Molecular characterization and phylogenetic analysis of lumpy skin disease in Egypt.

Lumpy skin disease (LSD) is an infectious viral disease affecting cattle, cause severe economic losses. In the last few years, the disease is widely distributed in many countries in the Middle East, including Egypt. This study aimed to determine the genetic character of LSDV circulating in some governorates in Egypt and its relation with other LSDVs and vaccine strains in GenBank. A total of 50 skin nodules and 50 blood samples were collected from clinically affected cattle to detect LSDV using PCR targeting the P32 gene. The positive samples were characterized using PCR targeting the GPCR gene. The amplified products of four samples detected in the skin nodule of cattle from Alexandria and Kafr ElSheikh governorates were sequenced, and the phylogenetic tree was constructed. Out of 100 analyzed samples, 70 samples were positive for LSDV by PCR assay. In addition, the sequence alignment of the obtained LSDV strains detected in the Alexandria governorate showed high similarity to the LSDV genome (MN995838). In contrast, LSDV strains from Kafr ElSheikh governorate revealed high similarity and the previous Egyptian strain (MG970343), which was isolated from cattle in Sharkia governorate in 2016. Also, the phylogenetic analysis confirmed that one of the LSDV strain (LC601598) from Alexandria is closely related to the LSDV of Menofia/Egypt/2019 (MN271722), while another one (LC601597) is closely related to vaccine strains of LSDV. Moreover, the LSDV strains from Kafr Elsheikh showed closely related to previous LSDV strains isolated from Menofia (MG970343) and Dakahlia (KP071936) governorates and clustered with other LSDV strains in a distinct cluster. This information is for understanding the epidemiology of LSDV and supporting the establishment of an efficient control program for the disease.