Seroprevalence and serotype distribution of foot and mouth disease virus and associated risk factors in cattle across various export livestock sourcing districts of Bale Zone, Ethiopia.

Abstract

Background: Foot and mouth disease (FMD) is a contagious and economically important viral disease affecting cloven-hoofed animals. A cross-sectional study was conducted from January to March 2022 in selected districts of Bale zone, Ethiopia to determine the seroprevalence and serotypes of FMD virus circulating in cattle. Blood samples were collected from cattle and tested for antibodies against non-structural proteins (NSP) of FMD virus using a 3ABC enzyme-linked immunosorbent assay (ELISA). Positive samples were further tested for serotype-specific antibodies using solid phase competitive ELISA (SPCE). Descriptive statistics, both univariable and multivariable logistic regression were used to analyse FMD serostatus and associated risk factors.

Results: A total of 962 cattle sera were tested and 200 samples, 20.8% (95% CI: 18.3-23.5) were positive for antibodies against NSP of the FMD virus. The highest seroprevalence was observed in the Seweyna district (35.2%, 95%CI: 26.8-44.7) and the lowest in the Dinsho district (13.0%, 95% CI: 9.5-17.5). The seroprevalence of FMD virus antibody was significantly associated with district (P < 0.05). The seroprevalence among different age groups was statistically significant (P < 0.05). The odds of FMD infection for males was 0.76 (95% CI: 0.534-1.082) compared to females, indicating that male cattle have a lower risk for FMD infection. Out of 200 samples tested for serotype O, A, SAT 1, and SAT 2, 85(43%) were found to have serotype O, 59(30%) serotype A, 142(71%) serotype SAT 1, and 75 (38%) serotype SAT2. Furthermore, multiple FMD serotypes were observed in 15-40% (30-80) of animals tested.

Conclusions: Serotype-specific antibodies against the FMD virus indicate the occurrence and distribution of serotypes O, A, SAT1, and SAT2 in cattle across various districts of the Bale zone in Ethiopia. These findings also highlight the importance of continuously monitoring the seroprevalence of FMD virus serotypes circulation in export livestock sourcing areas. The results indicated that four FMD virus serotypes were distributed across the studied districts. This study supports the inclusion of all four FMD serotypes in vaccine production.