Seroprevalence of Bovine Brucellosis in Ethiopia: Systematic Review and Meta-Analysis

Herd and animal level seroprevalence and associated risk factors of small ruminant brucellosis in the Korahey zone, Somali regional state, eastern Ethiopia

Introduction

Brucellosis is a zoonosis of major public health and economic importance that is endemic in livestock in Ethiopia with varying levels of seroprevalence.

Methods

A cross-sectional study was carried out to determine the individual and herd-level seroprevalence of brucellosis in small ruminants in the Korahey zone of the Ethiopian Somali Region. A total of 324 sera from 63 herds of small ruminants were collected randomly using a multistage sampling technique and the sera were tested using the Rose Bengal Plate Test, and seropositive reactors were confirmed by the Complement Fixation Test.

Results and discussion

The seroprevalence of brucellosis at the herds and the individual level was 6.35% (95% CI: 0.0-13%) and 1.23% (95% CI: 0.0-2%), respectively; with 1.4% in goats and 0.9% in sheep. Moreover, predicted variables like age group, parity, history of abortion, fetal membranes, herd size, ownership of other livestock species, contact with wild animals in the past year, the introduction of new animals in the past year, and lending of breeding males in the past year were not significantly associated (p > 0.05) with Brucella seropositivity at individual and herd level seroprevalence during multivariable logistic regression analysis. Pastoral community awareness regarding the public health impact of brucellosis and the promotion of an intersectoral One Health approach for the effective control of brucellosis is recommended.

Brucellosis and One Health: Inherited and Future Challenges

One Health is the collaborative efforts of multiple disciplines to attain optimal health for people, animals and the environment, a concept that historically owes much to the study of brucellosis, including recent political and ethical considerations. Brucellosis One Health actors include Public Health and Veterinary Services, microbiologists, medical and veterinary practitioners and breeders. Brucellosis awareness, and the correct use of diagnostic, epidemiological and prophylactic tools is essential. In brucellosis, One Health implementation faces inherited and new challenges, some aggravated by global warming and the intensification of breeding to meet growing food demands. In endemic scenarios, disease awareness, stakeholder sensitization/engagement and the need to build breeder trust are unresolved issues, all made difficult by the protean characteristics of this zoonosis. Extended infrastructural weaknesses, often accentuated by geography and climate, are critically important. Capacity-building faces misconceptions derived from an uncritical adoption of control/eradication strategies applied in countries with suitable means, and requires additional reference laboratories in endemic areas. Challenges for One Health implementation include the lack of research in species other than cattle and small ruminants, the need for a safer small ruminant vaccine, the need to fill in the infrastructure gap, the need for realistic capacity-building, the creation of reference laboratories in critical areas, and the stepwise implementation of measures not directly transposed from the so-called developed countries.

Systematic map of the most recent evidence (2010-2019) on ruminant production-limiting disease prevalence and associated mortality in Ethiopia

Background

Ethiopia's livestock sector supports the livelihoods of millions of smallholder farmers. However, despite the improvements of recent years, livestock productivity remains low due to critical constraints, including infectious diseases. The aim of this study was to collate and synthesize the published evidence on ruminant disease frequency and disease-associated mortality in Ethiopia, by identifying knowledge gaps and clusters in the literature to provide the basis for a decision-making tool.

Methods

Searches on both bibliographic and organization databases were conducted in English and were restricted to the period 2010-2019. Search results were screened for relevance at title, abstract and full text level.

Results

There were 716 articles identified relevant to the research question. The systematic map revealed an increased publication output from 2012-2017, compared to 2010-2011 and 2018-2019. Most studies were conducted in Oromia, Amhara and SNNPR. A substantial body of evidence was found for trypanosomosis, ectoparasite infestation, fasciolosis, nematodiasis, echinococcosis, and brucellosis.

Conclusion

This study suggests that despite the high output of epidemiological publications, further understanding of a considerable number of diseases is required and where evidence is abundant, synthesis of information should be carried out in order to better inform decisions on disease control priorities in the livestock sector.

Seroprevalence of human brucellosis in selected sites of Central Oromia, Ethiopia

Brucellosis is one of the most neglected zoonotic diseases in the world. It affects all age groups and both sexes. A cross-sectional study was conducted from December 2019 to May 2020 to estimate the seroprevalence and assess the potential risk factors of brucellosis among dairy cow owners and dairy farmworkers, and assess their knowledge, attitudes, and practices in selected sites in the central highlands of Oromia, Ethiopia. A structured interview question was administered to 284 respondents, and only 166 of them volunteered to give a blood sample. Most respondents had limited knowledge of brucellosis (93.3%), zoonotic diseases transmitted by handling animal delivery (88%), and consuming raw milk and other animal products (90.0%). Accordingly, 149 blood samples from animal owners and 17 farmworkers were collected for serological testing. The serum samples collected were initially screened using the Rose Bengal Plate test, and the Complement Fixation test was used as a confirmatory test. The overall seroprevalence of zoonotic brucellosis was 1.2% (95%CI: 0.32-4.27). There was a statistically significant association of human brucellosis with human housing (OR = 1.8, p = 0.002), contact with aborted fetus (OR = 21.19, p = 0.017), drinking raw milk from non-aborted (OR = 24.99, p = 0.012), aborted (OR = 5.72, 0.019), and retained fetal membrane (OR = 4.22, p = 0.029) cows. In conclusion, the present study revealed that the seroprevalence of brucellosis in the study area was low. Public awareness among animal owners, farm and animal health workers on the transmission and health hazards of brucellosis needs to be addressed through community training. Implementing one health approach between veterinary and medical health professionals must be strengthened.