Isolation, Antigenic and Molecular Characterization of Sheeppox Virus from Clinical Cases in Egypt

Sheep pox is a viral diseases of sheep characterized by fever, generalized papules or nodules, vesicles (rarely), lesions in internal organs and death. Sheeppox virus (SPPV) is the causative agents of Sheeppox, together with goat pox virus (GPV) and lumpy skin disease virus (LSDV) make up the genus Capri poxvirus in the family Poxviridae. The aim of the current study is to monitor and follow up the current situation of Sheeppox (SPPV) in Egypt. A total of thirty-two samples (scabs, biopsies from skin nodules and necropsies from internal organs) were collected from suspected infected sheep with SPPV from two Egyptian governorates (Beheira and Giza) during the summer season of 2018 and 2019. Virus isolation into embryonated chicken eggs (ECEs), transmission electron microscope (TEM), and molecular identification were carried out. Our results revealed that nineteen samples (19/32; 56.4%) were positive based on virus isolation into ECEs. Two representative positive samples were examined using TEM that showed protein filaments projected from the external membrane. Meanwhile, fifteen samples out of nineteen positive samples from virus isolation (15/19; 78.9%) were positive based on polymerase chain reaction (PCR) followed by sequencing and phylogenetic analysis for representative two samples, which revealed high percentage of identity with SPPV reference stains from different countries including Egypt. In conclusions, our findings revealed that the circulation of SPPV within the Egyptian field. Further studies and surveillance are required to monitor the virus evolution and transmission pathways to better understand the virus pathobiology that will help for SPPV control.