evaluation of the antiviral effects of methanolic extract of olive leaves on border disease virus in cell culture conditions

Border disease virus (bdv) is an important pathogen reported globally. bdv belongs to the genus pestivirus and the family flaviviridae and can cause significant economic losses due to congenital disorders, abortions, stillbirths, birth of weak lambs with tremors, immunosuppression and increased risk of other infections. its diagnosis is challenging due to interspecies transmission between sheep, cattle and pigs. olive leaves are a medicinal plant containing phenolic and oleuropein compounds known as a cost-effective and accessible source of polyphenols. they have been widely used in ancient medicine. the main source of bdv infection is persistently infected animals. there is currently no vaccine available in the uk, but there are vaccines available in the us and other areas of europe. while there are vaccines, not all authorities consider them efficacious. this study aims to investigate the effect of methanolic extracts of olive leaves on bdv titer. in this experimental study, olea europaea was used to assess its antiviral effects against bdv. methanolic extracts of this plant were prepared at concentrations of 50, 100, 200 and 400 mg /ml, and were tested against bdv. the objective was to determine the viral titer using tcid50 in the mdbk cell line. the most significant effect of methanolic extracts of olive leaves on bdv was observed at concentrations of 400 mg /ml. there was a significant difference in reductions of viral titer using the tcid50 method. methanolic extracts of olive leaves reduced the infectious titer of bdv.