Fiegna C, Dagleish M P, Coulter L, Milne E, Meredith A, Finlayson J, Di Nardo A, McInnes C J
Moredun Research Institute, Pentlands Science Park, Penicuik, Edinburgh EH26 0PZ, Scotland, UK.
The Royal (Dick) School of Veterinary Studies and The Roslin Institute, University of Edinburgh, Easter Bush Campus, Roslin, Midlothian EH25 9RG, Scotland, UK.
Vet Microbiol. 2016;182:18-27. doi: 10.1016/j.vetmic.2015.10.012. Epub 2015 Nov 10.
To improve our understanding of squirrelpox virus (SQPV) infection in the susceptible host, three red squirrels were challenged with wild-type SQPV via scarification of the hind-limb skin. All squirrels seroconverted to the infection by the end of the experiment (17 days post-challenge). Challenged animals suffered disease characterised by the development of multiple skin and oral lesions with rapid progression of skin lesions at the infection site by day 10 post-challenge. No internal pathological changes were found at post-mortem examination. A novel SQPV Taqman(®) Real-time PCR detected viral DNA from multiple organs, with the largest amounts consistently associated with the primary and secondary skin and oral lesions where viral replication was most likely occurring. Immunohistochemistry clearly detected viral antigen in the stratified squamous epithelium of the epidermis, tongue and the oropharyngeal mucosa-associated lymphoid tissue and was consistently associated with histological changes resulting from viral replication. The lack of internal pathological changes and the detection of relatively low levels of viral DNA when compared with primary and secondary skin lesions argue against systemic disease, although systemic spread of the virus cannot be ruled out. This study allowed a comprehensive investigation of the clinical manifestation and progression of SQPV infection with a quantitative and qualitative analysis of virus dissemination and shedding. These findings suggest two separate routes of SQPV transmission under natural conditions, with both skin and saliva playing key roles in infected red squirrels.
为了增进我们对松鼠痘病毒（SQPV）在易感宿主中感染情况的了解，通过划破后肢皮肤的方式，用野生型SQPV对三只红松鼠进行了攻毒。在实验结束时（攻毒后17天），所有松鼠都出现了针对该感染的血清转化。攻毒动物出现了疾病症状，其特征为出现多处皮肤和口腔损伤，在攻毒后第10天，感染部位的皮肤损伤迅速发展。尸检未发现内部病理变化。一种新型的SQPV Taqman（®）实时荧光定量PCR检测到多个器官中有病毒DNA，其中含量最高的始终与原发性和继发性皮肤及口腔损伤相关，而这些部位最有可能发生病毒复制。免疫组织化学在表皮、舌头和口咽黏膜相关淋巴组织的复层鳞状上皮中清晰地检测到病毒抗原，并且始终与病毒复制引起的组织学变化相关。与原发性和继发性皮肤损伤相比，缺乏内部病理变化以及检测到相对较低水平的病毒DNA，这表明不存在全身性疾病，尽管不能排除病毒的全身扩散。本研究通过对病毒传播和排出进行定量和定性分析，对SQPV感染的临床表现和病程进行了全面调查。这些发现表明，在自然条件下，SQPV有两种不同的传播途径，皮肤和唾液在受感染的红松鼠中都起着关键作用。
