A wild porcine hemagglutinating encephalomyelitis virus strain (PHEV-CC14) was isolated from an acute outbreak in piglets, causing nonsuppurative encephalitis and sharing 95%-99.2% nucleotide identity with other PHEV strains.
The study identifies PHEV-induced nonsuppurative encephalitis as the cause of death in piglets, providing a reference for experimental diagnosis and vaccine development.
An acute outbreak of porcine hemagglutinating encephalomyelitis virus (PHEV) infection in piglets, characterized with neurological symptoms, vomiting, diarrhea, and wasting, occurred in China. Coronavirus-like particles were observed in the homogenized tissue suspensions of the brain of dead piglets by electron microscopy, and a wild PHEV strain was isolated, characterized, and designated as PHEV-CC14. Histopathologic examinations of the dead piglets showed characteristics of non-suppurative encephalitis, and some neurons in the cerebral cortex were degenerated and necrotic, and neuronophagia. Similarly, mice inoculated with PHEV-CC14 were found to have central nervous system (CNS) dysfunction, with symptoms of depression, arched waists, standing and vellicating front claws. Furthmore, PHEV-positive labeling of neurons in cortices of dead piglets and infected mice supported the viral infections of the nervous system. Then, the major structural genes of PHEV-CC14 were sequenced and phylogenetically analyzed, and the strain shared 95%-99.2% nt identity with the other PHEV strains available in GenBank. Phylogenetic analysis clearly proved that the wild strain clustered into a subclass with a HEV-JT06 strain. These findings suggested that the virus had a strong tropism for CNS, in this way, inducing nonsuppurative encephalitis as the cause of death in piglets. Simultaneously, the predicted risk of widespread transmission showed a certain variation among the PHEV strains currently circulating around the world. Above all, the information presented in this study can not only provide good reference for the experimental diagnosis of PHEV infection for pig breeding, but also promote its new effective vaccine development.
Li et al. (Thu,) conducted a other in Porcine hemagglutinating encephalomyelitis virus (PHEV) infection (n=140). Porcine hemagglutinating encephalomyelitis virus (PHEV) infection was evaluated on Detection and isolation of PHEV from brain tissue. A wild porcine hemagglutinating encephalomyelitis virus strain (PHEV-CC14) was isolated from an acute outbreak in piglets, causing nonsuppurative encephalitis and sharing 95%-99.2% nucleotide identity with other PHEV strains.