ISOLATION, SEROTPYING, AND MOLECULAR DETECTION OF BOVINE FOOT AND MOUTH DISEASE VIRUS FROM OUTBREAK CASES IN SELECTED AREAS OF KELLEM WOLLEGA, WEST, AND EAST WOLLEGA ZONES, WESTERN ETHIOPIA.

ABSTRACT

Foot-and-Mouth Disease is a highly contagious and economically important trans boundary viral disease affecting domestic and wild cloven-hoofed animals. An outbreak-based study design was conducted from September 2025 to May, 2026 to isolate, molecularly detect, and identify the circulating serotypes of FMDV in cattle populations from outbreak cases in selected areas of Kellem Wollega, West Wollega and East Wollega zone, Western Ethiopia. Purposive sampling was used to select outbreak sites based on occurrence of clinically suspected FMD cases during the study period. Samples were collected from clinically affected and unvaccinated cattle exhibiting characteristic signs of FMD infection. A total of 32 clinical samples (13 epithelial tissues and 19 oral swab samples) were collected considering their outbreak sites and animal factors. One-step rRT-PCR test was employed to detect 3D (pol) gene of FMDV and antigen detection was performed using sandwich ELISA. PCR positive samples were further inoculated on Baby Hamster Kidney (BHK-21) monolayer cell for virus isolation. Descriptive statistics were applied to calculate the percentages. Out of the 32 samples tested; 10(31.25%) samples where positive for the FMDV using real time PCR targeting 3D gene. From the total of PCR positive samples, 70% (7/10) and (3 /10, 30%) were epithelial tissue and oral swab samples, respectively. Furthermore, serotype O was identified in all rRT-PCR positive samples subjected to antigen detection by using sandwich ELISA. 90% (9/10) of the PCR positive samples were able to show cytopathic effects up on adapting them onto BHK-21 cell line. This study revealed that FMD serotypes O were the causality for the outbreak cases of the FMD virus in the study settings. The virus was detected mainly from clinically affected cattle that had no vaccination history, indicating that disease is circulating in cattle in these areas and they are highly susceptible to FMD infection. Therefore, regular and timely vaccination strategy is highly important for effective control. Further phylogenetic analysis of the isolates should be carried for effective vaccine development to control of the disease.

Key words: Isolation, Serotype , Molecular, FMDV, Ethiopia