Getachew Tuli’s research while affiliated with The Pirbright Institute and other places

Brucellosis is a common zoonotic disease affecting livestock and humans globally. The disease is endemic in Ethiopian livestock. This study was conducted to estimate Brucella seropositivity and identify its risk factors in livestock, and practices that may expose pastoralists to the disease. Data were collected from 2133 animals across 149 households (HHs) in Dubti and Amibara districts, Afar region, Ethiopia. Blood samples from livestock and household data were collected, and interviews were conducted on husbandry and dairy consumption practices. Sera were serially tested using the Rose Bengal test and indirect enzyme-linked immunosorbent assay. The overall seropositivity to anti-Brucella antibodies was 8% (95% CI, 6.6-9.2). The antibodies were found in 12.4%, 6.5%, 6%, and 3% of the goats, cattle, camels, and sheep, respectively. Among the HHs, 59.7% had at least one seropositive animal. A mixed-effects logistic regression analysis revealed species and the acquisition of new animals (in cattle and camels), and age and district (in sheep, goats, and cattle) as significant risk factors. Goats, cattle, and camels had significantly higher odds of Brucella seropositivity than sheep (p < 0.05). Seropositivity was significantly higher (p < 0.05) in adults than in young animals, in acquired than in homebred (cattle and camels), and in those with reproductive disorders than those without. Pastoralists lacked knowledge of brucellosis and its modes of transmission, while practices exposing humans and livestock to brucellosis were common. The findings underscore the need for public awareness campaigns and implementation of brucellosis control measures in pastoral systems.

Introduction Brucellosis is a neglected bacterial zoonosis with serious veterinary and public health importance throughout the world. A cross-sectional study on animal brucellosis was conducted aiming to estimate seroprevalence and molecular detection. Methods Blood samples were collected from a total of 4274 individual animals (cattle, small ruminants and camel) from 241 herds/flocks for serology and PCR. Serum samples were tested using multispecies I-ELISA. Blood clots from seropositive animals were also tested for brucellosis via PCR. Additionally, 13 vaginal swab samples were collected from animals (2 from bovine and 11 from small ruminants) with recent abortion history for bacterial isolation and molecular detection. Results The overall individual animal and herd level seroprevalence was 3.95% (169/4274) and 18.26% (44/241) respectively. The animal level seroprevalence at species level was 1.58% (47/2982), 8.89% (97/1091) and 12.44% (25/201) in bovine, small ruminants (sheep and goat) and camel, respectively. Herd level seroprevalence were 5.43% (10/184), 52.08% (25/48) and 100% (9/9) in bovine, small ruminant and camel, respectively. The animal level seroprevalence of bovine from intensive and extensive systems was 1.10% (31/2808) and 2.87% (5/174) respectively. Blood clots tested for brucellosis via PCR were negative by RT-PCR. Brucella species was isolated from 6/13 (46.15%) vaginal swab samples cultured on Brucella selective agar, and shown to be B. melitensis using Real-Time PCR. Conclusion Overall, seropositivity for camels was higher than what has been reported previously. Also, there was a notable difference in this study in cattle seroprevalence when comparing extensive with intensive systems, with the extensive system having much greater seropositivity.

Background: Brucellosis is one of the most frequent contagious neglected bacterial diseases with serious veterinary and public health importance throughout the world. A cross-sectional study on animal brucellosis was conducted from October 2018 to July 2019 in southern and central Ethiopia with the objective of estimating seroprevalence and molecular detection. Blood samples were collected for serum extraction from a total of 4274 individual animals (cattle, small ruminants and camel) from 241 herds/flocks. Blood clots from seropositive animals were also tested for brucellosis via molecular techniques. Additionally, 13 vaginal swab samples were collected from animals with recent abortion history for bacterial isolation and molecular detection. Results: The extracted serum samples were tested using multispecies I-ELISA and the overall individual animal and herd level seroprevalence was 3.95% (169/4274) and 18.26% (44/241) respectively. The animal level seroprevalence at species level was 1.58%, 8.89%, 12.44% in bovine, small ruminants (sheep and goat) and camel, respectively. Herd level seroprevalence were 5.43%, 52.08%, 100% in bovine, small ruminant and camel, respectively. The animal and herd level seroprevalence of bovine from intensive and extensive systems was 1.1%, 2.87% and 9.2%, 50.00% respectively. Brucella species was isolated from 6/13 (46.15%) vaginal swab samples cultured on brucella selective agar, and shown to be B.melitensis using Real-Time PCR. All of the blood clots from seropositive animals were negative for the presence of Brucellaspp with PCR. Conclusions: In the regions sampled animals in all three categories – cattle, sheep/goats, and camels – mostly had low seroprevalence rates for brucellosis, without great differences from previous serosurveys done in Ethiopia. However, seropositivity for camels was higher than what has been reported previously. Also, there was a notable difference in this study in cattle seroprevalence when comparing extensive with intensive systems, with the extensive system being much higher.

Contagious bovine pleuropneumonia (CBPP) is an infectious and highly contagious respiratory disease of cattle and water buffalo, which is caused by the Mycoplasma mycoides subspecies mycoides small colony. It induces significant economic losses and leads to a serious food security problem, negatively influencing peoples' livelihoods in affected countries. The disease has been reported in different parts of Ethiopia with prevalence ranging from 1.78 to 96%. However, there is not enough epidemiological information about CBPP in the northwestern part of the country, particularly in North Gondar Administrative Zone. This cross-sectional study, therefore, was conducted in four selected districts (Metema, Alefa, Quara, and Dembia) of North Gondar Administrative Zone to detect the incursion and estimate the seroprevalence of CBPP and to identify the potential predisposing factors associated with the spread and occurrence of CBPP in the area. A total of 751 serum samples were collected from 41 herds (villages) having no history of CBPP vaccination. Information like age, sex, breed, herd size, and management were collected during blood sample collection. Data related to agro-climatic zone, trade trekking route from or through CBPP endemic/epidemic zone, transhumance grazing route, vehicle route, and bordering with CBPP epidemic/endemic zone were obtained from district agricultural offices. The serum was screened for CBPP using competitive enzyme-linked immunosorbent assay (c-ELISA) test. The animal level and herd level apparent seroprevalences were 12.92% (95% CI: 10.70–15.52) and 65.85% (95% CI: 49.57–79.10), respectively. The true animal level and herd level prevalences were estimated at 20.13% (95% CI: 16.64–24.21) and 65.22% (95% CI: 48.64–78.72%), respectively. At the animal level, trekking route from or through CBPP endemic/epidemic zone to the study area [OR = 4.77 (95% CI: 1.92–11.84) compared to without trekking route] was identified as the most important risk factor for CBPP spread and seropositivity. In general, epidemiological evidence of the present study indicates that CBPP is a prevalent disease, and animal trekking is an important risk factor for spread of the disease in the study area. This needs due attention from the government and other concerned bodies for its prevention and control to mitigate its economic impact.

Background: Brucellosis is a contagious bacterial zoonotic disease that has economic importance. The disease causes abortion, sterility in male animals, transmitted from animal to animal by contact, and distributed worldwide. Methods: A cross-sectional study design was conducted from

Background Brucellosis is one of the major zoonoses globally with great veterinary and public health importance, particularly in developing countries where people are having frequent contact with livestock and animal products. This cross sectional study was carried out from November 2013 to May 2014 to determine the seroprevalence and assess the potential risk factors of brucellosis in abattoir workers of five export abattoirs at Debre Ziet and Modjo, Central Ethiopia. Methods Serology and structured questionnaire were the methods used. In this study, 156 abattoir workers participated in the questionnaire survey and among them, 149 agreed for blood sample collection. Rose Bengal Plate Test and Complement Fixation Test were conducted using sera samples at serology laboratory of the National Animal Health Diagnostic and Investigation Center. Data collection sheets were used to gather information on possible risk factors believed to influence the spread of Brucella infection in abattoir workers such as sex, age, marital status, duration on job, types of work, educational level, etc. and further information obtained include knowledge of brucellosis and other zoonotic diseases infection, symptoms of the disease, milk and meat consumption habits and work related risk factors. Chi-square and Fisher’s exact tests were used for data analysis. ResultsThe overall seroprevalence of brucellosis in abattoir workers was found to be 4.7 and 1.3% using Rose Bengal plate test and Compliment fixation test, respectively. Based on the questionnaire survey, 66 (44.2%) and 85 (53.21%) of abattoir workers were aware of brucellosis and other zoonotic diseases, and 29 (18.6%) and 21 (13.5%) were using gloves and cover their mouth while slaughtering, respectively. Conclusion Brucellosis in abattoir workers could be prevented by using protective closing and measures. Concerned body should educate occupationally exposed groups and the general public regarding e prevention and control of brucellosis and other zoonotic diseases.

Contagious bovine pleuropneumonia (CBPP) is one of the most important threats to cattle health and production in Ethiopia. At the livestock farm of the Bako Agricultural Research Center, an outbreak of respiratory disease of cattle occurred in May 2011, and many animals were affected and died before the disease was diagnosed. Therefore, this study was designed to determine the seroprevalence of CBPP antibodies in selected districts of Western Oromia Region and to assess the potential risk factors for the occurrence of the disease. A crosssectional study was conducted from November 2013 to March 2014 in three selected districts of Western Oromia Region. A total of 386 sera were examined for the presence of specific antibodies against Mycoplasma mycoidesmycoides small colony (MmmSC), using a competitive enzyme-linked immunosorbent assay. The risk factors that were evaluated in this study were geographical location, age, sex, breed and body condition. The overall seroprevalence in this study was 28.5%. The seroprevalence of Mycoplasma mycoidesmycoides small colony antibodies at the district level was 40.3%, 19.0% and 5.7% in Gobbu Sayyo, BakoTibbe and Horro districts, respectively. There was a statistically significant variation ( p < 0.05) in the prevalence of antibodies amongst the districts. However, animal-related risk factors, such as age, sex, breed and body condition, were not significantly associated ( p > 0.05) with the serological status of the animal. This study showed that the overall prevalence of CBPP in Western Oromia Zones was high. This warrants the implementation of appropriate preventive and control measures to minimise the economic losses associated with the disease. Keywords: Seroprevalence, CBPP, risk factors, c-ELISA, Western Oromia Zones, Ethiopia

A cross-sectional study was conducted in Asella and Bishoftu towns of Oromia Regional State of Ethiopia to determine seropositivity and associated risk factors exposing dairy cattle to brucellosis from December, 2013 to March, 2014. A total of 570 dairy cattle from 35 herds were purposely selected for inclusion in the study based on abortion history. From 35 farms studied, 80, 55.56 and 100% of the farm owners in small, medium and large herd sizes responded as they were aware of brucellosis, respectively. It was also found out that all farm owners of the study area were dependent on culling of the known Brucella infected animals, while most of the farm owners dispose the after birth to open dump in small and medium herd size farms. All sera sample collected were tested and confirmed serologically using the card test (CT), rose Bengal plate test (RBPT), indirect enzyme linked immuno sorbent assay (i-ELISA) and complement fixation test (CFT). Out of 570 samples tested in the present study, an overall sero prevalence was estimated 1.4% (95% CI: 0.241, 3.461) by complement fixation test (CFT). Among the tested samples, 13 (2.28%), 15 (2.63%) and 16 (2.81%) were found positive by the aforementioned tests, respectively. The higher seroprevalence, 3.23% (95% CI: 3.0, 7.4) was observed in Asella compared to Bishoftu (0.52%) town. A Chi-square computed statistical analysis indicated that origin (χ2=6.63; P<0.05), breed type (χ2= 8.49; P<0.05), abortion history (χ2=92.43; P<0.001) and abortion period (χ2=192.97; P<0.001) were the major risk factors for Brucella infection in the study areas. Multivariable logistic regression statistical analysis revealed that origin and breed type were significantly associated with Brucella seropositivity (P<0.05). Consequently, origin was statistically identified to be the major risk factor for brucellosis to occur in relation to other factors (OR=7.56). In conclusion, the prevailing Brucella seropositivity in most of the dairy farms of the study areas signifies the economic importance of brucellosis in the dairy cattle industry and the potential public health implication for human population. Therefore, more proactive measures should be taken to protect the cattle populations from Brucella infection to reduce its economic impact to the dairy industry and the risk of zoonotic infection in exposed human population in the study areas. Key words: Asella, Bishoftu, brucellosis, dairy cattle, seropositivity, risk factors.

A cross-sectional study was conducted in two districts in Arsi zone and one district in East Shoa zone, Ethiopia, to determine seroprevalence and assess the possible risk factors associated with small ruminant brucellosis. A total of 840 blood samples (409 sheep and 431goats) were collected. All sera samples were screened by modified Rose Bengal Test (mRBT) and all positive reactors were further tested by indirect enzyme linked immunosorbent assay (iELISA) test for confirmation. All 39 (4.6%) mRBT positive samples tested positive in iELISA. The individual animal and herd level seroprevalences of small ruminant brucellosis in the study area were 4.6 and 26%, respectively. Individual animal and herd level seroprevalences were highest in Adami Tulu-Jido Kombolcha district in East Shoa and lowest in Dodota Sire district in Arsi zone but differences were not statistically significant. In univariate logistic regression, statistically significant difference in seropositivity were found between different age groups, pregnancy status and parity number but not between flock size, species and sex. Upon multivariate logistic, regression analysis parity and pregnancy status remained significant. A survey among 80 owners revealed general lack of awareness of the disease and showed that they practiced improper handling, disposal of aborted materials and consumption of raw milk as potential risk behaviours. Hence, the study suggests the need for implementing control measures and raising public awareness on prevention methods of the disease.

Brucellosis is a global zoonotic disease and major public and animal health problem in many parts of the world, particularly in places where livestock is a major source of food and income. This cross-sectional study was conducted between November 2012 and May 2013 to determine the seroprevalence and assess potential risk factors of brucellosis in small ruminants in five export abattoirs at Debre Ziet and Modjo, Oromia Regional State, Ethiopia. Serology and questionnaire were the methods used. In this investigation, 853 sera samples of 485 caprines and 368 ovines brought for slaughter were selected randomly. The Rose Bengal plate test and complement fixation test were conducted using sera samples at National Animal Health Diagnostic and Investigation Center (NAHDIC) serology laboratory. Data collection sheets were used to gather information on possible risk factors believed to influence the occurrence of Brucella infection in small ruminants such as age, species, breed, body condition score, and origin of small ruminants. Brucellosis was found in 17 (1.99%) and 15 (1.76%) small ruminants using the Rose Bengal plate test and complement fixation test, respectively. The univariate and multivariate logistic regression analysis showed that age and body condition score of the animals were risk factors to Brucella infection (p = 0.008 and p = 0.001, respectively) in small ruminants. Based on this survey, brucellosis is a potential problem in small ruminants in Ethiopia that should be further explored.