SPATIAL AND TEMPORAL DISTRIBUTION OF FOOT AND MOUTH DISEASE OUTBREAKS IN WEST HARARGHE ZONE, EASTERN ETHIOPIA

Abstract

Foot and mouth disease (FMD) is an economically important trans-boundary viral disease of cloven hoofed animals caused by foot and mouth disease virus belonging to the genus Aphthovirus and family Picornaviridae. It is a well-established endemic disease in Ethiopia since it was first detected in 1957. A ten year (January 2011-December 2020) retrospective study was undertaken with the objective of identifying the spatial and temporal distribution and to forecast the future patterns of FMD outbreaks in West Hararghe Zone (WHZ) of Eastern Ethiopia using data from outbreak reports obtained from Hirna Regional Veterinary Laboratory. A total of 45 FMD outbreaks were reported to occur in WHZ between 2011 and 2020 with an average and median of 4.5 and 3.5 outbreaks per year, respectively. In that period, FMD outbreak was reported at least once in each district of the Zone. The average incidence of FMD outbreaks at district level was 1.12 district year. The incidence differed among districts, the lowest being in Anchar (0.68/10 district year) and highest in Chiro town (1.77/10 district year). The long-term trend of FMD outbreaks indicated a statistically significant increase over 10 years period (p<0.001). The number of outbreak reached at its peak in March and the lowest in June to August. The occurrence of FMD outbreak was found to be seasonal whereby the numbers of outbreaks were relatively higher during dry season (December to March). The spatial and temporal distribution identified in this study showed those risky areas that are prone to the occurrence of FMD outbreaks and the time period in which they predominantly occur. The unregulated and frequent animal movements could have been the likely causes of the increased number of outbreak occurrence during the dry season. Therefore, animal movement regulations should be considered for the long-term control of FMD in WHZ.