富裕郊区的宠物。我们通过主人访谈量化了狗和野生动物之间的接触率,并进行了犬兽医健康评估。然后我们将广谱病毒宏基因组学应用于血浆样本,我们从中鉴定出46种病毒,其中44个以前没有描述过,在三个病毒家族中,虫卵病毒科,细小病毒科和钩耳病毒科。所有46种病毒(100%)发生在狗的高接触人群中,而在中接触和低接触人群中分别为63%和39%。分别。病毒流行率在病毒中介于2.1%至92.0%之间,并且是最高的,平均而言,在高接触人群(22.3%)中,其次是中等接触人群(12.3%)和低接触人群(4.8%)。病毒丰富度(每只狗的病毒数量)范围从0到27,并且明显更高,平均而言,高接触人群(10.2)比中等接触人群(5.7)或低接触人群(2.3)。病毒丰富度与狗每年喂食野生动物的次数呈强烈正相关,与身体状况评分呈负相关,体温和细胞体积。病毒丰度(累积归一化宏基因组读数密度)在狗中变化124倍,平均而言,狗的高接触人群比低接触或中等接触人群高4.1倍和2.4倍,分别。病毒丰度也与狗每年被喂食野生动物的次数密切相关,与压积细胞体积呈负相关,与白细胞计数呈正相关。这些趋势是由钩虫科中的9种病毒驱动的,沙氏病毒属,Sedoreoviridae家族中的一种新型病毒,Orbivirus属。Orbivirus属含有人畜共患病毒和狗可以通过摄入受感染的肉而获得的病毒。总的来说,我们的研究结果表明,病毒的流行,丰富度和丰度在狗和野生动物之间的接触梯度中增加,并且狗的健康状况改变了病毒感染。其他生态,地理和社会因素也可能促成了这些趋势。我们在与野生动物接触程度较高的狗中发现了一种新型的Orbivirus,这支持了这样一种观点,即自由漫游的狗可以作为对人类和其他动物具有医学重要性的病毒的中介宿主。
Domestic dogs (Canis lupus familiaris) live with humans, frequently contact other animals and may serve as intermediary hosts for the transmission of viruses. Free-roaming dogs, which account for over 70% of the world\'s domestic dog population, may pose a particularly high risk in this regard. We conducted an epidemiological study of dog viromes in three locations in Uganda, representing low, medium and high rates of contact with wildlife, ranging from dogs owned specifically for traditional hunting in a biodiversity and disease \'hotspot\' to pets in an affluent suburb. We quantified rates of contact between dogs and wildlife through owner interviews and conducted canine veterinary health assessments. We then applied broad-spectrum viral metagenomics to blood plasma samples, from which we identified 46 viruses, 44 of which were previously undescribed, in three viral families, Sedoreoviridae, Parvoviridae and
Anelloviridae. All 46 viruses (100 %) occurred in the high-contact population of dogs compared to 63 % and 39 % in the medium- and low-contact populations, respectively. Viral prevalence ranged from 2.1 % to 92.0 % among viruses and was highest, on average, in the high-contact population (22.3 %), followed by the medium-contact (12.3 %) and low-contact (4.8 %) populations. Viral richness (number of viruses per dog) ranged from 0 to 27 and was markedly higher, on average, in the high-contact population (10.2) than in the medium-contact (5.7) or low-contact (2.3) populations. Viral richness was strongly positively correlated with the number of times per year that a dog was fed wildlife and negatively correlated with the body condition score, body temperature and packed cell volume. Viral abundance (cumulative normalized metagenomic read density) varied 124-fold among dogs and was, on average, 4.1-fold higher and 2.4-fold higher in the high-contact population of dogs than in the low-contact or medium-contact populations, respectively. Viral abundance was also strongly positively correlated with the number of times per year that a dog was fed wildlife, negatively correlated with packed cell volume and positively correlated with white blood cell count. These trends were driven by nine viruses in the family
Anelloviridae, genus Thetatorquevirus, and by one novel virus in the family Sedoreoviridae, genus Orbivirus. The genus Orbivirus contains zoonotic viruses and viruses that dogs can acquire through ingestion of infected meat. Overall, our findings show that viral prevalence, richness and abundance increased across a gradient of contact between dogs and wildlife and that the health status of the dog modified viral infection. Other ecological, geographic and social factors may also have contributed to these trends. Our finding of a novel orbivirus in dogs with high wildlife contact supports the idea that free-roaming dogs may serve as intermediary hosts for viruses of medical importance to humans and other animals.