African swine fever (ASF) is one of the most important transboundary diseases of pigs. ASF has been identified in India for the first time in domestic pigs from outbreaks reported in two of the northeastern states, Arunachal Pradesh and Assam in 2020. A total of 11 ASF outbreaks in different regions killed over 3700 pigs and devastated the economy of small-scale livestock owners of both the states. Considering the first outbreak of ASF in India, a generic risk assessment framework was determined to identify potential risk factors that might favor future emergence of the disease. Based on the Indian scenario, we considered population density of host, farming practice, availability of biological vectors and wildlife reservoirs, epidemiological cycles, and international trade to analyze the possibility of future outbreaks of ASF and chances of establishment of endemism. On critical analysis of the identified risk factors associated with ASFV transmission, we observed that the risk factors are well preserved in the Indian geography and might participate in future outbreaks, further disseminating the disease to nearby countries. Since no vaccine is currently available against ASF, the domestic and the wild pigs (wild boars and the endangered pygmy hogs native to India) of this region are under constant threat of infection. For the near future, this region will have to continue to rely on the implementation of preventive measures to avoid the devastating losses that outbreaks can cause. The various adaptive control strategies to minimize the risks associated with the transmission of ASF, keeping our views to Indian settings, have been described. The risk-analysis framework presented in the study will give a further understanding of the dynamics of disease transmission and will help to design control strategies and corresponding measures to minimize the catastrophic consequences of ASF disease.

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Outbreaks of swinepox [caused by a swinepox virus (SWPV)] in pigs were investigated in 3 districts of Assam, a north eastern state of India. Diagnosis of the disease was carried out employing both standard virological as well as molecular methods. Three representative isolates from different places were selected for inoculation into confluent monolayers of Porcine Kidney-15 (PK-15) cell line. The cytopathic effects were characterized by cell rounding, nuclear vacuolation, cell fusion, granulation of cells and finally detachment from third blind passage onwards. The three genes viz., SPV18-20 and P42 of SWPV was targeted for confirmation of the virus. Swinepox virus was successfully adapted to the PK-15 cell line from seventh passage onwards. The isolated viruses were characterized by sequencing and phylogenetic analysis of P42 gene (extracellular envelope protein), a homologue of vaccinia virus F13L gene. In India, studies on swine pox are very limited. This is the first report on successful isolation of swinepox virus from north eastern region of India. Assam and the other north-eastern states of India being a hub for pig husbandry, isolation of swinepox virus will help in developing and formulating control strategies against the disease.

Africa Swine Fever (ASF) is one of the most important transboundary diseases of pigs. ASF has been identified in India for the first time in domestic pigs from outbreaks reported in two of the North-Eastern states, Arunachal Pradesh and Assam in 2020. A total of 11 ASF outbreaks in different regions killed over 3700 pigs and devastated the economy of small-scale livestock owners of both the states. Considering the first outbreak of ASF in India, a generic risk assessment framework was determined to identify potential risk factors that might favour future emergence of the disease. Based on Indian scenario, we considered population density of host, farming practice, availability of biological vectors and wildlife reservoirs, epidemiological cycles and international trade to analyze the possibility of future outbreaks and chances of establishment of endemism. On critical analysis of the identified risk factors, we observed that the risk factors are well preserved in Indian geography and might participate in future outbreaks further disseminating the disease to nearby countries. Since no vaccine is currently available against ASF, the domestic and the wild-pigs (wild boars and the endangered pygmy hogs native to India) of this region are under constant threat of infection. For the near future this region will have to continue to rely on the implementation of preventive measures to avoid the devastating losses that outbreaks can cause. The various adaptive control strategies to minimize the risks associated with the transmission of ASF keeping our views to Indian settings have been described. The risk-analysis framework presented in the study will give a further understanding of the dynamics of disease transmission and will help to design control strategies and corresponding measures to minimize the catastrophic consequences of ASF disease.

Two outbreaks of Swinepox in pig population of north-east India were investigated. The disease was diagnosed based on clinical signs, lesions, electron microscopy and by molecular techniques. The virus was identified by PCR amplification targeting the viral late transcription factor-3 (VLTF-3) gene of swinepox virus. The VLTF-3 gene was cloned and sequenced. Phylogenetic analysis based on VLTF-3 gene sequence showed that the Swinepox viruses identified in these outbreaks were clustered along with the other Swinepox isolates reported across the globe and were distinctly separated from the other members of the poxviridae family. The north-eastern states of India, being a hub for pig husbandry, are the home for over a quarter of all India's pig population. Till now swinepox was not reported from this part of India. To the authors' knowledge, this is the first report on detection and characterization of swinepox from the north-eastern part of India.