FIRST ISOLATION, MOLECULAR DETECTION AND PHYLOGENETIC ANALYSIS OF FMDV A/AFRICA/G1 IN THE SULTANATE OF OMAN

International audience

English. IntroductionFoot and Mouth Disease (FMD) is a transboundary and contagious viral animal disease. It is endemic in several parts of the world. FMD is considered the most economically important and significant endemic viral disease of livestock. Given the genetic diversity of FMD virus (FMDV) and the lack of cross-protection among various viral strains, identification and characterisation of circulating FMDV strain is crucial for effective disease control. So far, the strains of FMDV responsible for outbreaks in Sultanate of Oman remain unknown. In this study, we report for the first time the isolation and molecular characterization of FMDV serotype A topotype G-I circulating in the country between 2018 and 2021. Materials and MethodsFollowing FMD outbreaks and notifications by veterinary authority, a total of 11 oral epithelial tissue samples were collected from cattle from Dhofar, Ad Dhakhyilia, Ash Sharqiyah North and Al Batinah North governorates. The viral RNA was extracted from the samples and screened by real-time retro-transcription polymerase chain reaction (rtRT-PCR). FMDV was isolated on IBRS-2 cells and the serotype of the virus isolates was identified by using an antigen capture ELISA. Molecular characterization of the virus isolates was conducted by conventional RT-PCR amplification of VP1 coding region, sequencing and phylogenetic analyses.ResultsThe FMDV RNA was detected from the 11 samples and isolated after first or second passages on cells. All isolates were found positive for the serotype A by antigen ELISA. Phylogenetic analysis of VP1 sequence revealed one group of A isolates of Africa topotype and G-I genotype. The isolates were genetically similar to the virus TAN/16/2013 (Accession number: MF592653.1) by 92.06% to 95.02% by comparing the available sequences in the gene bank database. DiscussionThis study provides information about the epidemiological situation of FMDV serotype A in Oman and the implication of transboundary transmission of FMD from East Africa. Improved monitoring and surveillance are essential for implementing effective control measures.