Gezahegne Mamo

Background: Milkborne zoonotic diseases pose a substantial but underrecognized threat to public health, food safety, and milk production in Ethiopia. The risk is amplified by widespread informal dairy markets, habitual consumption of raw milk, and fragmented surveillance across human and animal health sectors. Given constrained resources and the complexity of zoonotic transmission along the milk value chain, disease prioritization is essential for timely interventions and policy action.,Methods: We used MultiCriteria Decision Analysis (MCDA) framework to prioritize milkborne zoonotic disease in this study. We convened multisectoral workshop that brought together twenty-eight experts from human and animal health, environmental sectors, academia, research institutions, NGOs and international partners. Fifteen milkborne zoonotic diseases and aflatoxin exposure were evaluated against five predefined criteria. Raw scores were normalized and aggregated using weighted sums to produce the final ranked list with criteria derived from a structured pairwisecomparison process. Disease scoring drew on an extensive literature review and expert consensus.,Results: The prioritization identified Shiga toxinproducing Escherichia coli (STEC), brucellosis, zoonotic tuberculosis, nontyphoidal salmonellosis, and listeriosis as the top five milkborne zoonotic diseases in Ethiopia. These diseases scored highly on severity, epidemic potential, and economic impact. Midranked conditions included Staphylococcal infections, campylobacteriosis, Rift Valley fever (RVF), and aflatoxin exposure, reflecting moderate but contextspecific importance. Lowerranked diseases (cryptosporidiosis, zoonotic chlamydiosis, hepatitis E) had lower final scores, suggesting either limited milkassociated burden or substantial data gaps.,Conclusion: Prioritizing milk-borne zoonotic diseases provides a foundation for strengthening prevention and control efforts within Ethiopia’s dairy value chain. The findings of this study offer evidence to guide surveillance priorities, risk reduction interventions, and improved milk hygiene and safety practices across formal and informal dairy markets in Ethiopia,K

Accurate prevalence estimation is crucial for effective bovine tuberculosis (bTB) control, as unreliable data often gives rise to strategic failures, misallocation of resources, and loss of stakeholder trust. In an epidemiological study, obtaining true prevalence (Tp) requires accounting for misclassification and measurement errors inherent in diagnostic testing. Given the imperfect specificity and sensitivity of single intradermal comparative tuberculin tests (SICCTT), Bayesian methods present a natural way to propagate these uncertainties. This study uses a Bayesian approach to improve bTB prevalence estimates from imperfect diagnostic tests. It transforms raw screening data from a dairy farm case study into reliable evidence for better veterinary decisions and targeted disease control policies. Prior sensitivity estimates of SICCTT under standard and severe interpretations were 70.0% (BPI: 52.0%–84.6%) and 78.68% (BPI: 62.1%–90.5%), with corresponding specificities of 96.4% (BPI: 92.2%–98.8%) and 94.7% (BPI: 91.4%–97.1%). Posterior estimates showed a slight reduction in sensitivity under standard interpretation (68.3%, BPI: 50.4–83.7), while other estimates remained comparable to prior distributions. Bayesian modeling revealed notable variation in Tp across testing rounds. Rounds 1 and 3 had the highest prevalence, 27.6% (BPI: 18.5–40.6) and 30.9% (BPI: 23.3–47.5) under standard interpretation, respectively. In contrast, test round 4 yielded the lowest prevalence estimate at 4.1% (BPI: 0.6–8.6). The posterior probability of Tp being below 1%, the threshold for herd freedom from M. bovis infection, was 0% for the first three test rounds, but increased to 5.8% in test round 4. Comparative analysis of estimation methods showed that Bayesian estimators with informative priors produced slightly higher point estimates for Tp than the Rogan–Gladen estimator and Bayesian models with uninformative priors, except in test round 3. However, Bayesian estimation with informative priors exhibited wider credible intervals and strong coverage, reflecting the added uncertainty from not fixing test sensitivity and specificity. Convergence diagnostics, including trace plots, autocorrelation function (ACF) plots, and Gelman–Rubin statistics, confirmed adequate mixing and stationarity of the Markov chains, indicating satisfactory performance of the Markov Chain Monte Carlo (MCMC) algorithms. Rapid autocorrelation decay and the stabilization of Gelman–Rubin statistics near 1.0 provide evidence that the posterior samples adequately represent the target distributions. In conclusion, classic apparent prevalence estimates are overly precise when uncertainty around test performance is high. These Bayesian approaches provide a more accurate estimate of bTB prevalence in the study herd and provide baseline data for future Tp estimates using linked combined data.

Sub-Saharan Africa has long been prone to widespread mosquito-borne diseases affecting both humans and animals. However, the presence and impact of West Nile virus (WNV) among livestock in Ethiopia have not been thoroughly investigated. The objective of this study was to investigate the seroprevalence of West Nile virus in livestock in the Afar region using serological methods. A total of 736 serum samples were collected from 224 cattle, 155 camels, 144 sheep, 121 goats, and 92 donkeys in the Amibara and Haruka districts of the Afar region selected using haphazard sampling. Among 736 tested livestock serum samples, 50.7% (373/736) showed anti-WNV IgG antibodies evaluated using the ID screen^® WNV competition multispecies ELISA kits (95% CI: 47–54.4%; p < 0.01). The seroprevalence was higher (p < 0.01) in donkeys (76.1%), followed by camels (69.1%), cattle (52.2%), goats (34.7%), and sheep (25.7%). The study showed a statistically significant difference of WNV seropositivity between species of animals AOR (1.5), 95% CI (1.038–2.212) (p < 0.01). Compared with sheep, donkeys had a seven-fold higher chance of being seropositive for WNV infection (OR: 6.447, 95% CI = 3.888–10.688) (p < 0.01). This study emphasizes how common WNV infection is in Ethiopia’s pastoral Afar region. It is imperative to consider consistent surveillance of WNV infection and prompt management of identified WNV disease in clinical practice. A clear need exists to build additional research capacity regarding WNV infections among both humans and animals.

Our world has been threatened by numerous emerging and reemerging pathogenic diseases; these diseases are seriously affecting the well‐being of human, animal health, and animal production. Most of them are zoonotic diseases and have great veterinary and public health impact, particularly in developing countries where people are having daily frequent contact with livestock and animal products. Brucellosis is one of them. A cross‐sectional study aimed to determine the seroprevalence and associated risk factors of swine brucellosis was carried out at Batu, Alage, and Naka village using serological tests. Accordingly, a total of 196 pigs were included in the study. Rose Bengal Plate Test (RBPT) prepared from the smooth strain B. abortus antigen was used as a screening test, whereas Complement Fixation Test (CFT) was the confirmatory test for swine brucellosis. The results of the present study indicated that, of the total 196 serum samples from pigs, 10 (5.1%) were found to be positive by RBPT and 7 (3.6%) of them were further confirmed by CFT. On the other hand, age and history of obstetrical problems were the major risk factors for overall swine brucellosis seropositivity ( p < 0.05). Thus, the present study suggests that swine brucellosis is prevalent in the study areas and the seropositivity could give an insight that brucellosis could pose public health hazard. Hence, this warrants public education and awareness, and further extensive epidemiological and molecular investigation is recommended.

: Brucellosis is a zoonotic disease with worldwide distribution. In Eritrea, the status of the disease in occupationally exposed dairy farmers is unknown. The objective of this study was to determine the seroprevalence of brucellosis, level of knowledge, and risky practices of dairy cattle owners/workers in Maekel and Debub regions, Eritrea. A cross-sectional study was conducted between August 2021 and February 2022. A total of 416 dairy cattle owners and workers underwent blood collection and interview using a standardized questionnaire. Blood samples were tested using Rose Bengal Plate Test, and positive samples were confirmed using competitive ELISA. Variation in knowledge scores by sociodemographic factors and practices were explored statistically. The apparent and true seroprevalence was 1.2% (95% CI: 0.05–2.8%) and 1.4% (95% CI: 0.6–3.4%), respectively. Apparent seroprevalence was similar in Maekel (1.1%) and Debub (1.2%) regions. Nearly half of the participants (49.5%) had never heard of brucellosis before. Overall, brucellosis knowledge score was low (mean score: 6.53/20). Knowledge score was higher in participants from Maekel region (P P = 0.035), those with higher educational attainment (P = 0.001), and those with more years of experience working in dairy farming (P = 0.001). Knowledge score was lower in farm workers compared with family members (P = 0.016). No significant differences in knowledge score existed between participants who engaged in or did not engage in potential risky practices. In summary, the prevalence of brucellosis in dairy cattle owners/workers in Maekel and Debub regions, Eritrea, was low. Participants demonstrated limited knowledge of brucellosis and engaged in risky practices.

The distribution, epidemiology, and socioeconomic impact of Rift Valley fever (RVF) and West Nile (WN) viruses are poorly known in areas of sub‐Saharan countries like Ethiopian pastoral region. The human and livestock density in the area has increased greatly in recent years, but little work has been done on arboviral diseases and their potential impact on human and livestock health. The aim of this study was to detect the circulation of zoonotic arboviruses such as Rift Valley fever virus and West Nile viruses in the livestock population and to estimate seroprevalence in Afar pastoral area northeast Ethiopia. Cross‐sectional serological survey was carried out in 736 serum samples from which cattle (224), camel (155), goats (121), sheep (144), and donkeys (92) were tested for the presence of anti‐RVFV and anti‐WNV IgG using a competitive enzyme‐linked immunosorbent assay (c‐ELISA) in two purposively selected districts of the Afar region. The present study revealed a 9.1% (95% CI = 8.86–9.29) seroprevalence of co‐circulation of RVF and WNV. High 32/155 (20.7%) seroprevalence of co‐circulation was seen in camels, followed by goat 14/121 (11.6%), cattle 16/224 (7.14%), and sheep 5/144 (3.5%), respectively, and higher 41/421 (9.7%) seroprevalence of co‐circulation was observed in Amibara district than Haruka district. Camels were seven times (OR: 7.016, 95% CI = 2.639–18.653) more likely to be seropositive for the co‐circulation than sheep (p ≤ 0.001). Livestock herds found in Amibara district were 1.2 times (OR: 1.165, 95% CI = 0.680–1.996) more likely to be seropositive for RVFV infection than those in Haruka areas. Given the co‐occurrence of RVFV and WNV circulations, along with often suboptimal human and animal health surveillance in many similar areas’ attention should be given. Investigation of the potential socioeconomic and health impacts of zoonotic arbovirus infections in such areas is crucial. Since both RVFV and WNFV are transmitted through a mosquito vector, avoiding mosquito bites is the primary method of prevention.

Purpose: Brucellosis is one of the most important reproductive diseases that cause abortion and breeding failure in small ruminants in Ethiopia. Therefore, our objective was to detect the seropositivity and risk factors of Brucella infection in small ruminants with history of abortion using modified RBPT, cELISA, and CFT in the Amibara district of the Afar Region, Ethiopia. Methods: Sera were collected from 226 animals (195 goats and 31ewes) and assessed for seropositivity of Brucella infection using modified RBPT, CFT, and competitive ELISA. Results: The overall seroprevalence was 12.0% (27 out of 226), 7.5% (17 out of 226), and 26.5% (60 out of 226) by mRBPT, CFT, and cELISA, respectively. Out of 27 sera that were reactive by mRBPT, 17 (63.0%) were also reactive by (CFT). Out of the 17 sera that were reactive by CFT and mRBPT, 14 (82.4%) were reactive by cELISA. Out of the 29 sera that were non-reactive by both mRBPT and CFT, 10 (34.5%) were found reactive by cELISA. Out of the 226 sera that were tested by both mRBPT and cELISA, 20 (8.9%) were reactive by both tests, while 159 (70.4%) were non-reactive by both tests. The percentage of test agreement (79.2%) between mRBPT and cELISA was poor (k=0.353). High seropositivity for Brucella infection was significantly associated with the presence of retained placenta in the studied animals (adjusted OR=2.2, 95% CI, 1.1– 4.4, P=0.030) as detected by cELISA. Conclusion: The current study revealed that a cELISA-based seroepidemiological survey increases the likelihood of detecting individuals with brucellosis and provides reliable evidence for mRBPT. Furthermore, there was a significant association between seropositivity for Brucella infection and retained placenta. These findings emphasize the necessity for proactive measures to reduce the economic impact of brucellosis and mitigate the risk of zoonotic transmission.

Background: Paratuberculosis, caused by Mycobacterium avium subsp. paratuberculosis (MAP), is a chronic progressive granulomatous enteritis mainly affecting domestic and wild ruminants worldwide. Although paratuberculosis could be prevail in Ethiopia, there is a scarcity of epidemiological data on paratuberculosis in the country. Thus, this study was conducted to estimate the prevalence of paratuberculosis based on gross and microscopic lesions in cattle slaughtered at ELFORA Abattoir, central Ethiopia. Small intestines and associated lymph nodes of 400 apparently healthy cattle which were slaughtered at ELFORA export abattoir were examined for gross and microscopic lesions of paratuberculosis. The microscopic lesions were classified into four grades (I-IV) based on the type and number of cells infiltrated into the lesion. The prevalence of paratuberculosis was estimated on the basis of gross as well as microscopic lesion of paratuberculosis. Results: The prevalence of paratuberculosis was 11.25% (95% Confidence interval, CI = 0.083–0.148) on the basis of gross lesion. However, relatively lower prevalence (2.0%, 95% CI = 0.01, 0.039) was recorded based on microscopic lesion. The gross lesions were characterized by intestinal thickening, mucosal corrugations and enlargement of associated mesenteric lymph nodes. On the other hand, the microscopic lesions were characterized by granuloma of different grades ranging from grade I to grade III lesions. Conclusions: The present study indicated the occurrence of paratuberculosis in cattle of Ethiopia based on the detection of gross and microscopic lesions consistent with the lesion of paratuberculosis. The result of this study could be used as baseline information for future studies on the epidemiology and economic significance of paratuberculosis.

Background: Brucellosis is a contagious, economically significant bacterial disease that affects animals worldwide and is one of the most neglected zoonotic diseases in the world. The disease poses a barrier to the trade of animals and animal products, represents a public health hazard, and is an impediment to free animal movement. Methods: A cross-sectional study was carried out from December 2019 to May 2020 in order to determine seroprevalence and identify potential risk factors for brucellosis in dairy cows in the Central Highlands of Ethiopia with recent cases of abortion. Purposive sampling was carried out on the farms and kebeles in question to screen for recent cases of abortion in dairy cows. For the purpose of performing serological testing, 352 blood samples from dairy cattle were obtained. The Rose Bengal Plate test was used to initially screen the serum samples, and the Complement Fixation test was utilized as a confirmatory test. Results: Using combined RBPT and CFT tests, the overall seroprevalence of bovine brucellosis was 0.6% (95% CI: 0.16– 2.09). Retained fetal membrane (OR = 32.74, p = 0.006), market-based stock replacement (OR = 16.55, p = 0.002), breeding method (OR = 7.58, p = 0.027), and late stage of abortion (OR = 14.74, p = 0.0002) are all significantly associated risk factors. Conclusion: The present seroprevalence study revealed that brucellosis is prevalent at a lower rate among dairy cattle in the study areas. However, there is a possible risk of brucellosis transmission in dairy cattle and the exposed human population in research locations because no control measures were put in place there. Implementing a test and slaughter method with compensation for farmers is advised due to the low prevalence of bovine brucellosis in government-owned and small-holder farms.

Middle East respiratory syndrome coronavirus (MERS-CoV) is enzootic in dromedary camels and causes zoonotic infection and disease in humans. Although over 80% of the global population of infected dromedary camels are found in Africa, zoonotic disease had only been reported in the Arabia Peninsula and travel-associated disease has been reported elsewhere. In this study, genetic diversity and molecular epidemiology of MERS-CoV in dromedary camels in Ethiopia were investigated during 2017-2020. Of 1766 nasal swab samples collected, 61 (3.5%) were detected positive for MERS-CoV RNA. Of 484 turbinate swab samples collected, 10 (2.1%) were detected positive for MERS-CoV RNA. Twenty-five whole genome sequences were obtained from these MERS-CoV positive samples. Phylogenetically, these Ethiopian camel-originated MERS-CoV belonged to clade C2, clustering with other East African camel strains. Virus sequences from camel herds clustered geographically while in an abattoir, two distinct phylogenetic clusters of MERS-CoVs were observed in two sequential sampling collections, which indicates the greater genetic diversity of MERS-CoV in abattoirs. In contrast to clade A and B viruses from the Arabian Peninsula, clade C camel-originated MERS-CoV from Ethiopia had various nucleotide insertions and deletions in non-structural gene nsp3, accessory genes ORF3 and ORF5 and structural gene N. This study demonstrates the genetic instability of MERS-CoV in dromedaries in East Africa, which indicates that the virus is still actively adapting to its camel host. The impact of the observed nucleotide insertions and deletions on virus evolution, viral fitness, and zoonotic potential deserves further study.