Abstract:
Metacestodes, the larval stages of canid cestode parasites, are among the causes of morbidity, mortality and financial losses in small ruminants in Ethiopia as a result of organ and carcass condemnation at
slaughter. Several studies have been conducted over the years; however, these studies often had limited
scope and coverage. This systematic review and meta-analysis was conducted to collate the information
so far available in order to provide a pooled prevalence estimate at national level and identify potential predictors. Published and grey literature written in English and Amharic in the period from, 1st of
January 1990 to June 25, 2015 were searched from electronic databases and repositories of academic
and research institutions. Relevant animal level data on 67,743 small ruminants was extracted from 23
published articles and one master’s thesis resulting altogether in 86 animal level reports that conformed
to predefined criteria. The dataset was analyzed using a meta-analytical approach. The pooled prevalence
estimate computed for metacestodes infection was 11.8% with a 95% confidence interval (CI) of 9.1, 15.4.
The highest prevalence estimate 31.2% (95% CI: 23.1, 40.9) was found for Cysticercus tenuicollis (Taenia
hydatigena) followed by cystic echinococcosis (Echinococcus granulosus) 8.8% (95% CI: 5.8, 13.1), Cysticercus ovis (Taenia ovis) 4.9% (95% CI: 2.9, 9.4) and Coenurus cerebralis (Taenia multiceps) 4.6% (95% CI: 1.6,
12.2). Among the predictors considered for heterogeneity analysis only sample size and metacestode
type fitted the final multivariable meta-regression model and explained 26.3% of the explainable heterogeneity between studies (p<0.05). The prevalence was noted to decrease with increasing sample size.
No significant difference in prevalence was observed between sheep and goats (p>0.05). In conclusion,
this review showed a widespread occurrence of metacestodes in small ruminants in Ethiopia. Thus, a
holistic approach to break the life cycle of these parasitic stages is suggested, including regulatory interventions that encourage dog owners to keep their dogs confined and prevent backyard slaughter and
proper management of abattoir waste disposal.
