Investigation of ectyma contagiosum infection by virological methods and virus isolation in Turkey

Ecthyma (Orf) is an infectious disease caused by the ORF virus (ORFV), a member of the Parapoxvirus genus. The disease, which affects small ruminants and sometimes other wild animals, can be seen wherever sheep and goats are raised. This study was planned to epidemiologically reveal the presence of ORFV in sheep and goat herds in Turkey, its molecular characterization, and also the effects of the virus on animals both in and outside the outbreak. In this study, 70 materials (10 lesion tissue/31 swabs/18 EDTA blood/11 skin scrapings) from 22 farms in 14 cities (Aydın, Denizli, Elazığ, Iğdır, İzmir, Kars, Manisa, Muğla, Nevşehir, Samsun, Sinop, Sivas, Rize and Tokat) were tested with Real-Time PCR. 45 positive and 25 negative were determined from 70 materials. According to the findings obtained from this study, it was determined that animal species and age groups did not have a significant (p<0.05) effect on the results. It was determined that the sampling methods gave significant (p<0.05) results in the detection of nucleic acid presence in the test performed with Real Time PCR. Samples with ORFV genome presence were inoculated into African green monkey (Cercopithecus aethiops) kidney (Vero) continuous cell cultures for virus isolation. Molecular characterization of samples that were positive for ORFV genome presence and were also isolated in Vero continuous cell cultures and identified with Real Time PCR was performed by service procurement. Madin-Darby Bovine Kidney (MDBK) continuous cell cultures were used in the production of the reference E(P)CK20 ORFV strain used in the project and in the serum neutralization test (SNT). According to the status of animal presence in farms that are closest to the herds with virus-positive animals and also 10 km and/or more away from the focus areas, SNT was performed to detect antibodies in a total of 540 sera taken from sheep and goats at the end of the 10th week following the disease notification. 4 positive and 536 negative were detected with the SNT. In the comparison made between animal species and genders in the study, no significant result (p>0.05) was determined in the detection of antibodies with SNT both in the regions close to the farm where the outbreak occurred and in the remote regions outside the 10 km area. Phylogenetic analysis of B2L, F1L and VIR gene regions of ORFV was performed. When the vaccine strain of ORFV circulating in our country and other isolates entered into the genbank were compared, it was determined that there were changes in terms of both nucleotide and amino acid similarity. When compared with other country sequences, it was seen that it was closely genetically related to various countries, especially China, India, Spain, and Greece. The study concluded that ORFVs circulate widely within the country, animal movements play an important role in this circulation, and that protection and control efforts should be effective and vaccine use should be expanded.