Clinico-molecular diagnosis and characterization of bovine lumpy skin disease virus in Andhra Pradesh, India.

Lumpy skin disease (LSD) is an emerging transboundary disease in India. In the recent past, Andhra Pradesh is experiencing outbreaks of LSD in several pockets with a severe economic impact on the farming community. The affected animals showed nodular lesions all over the body in severely affected cases, whereas the lesions were confined to the face, neck, jowl, back, udder, and scrotum in less affected cases. Young ones are highly susceptible to the disease than adults. The mortality was found to be more in young ones than adult cattle which might be due to subsequent secondary bacterial complications. Clinical samples like blood, serum, and tissues were collected randomly from affected animals from four different pockets of Andhra Pradesh. The tissue samples gave positive amplification in PCR targeting LSDV fusion protein gene (ORF 117) and yielded 472 bp product. Another gene specifically targeting ORF036 of LSDV also gave amplification in tissue samples with a product size of 606 bp. The representative samples from four different regions were sequenced for ORF 117 and 036 genes. The phylogeny of the sequenced products of ORF 117 showed more similarity with Kenya Neethling 2490 strain and Russian isolates of 2019. In addition, the phylogeny of ORF 036 showed the path of entry of the virus into the country and also to Andhra Pradesh. The isolates showed similarity with the isolates of India (Odisha), Bangladesh, Russia, Egypt, and Kenya. These studies paved way for the future perspective of developing a vaccine to control the disease.