Cytokine responses in pigs after natural infection with classical swine fever virus.

Classical swine fever (CSF) is a highly contagious viral infection that affects domestic and wild pig population. The classical swine fever virus (CSFV) targets immune cells which perturb the immune functions causing immunopathological disorders such as immunosuppression, leukopenia and haemorrhage. In the present study, ELISA and quantitative real-time reverse transcription PCR (qRT-PCR) analysis was employed to determine cytokine profiles in pigs naturally infected with CSFV using whole blood assay (WBA) under field conditions. Significantly higher TNF-α, IL-10, and IL-6 expression levels were found in unvaccinated pigs infected with CSFV (group B) compared to vaccinated pigs that recovered after CSF (group A), the difference being statistically significant (p = 0.001). However, the expression of IFN-γ was significantly higher in group A compared to group B (p = 0.001). The findings of this field-supported study will help us to understand the immune biology of CSFV infection in infected pigs. The WBA technique can be used as a reliable, fast and feasible in vitro method to assess porcine cellular immune responses as it imitates the porcine blood conditions. Such studies could be of some value in determining the immune status of the ailing animals infected with CSFV. Keywords: classical swine fever virus; immune response; field conditions; interleukin; IFN-γ; TNF-α.

Classical Swine Fever in Wild Hog: Report of its Prevalence in Northeast India.

Classical swine fever virus (CSFV) is the causative agent of a highly contagious disease, hog cholera in pigs. The disease is endemic in many parts of the world and vaccination is the only way to protect the animals from CSFV infection. Wild hogs belong to the species Sus Scrofa Cristatus under the family Suidae are quite susceptible to CSFV infection. The epidemiological role concerning classical swine fever (CSF) in India is largely unknown. We report here the three isolated cases of CSF in wild hogs from three National parks, namely Kaziranga National Park, Manas National Park and Jaldapara National Park, from north-east part of India. The post-mortem and histopathological findings were clearly indicative for CSFV infection. The presence of CSFV genome was demonstrated in several organs and tissues collected from hogs died due to viral infection. In addition, CSF-specific antibodies were detected in two wild hogs as well as in eighteen feral pigs from the same locations. The phylogenetic analysis of the partial E2 protein gene and 5' untranslated region of CSFV isolates from the wild hog showed identities with genotype 2.2 of the Indian isolates. Occurrence of CSF in wild hogs may pose a potent threat in the epidemiology of the virus in Northeast part of India. To the best of our knowledge, the report presented in the manuscript is the first comprehensive report on CSF in wild hogs form Northeast India. The findings reported would help us to understand the epidemiology and biology of CSFV in wild animals.