Abstract:
Peste des petits ruminants (PPR) is a contagious viral disease of small ruminants that has
been targeted for eradication globally. Thus, this study was meant to explore the field
outbreak of PPR virus and to estimate the sero-prevalence of the disease with the associated
risk factors in sheep and goats in selected districts of West Arsi and Arsi zones of Oromia
regional state, Ethiopia. A cross-sectional study was carried out from November 2022 to
March 2023 on 779 unvaccinated small ruminants (677 sheep and 102 goats). A multistage
sampling technique was employed and two district (Sude and Kofele), five Kebeles from
each districts and three villages from each Kebeles were randomly selected after the number
of village and sample per flock was determined by the sample size formula. A systematic
random sampling technique was employed to select the flocks followed by a species based
strata sampling proportional to size of each flock. Data pertaining to the risk factors were
collected by a questionnaire format after an oral informed voluntary consent was obtained
from the respective animal owners in a face to face interview and observation. Blood sample
was collected and tested by c-ELISA. Factors associated with the occurrence of PPR were
identified using binary and multivariable logistic regression. Associations were reported by
odds ratio with 95% confidence interval. Outbreaks of PPR were explored up on a successive
molecular test on swab samples collected from the ocular and nasal area of representative
clinical cases in the flock. Morbidity, mortality and case fatality rate of the clinical disease
were also estimated. The overall seroprevalence of PPR was 12.19% (95% CI: 10.0-14.7%).
Small ruminants in large flock size (AOR = 2.56, 95%CI: 1.38-4.76), brought in to the flock
(AOR=3.68, 95%CI: 1.06-12.76), inter flock contact (AOR=2.68, 95%CI: 1.23-5. 85),
presence of newly introduced animal (AOR = 8.60, 95%CI: 2.38-31.10) and small ruminants
from midland area (Sude district) (AOR=5.70, 95%CI: 3.30-9.54) were at higher risk of
becoming seropositive to PPR than their counterparts. Five PPR outbreaks were occurred in
the study area and resulted; 62.6% morbidity, 19% mortality and 30.3% case fatality rate in
the affected flock. 23 clinical cases of PPR were subjected for sampling after a Pen side test
(PST). Off which 100%, 48% and 16% of them found positive up PST, ic-ELISA and RT PCR, respectively. The finding depicts the existence of PPR virus circulating in the entire
study area. Thus, future studies on the identification of virus lineage and continuous
monitoring and surveillance is deemed necessary towards the control and its eradication
