The aim of this study is to investigate the potential role of ixodid (hard) ticks in the transmission of lumpy skin disease (LSD), which is an economically important disease of cattle and is caused by the LSD virus (LSDV). LSD is endemic in most countries of Africa and Middle East and can be transmitted either by mechanical as well as intrastadial and transstadial routes. Since capripoxviruses are serologically identical, their specific identification relies exclusively on the use of molecular tools. In this study, we analysed the G-protein-coupled chemokine receptor (GPCR) genes of two LSDV isolates from Ixodid (hard) ticks (Amblyomma hebraeum) in Egypt. Multiple alignments of the nucleotide sequences revealed that both isolates had nine nucleotide mutations in comparison with the local reference strain, LSDV-Egypt/89 Ismalia.
Compared with the GPCR sequences of SPV and GPV strains, 21 nucleotide insertion and 12 nucleotides deletions were identified in the GPCR genes of our isolates and other LSDVs. The amino acid sequences of GPCR genes of our isolates contained the unique signature of LSDV (A11, T12, T34, S99 and P199). Phylogenetic analyses showed that the GPCR genes of LSDVs identified from ticks were closest genetically to the previously detected LSDVs from infected ruminants, indicating a potential role of Ixodid ticks for transmission of LSDV. This study showed the role of A. hebraeum ticks for transmission of LSDV. So, tick control is a crucial part, which should be included as a part of LSDV control measures in endemic countries.