Polymerase chain reaction for rapid diagnosis of a recent lumpy skin disease virus incursion to Egypt

In early 2006, a lumpy skin disease (LSD) outbreak has invaded cattle in different localities of Egypt, exerting severe economic losses to livestock industry. Representative specimens (skin biopsies) were collected form nodular skin lesions of infected foreign (imported from Ethiopia, at Ismailia private quarantine) and local cattle (at Fayoum, Menofia and Sharquia governorates). A polymerase chain reaction (PCR) assay was used, as a basic step, for rapid diagnosis of the causative agent in clinical specimens to control spread of infection in the rest of Egypt. The PCR assay, utilizing a LSDV P32 based primer set, could identify LSDV in all outbreak clinical specimens. The specific PCR amplification products (amplicons) were purified and subjected to direct nucleotide sequencing. Blast search, multiple alignments and phylogenetic analyses of the nucleotide sequence data revealed that outbreak LSDV is closely related to other capripoxviruses of LSD, sheep pox and goat pox. Selection and processing of clinical specimens, methods of DNA isolation, and PCR assay applied in this endeavor, presented a reliable laboratory diagnostic tool