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Foodborne bacteria like Escherichia coli threaten global food security, necessitating affordable, on-site detection methods, especially in resource-limited settings. This study optimized loop-mediated isothermal amplification (LAMP) integrated with peroxidase-mimicking G-quadruplex DNA structures (DNAzyme), termed DNAzyme-LAMP which was designed to incorporate two different catalytic DNAzymes per amplification unit, enabling colorimetric detection of E. coli in leafy vegetables and milk samples. Additionally, we introduce a novel electrochemical method that enhances analytical sensitivity. The optimized DNAzyme-LAMP achieved a detection limit below 6.3 CFU per reaction or 0.1 aM gene copies. This system lays the groundwork for the development of on-site biosensors and can be adapted for detecting other foodborne pathogens., Competing Interests: Declarations. Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

Klebsiella species commonly reside in dairy cattle guts and are consistently exposed to beta-lactam antibiotics, including ceftiofur, which are frequently used on the U.S. dairy farms. This may impose selection pressure and result in the emergence of extended-spectrum beta-lactamase (ESBL)-producing strains. However, information on the status and antimicrobial resistance (AMR) profile of ESBL- Klebsiella spp. in the U.S. dairy farms is largely unknown. This study aimed to determine the prevalence and AMR profile of ESBL- Klebsiella spp. and the factors affecting their occurrence in dairy cattle farms. Rectal fecal samples ( n = 508) and manure, feed, and water samples ( n = 64) were collected from 14 dairy farms in Tennessee. Samples were directly plated on CHROMagar ESBL, and presumptive Klebsiella spp. were confirmed using matrix-assisted laser desorption/ionization-time of flight mass spectrometry. Antimicrobial susceptibility testing was performed on the isolates against panels of 14 antimicrobial agents from 10 classes using minimum inhibitory concentration. Of 572 samples, 57 (10%) were positive for ESBL- Klebsiella spp. The fecal prevalence of ESBL- Klebsiella spp. was 7.2% (95% CI: 6.5-8.0). The herd-level fecal prevalence of ESBL- Klebsiella spp. was 35.7% (95% CI: 12.7-64.8). The fecal prevalence of ESBL- Klebsiella spp. was significantly higher in calves than in cows and higher in cows with higher parity (≥3) as compared to cows with low parity ( P < 0.001). Most (96.5%, n = 57) ESBL- Klebsiella spp. were resistant to ceftriaxone. The highest level of acquired co-resistance to ceftriaxone in ESBL- Klebsiella spp. was to sulfisoxazole (66.7%; 38/57). About 19% of ESBL-K lebsiella spp. were multidrug resistant. The presence of ESBL-producing Klebsiella spp. in dairy cattle, feed, and water obtained from troughs could play a crucial epidemiological role in maintaining and spreading the bacteria on farms and serving as a point source of transmission., Importance: We collected 572 samples from dairy farms, including rectal feces, manure, feed, and water. We isolated and identified extended-spectrum beta-lactamase (ESBL)- Klebsiella spp. and conducted an antimicrobial susceptibility test and analyzed different variables that may be associated with ESBL- Klebsiella spp. in dairy farms. The results of our study shed light on how ESBL- Klebsiella spp. are maintained through fecal-oral routes in dairy farms and possibly exit from the farm into the environment. We determine the prevalence of ESBL- Klebsiella spp. and their antimicrobial susceptibility profiles, underscoring their potential as a vehicle for multiple resistance gene dissemination within dairy farm settings. We also collected data on variables affecting their occurrence and spread in dairy farms. These findings have significant implications in determining sources of community-acquired ESBL- Enterobacteriaceae infections and designing appropriate control measures to prevent their spread from food animal production systems to humans, animals, and environments., Competing Interests: The authors declare no conflict of interest.

Introduction: The rising prevalence of Extended-Spectrum Beta-Lactamase (ESBL)-producing Klebsiella species (spp.) poses a significant threat to human and animal health and environmental safety. To address this pressing issue, a comprehensive study was undertaken to elucidate the burden and dissemination mechanisms of ESBL- Klebsiella spp. in dairy cattle farms., Methods: Fifty-seven Klebsiella species were isolated on CHROMagar™ ESBL plates and confirmed with MADLI-TOF MS and whole genome sequenced from 14 dairy farms., Results and Discussion: Six families of beta-lactamase ( bla ) ( bla CTX-M , bla SHV , bla TEM , bla OXY , bla OXA, and bla SED ) were detected in ESBL- Klebsiella spp. genomes. Most (73%) of isolates had the first three types of beta-lactamase genes, with bla SHV being the most frequent, followed by bla CTX-M . Most (93%) isolates harbored two or more bla genes. The isolates were genotypically MDR, with 26 distinct types of antibiotic resistance genes (ARGs) and point mutations in gyrA , gyrB , and parC genes. The genomes also harbored 22 different plasmid replicon types, including three novel IncFII. The IncFII and Col440I plasmids were the most frequent and were associated with bla CTXM-27 and qnrB19 genes, respectively. Eighteen distinct sequence types (STs), including eight isolates with novel STs of K. pneumoniae , were detected. The most frequently occurring STs were ST353 ( n = 8), ST469 ( n = 6), and the novel ST7501 ( n = 6). Clusters of ESBL- Klebsiella strains with identical STs, plasmids, and ARGs were detected in multiple farms, suggesting possible clonal expansion. The same ESBL variant was linked to identical plasmids in different Klebsiella STs in some farms, suggesting horizontal spread of the resistance gene. The high burden and dual spread mechanism of ESBL genes in Klebsiella species, combined with the emergence of novel sequence types, could swiftly increase the prevalence of ESBL- Klebsiella spp., posing significant risks to human, animal, and environmental health. Immediate action is needed to implement rigorous surveillance and control measures to mitigate this risk., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Gelalcha, Mohamed, Gelgie and Kerro Dego.)

Mycoplasma bovis has recently been identified increasingly in dairy cows causing huge economic losses to the dairy industry. M. bovis is a causative agent for mastitis, pneumonia, endometritis, endocarditis, arthritis, otitis media, and many other clinical symptoms in cattle. However, some infected cows are asymptomatic or may not shed the pathogen for weeks to years. This characteristic of M. bovis , along with the lack of adequate testing and identification methods in many parts of the world until recently, has allowed the M. bovis to be largely undetected despite its increased prevalence in dairy farms. Due to growing levels of antimicrobial resistance among wild-type M. bovis isolates and lack of cell walls in mycoplasmas that enable them to be intrinsically resistant to beta-lactam antibiotics that are widely used in dairy farms, there is no effective treatment for M. bovis mastitis. Similarly, there is no commercially available effective vaccine for M. bovis mastitis. The major constraint to developing effective intervention tools is limited knowledge of the virulence factors and mechanisms of the pathogenesis of M. bovis mastitis. There is lack of quick and reliable diagnostic methods with high specificity and sensitivity for M. bovis . This review is a summary of the current state of knowledge of the virulence factors, pathogenesis, clinical manifestations, diagnosis, and control of M. bovis mastitis in dairy cows., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Gelgie, Desai, Gelalcha and Kerro Dego.)

Mastitis is an inflammation of the mammary gland commonly caused by bacteria or fungi. Staphylococcus aureus is a major bacterium that causes mastitis in dairy cows. Non-aureus staphylococci are also increasingly reported, with Staphylococcus chromogenes being the most common species. Current staphylococcal mastitis control programs are not fully effective, and treatment with antibiotics is not sustainable. Non-antibiotic sustainable control tools, such as effective vaccines, are critically needed. We previously developed S. aureus surface-associated proteins (SASP) and S. chromogenes surface-associated proteins (SCSP) vaccines that conferred partial protective effects. We hypothesized that vaccination with SASP or SCSP would reduce the incidence of S. aureus mastitis throughout the lactation period. The objective of this study was to evaluate the efficacy of SASP and SCSP vaccines against S. aureus and non-aureus staphylococcal mastitis under natural exposure over 300 days of lactation. Pregnant Holstein dairy cows (n = 45) were enrolled and assigned to receive SASP (n = 15) or SCSP (n = 16) vaccines or unvaccinated control (n = 14). Cows were vaccinated with 1.2 mg of SASP or SCSP with Emulsigen-D adjuvant. Control cows were injected with phosphate-buffered saline with Emulsigen-D adjuvant. Three vaccine injections were given subcutaneously at 60, 40, and 20 days before the expected calving. Booster vaccinations were given at 120 and 240 days in milk. Cows were monitored for mastitis at quarter and cow levels, staphylococcal mastitis incidence, changes in serum and milk anti-SASP and anti-SCSP antibody titers, bacterial counts in milk, adverse reactions, milk yield and milk somatic cells count over 300 days of lactation. The SCSP vaccine conferred a significant reduction in the incidence of staphylococcal mastitis. Milk and serum anti-SASP and anti-SCSP antibody titers were increased in the vaccinated cows compared to unvaccinated control cows. Anti-SASP and anti-SCSP antibody titers decreased at about 120 days in milk, indicating the duration of immunity of about four months. In conclusion, the SASP and SCSP vaccines conferred partial protection from natural infection., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Introduction: The extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae, such as Escherichia coli , are emerging as a serious threat to global health due to their rapid spread and their multidrug-resistant (MDR) phenotypes. However, limited information is available regarding the prevalence and antimicrobial resistance (AMR) profile of ESBL- E. coli in the United States dairy farms. This study aimed to determine the prevalence and AMR pattern of ESBL- E. coli in East Tennessee dairy cattle farms., Methods: Rectal fecal samples from dairy cattle ( n  = 508) and manure ( n  = 30), water ( n  = 19), and feed samples ( n  = 15) were collected from 14 farms. The presumptive E. coli was isolated on CHROMagar™ ESBL and confirmed by matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS). Antimicrobial susceptibility testing was performed on the ESBL- E. coli isolates., Results and Discussion: From 572 fecal and farm environmental samples, a total of 233 (41%, n  = 572) ESBL- E. coli were identified. The prevalence of fecal ESBL- E. coli was 47.5% (95% CI: 46.2-49.2). The within-farm prevalence of ESBL- E. coli ranged from 8 to 100%. Recent treatment history with third-generation cephalosporins (3GC), cow parity ≥3, and calves were the independent risk factors associated ( P  < 0.05) with fecal carriage of ESBL- E. coli . Overall, 99.6% ( n = 231) ESBL- E. coli tested were phenotypically resistant to at least one of the 14 antimicrobial agents tested. The most common AMR phenotypes were against beta-lactam antibiotics, ampicillin (99.1%; n  = 231 isolates), and ceftriaxone (98.7%, n  = 231). Most ESBL- E. coli isolates (94.4%) were MDR (resistance to ≥3 antimicrobial classes), of which 42.6% showed co-resistance to at least six classes of antimicrobials. ESBL- E. coli isolates with concurrent resistance to ceftriaxone, ampicillin, streptomycin, tetracycline, sulfisoxazole, and chloramphenicol are widespread and detected in all the farms. The detection of MDR ESBL- E. coli suggests that dairy cattle can be a reservoir for these bacteria, highlighting the associated public health risk., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Gelalcha, Gelgie and Kerro Dego.)

Introduction: The rise in extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae in dairy cattle farms poses a risk to human health as they can spread to humans through the food chain, including raw milk. This study was designed to determine the status, antimicrobial resistance, and pathogenic potential of ESBL-producing - E. coli and - Klebsiella spp. isolates from bulk tank milk (BTM)., Methods: Thirty-three BTM samples were collected from 17 dairy farms and screened for ESBL- E. coli and - Klebsiella spp. on CHROMagar ESBL plates. All isolates were confirmed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) and subjected to antimicrobial susceptibility testing and whole genome sequencing (WGS)., Results: Ten presumptive ESBL-producing bacteria, eight E. coli , and two K. pneumoniae were isolated. The prevalence of ESBL- E. coli and - K. pneumoniae in BTM was 21.2% and 6.1%, respectively. ESBL- E. coli were detected in 41.2% of the study farms. Seven of the ESBL- E. coli isolates were multidrug resistant (MDR). The two ESBL-producing K. pneumoniae isolates were resistant to ceftriaxone. Seven ESBL- E. coli strains carry the bla CTX-M gene, and five of them co-harbored bla TEM-1 . ESBL- E. coli co-harbored bla CTX-M with other resistance genes, including qnr B 19 , tet (A), aad A1, aph(3'') -Ib, aph(6) -Id), floR , sul2 , and chromosomal mutations ( gyrA, gyrB, parC, parE, and pmrB ). Most E. coli resistance genes were associated with mobile genetic elements, mainly plasmids. Six sequence types (STs) of E. coli were detected. All ESBL- E. coli were predicted to be pathogenic to humans. Four STs (three ST10 and ST69) were high-risk clones of E. coli . Up to 40 virulence markers were detected in all E. coli isolates. One of the K. pneumoniae was ST867; the other was novel strain. K. pneumoniae isolates carried three types of beta-lactamase genes ( bla CTX-M , bla TEM-1 and bla SHV ). The novel K. pneumoniae ST also carried a novel IncFII(K) plasmid ST., Conclusion: Detection of high-risk clones of MDR ESBL- E. coli and ESBL- K. pneumoniae in BTM indicates that raw milk could be a reservoir of potentially zoonotic ESBL- E. coli and - K. pneumoniae ., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Gelalcha, Mohammed, Gelgie and Kerro Dego.)

Antimicrobial resistance (AMR) is one of the top global health threats of the 21th century. Recent studies are increasingly reporting the rise in extended-spectrum beta-lactamases producing Enterobacteriaceae (ESBLs-Ent) in dairy cattle and humans in the USA. The causes of the increased prevalence of ESBLs-Ent infections in humans and commensal ESBLs-Ent in dairy cattle farms are mostly unknown. However, the extensive use of beta-lactam antibiotics, especially third-generation cephalosporins (3GCs) in dairy farms and human health, can be implicated as a major driver for the rise in ESBLs-Ent. The rise in ESBLs-Ent, particularly ESBLs- Escherichia coli and ESBLs- Klebsiella species in the USA dairy cattle is not only an animal health issue but also a serious public health concern. The ESBLs- E. coli and -Klebsiella spp. can be transmitted to humans through direct contact with carrier animals or indirectly through the food chain or via the environment. The USA Centers for Disease Control and Prevention reports also showed continuous increase in community-associated human infections caused by ESBLs-Ent. Some studies attributed the elevated prevalence of ESBLs-Ent infections in humans to the frequent use of 3GCs in dairy farms. However, the status of ESBLs-Ent in dairy cattle and their contribution to human infections caused by ESBLs-producing enteric bacteria in the USA is the subject of further study. The aims of this review are to give in-depth insights into the status of ESBL-Ent in the USA dairy farms and its implication for public health and to highlight some critical research gaps that need to be addressed.

Enterohemorrhagic Escherichia coli (EHEC) is one of the most common E. coli pathotypes reported to cause several outbreaks of foodborne illnesses. EHEC is a zoonotic pathogen, and ruminants, especially cattle, are considered important reservoirs for the most common EHEC serotype, E. coli O157:H7. Humans are infected indirectly through the consumption of food (milk, meat, leafy vegetables, and fruits) and water contaminated by animal feces or direct contact with carrier animals or humans. E. coli O157:H7 is one of the most frequently reported causes of foodborne illnesses in developed countries. It employs two essential virulence mechanisms to trigger damage to the host. These are the development of attaching and effacing (AE) phenotypes on the intestinal mucosa of the host and the production of Shiga toxin (Stx) that causes hemorrhagic colitis and hemolytic uremic syndrome. The AE phenotype is controlled by the pathogenicity island, the locus of enterocyte effacement (LEE). The induction of both AE and Stx is under strict and highly complex regulatory mechanisms. Thus, a good understanding of these mechanisms, major proteins expressed, and environmental cues involved in the regulation of the expression of the virulence genes is vital to finding a method to control the colonization of reservoir hosts, especially cattle, and disease development in humans. This review is a concise account of the current state of knowledge of virulence gene regulation in the LEE-positive EHEC.

Antimicrobials have been widely used in dairy farms to prevent and control dairy cattle diseases since 1960s. This led to the emergence of antimicrobial resistant bacteria (ARB) that, along with their antimicrobial resistance genes (ARGs), can spread from dairy farms to humans. Therefore, regular antimicrobial resistance (AMR) monitoring is important to implement proper mitigation measures. The objective of this study was to determine the prevalence of AMR and extended-spectrum beta-lactamases (ESBLs)-producing Escherichia coli in dairy cattle. A cross-sectional study was conducted in four dairy cattle farms (A-D) in East Tennessee. A total of 80 samples consisting of 20 samples each of bulk tank milk, feces, dairy cattle manure-amended soil, and prairie soil adjacent to the farms were collected and cultured for the isolation of E. coli . Tetracycline (TET r )-, third-generation cephalosporin (TGC r )- and nalidixic acid (NAL r )-resistant E. coli ( n  = 88) were isolated and identified on agar media supplemented with TET, cefotaxime, and NAL, respectively. TGC r E. coli were tested for ESBLs and other coselected ARGs. TET r (74%, n  = 88) was the most common, followed by TGC r (20%) and NAL r (8%). Farms had significant ( p  < 0.001) differences: the highest prevalence of TGC r (55%) and TET r (100%) were observed in farm D, while all NAL r isolates were from farm C. Over 83% of TGC r isolates ( n  = 18) harbored ESBL gene bla CTX-M . Majority (78%) of the E. coli isolates were multidrug-resistant (MDR), being positive for beta-lactams ( bla CTX-M ), TETs tet ( A ), tet ( B ), tet ( M )), sulfonamides ( sul 2), aminoglycosides ( strA ), and phenicols ( floR ). This study indicated the widespread occurrence of MDR ESBLs- E. coli in dairy cattle farms. AMR surveillance of more dairy farms and identification of farm-level risk factors are important to mitigate the occurrence and spread of ARB of significant public health importance, such as ESBLs- E. coli .

Background: Abortion, causes by several infectious and non-infectious factors is one of the most critical health problems of cattle in Ethiopia. Thus, this study aimed to assess knowledge and perception of the community about potential causes of abortion and case-control study of brucellosis as a cause of abortion in cattle of study districts., Methods: A cross-sectional study was conducted between October 2016 and October 2017 in selected districts of the Jimma zone using a questionnaire survey. Based on the questionnaire survey, we also carried out a case-control study (141 cases and 282 controls) to confirm whether the most frequently mentioned disease (brucellosis) is associated with abortion. The blood samples were collected from both cases and controls cattle groups and then serum was separated. The presence of antibody against Brucella organism in serum was first tested by Rose Bengal Plate Test (RBPT) and all RBPT positive samples were confirmed using the Complement Fixation Test (CFT)., Results: From a total of 180 randomly selected respondents, the majority (59.4%) of them attributed abortion to infectious diseases. Based on the questionnaire survey, brucellosis, leptospirosis and listeriosis were identified as the major infectious causes of abortion in the areas. Physical injuries, shortage of feed and toxic substances were observed as less important non-infection causes of abortion in the study areas. This study also identified improper disposal of aborted materials and birth products, use of communal bulls, sharing communal grazing areas and water sources which favour disease transmission. Exposure to Brucella organism was higher among cases (6.4%) than controls (2.8%) with a statistically significant difference (p = 0.042)., Conclusion: Brucellosis is the most important infectious cause of cattle abortion in this study. Thus, important to conduct appropriate control methods and increasing public awareness of the zoonotic transmission of brucellosis are suggested. This finding also recommended the need for further study to isolate and characterise brucellosis as a cause of abortion in cattle., (© 2021 The Authors. Veterinary Medicine and Science published by John Wiley & Sons Ltd.)

Different breeds of cattle were observed to have a variable degree of susceptibility to bovine tuberculosis (bTB). The screening of bTB was conducted on 720 dairy cattle consisting of three breeds using the single intradermal cervical comparative tuberculin (SICCT) test. Besides this, 43 SICCT test-positive cattle were used to compare the severity of the pathology of bTB among the three breeds and to identify the causative mycobacteria using spoligotyping. The overall SICCT test positivity was 17.92% (129/720) by pooling all animals in the three farms. There was a significant difference in SICCT test positivity among the three breeds (χ 2 = 71.06; p < 0.001); the highest (25.34%) was recorded in the crossbreed followed by the Boran breed (10.08%), while the least (3.14%) was recorded in the Jersey breed. On other hand, the highest median pathology score (10.0, interquartile range, IQR = 6.0-17.0) was recorded in Boran followed by cross (5.0, IQR = 3.5-7.5), while the least (3.0, IQR = 2.25-3.0) was recorded in Jersey. Thus, the difference in the median pathology scores was significant [Kruskal Wallis χ ( 2 ) 2 = 18.78, p < 0.001] among the three breeds. Furthermore, multivariate analysis using ordinal logistic regression by considering age, sex, breed, reproductive status, and location of the farms also showed a significant [ χ ( 2 ) 2 = 11.97, p < 0.01] difference in pathology scores among the three breeds of cattle. Even at a single-herd level at Holeta, the difference in severity of pathology between the Boran and crossbreeds was significant ( U = 33.5; p < 0.01). Culture positivity was 39% in 108 suspicious tissues. Fourteen Mycobacterium bovis ( M. bovis ) and two Mycobacterium tuberculosis ( M. tuberculosis ) were isolated from the lesions. All the 14 M. bovis isolates belonged to SB0912, while the two M. tuberculosis belonged to SIT54. In conclusion, although the frequency of the SICCT test positivity was high in the crossbreed, a more severe pathology was observed on the Boran (zebu) breed. In addition M . tuberculosis was isolated from TB lesions of dairy cattle, demonstrating the role of M. tuberculosis in causing TB in cattle., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Ambaw, Gelalcha, Bayissa, Worku, Yohannis, Zewude and Ameni.)

A participatory epidemiological study was conducted with cattle keepers in Jimma zone, Ethiopia, between October 2018 and October 2019 to identify the causes of abortion in cattle. Data collection involved 20 group discussions (each comprising 8-12 people) in 10 peasant associations. Methods used in group discussions included semi-structured interviews, pairwise ranking, matrix scoring, proportional piling, and seasonal calendar. The result of pairwise ranking identified brucellosis, leptospirosis, listeriosis, trypanosomosis, and Foot and mouth disease (FMD) in decreasing order as the most important causes of abortion in cattle. Mechanical or physical agents were also identified as less important non-infectious causes of cattle abortion in study areas. A very strong agreement (W = 0.880; P < 0.001) was observed among informant groups in pairwise ranking as to the most important cause of cattle abortion in study areas. Proportional piling showed that brucellosis was responsible for the highest proportion of abortions (39.9%) followed by leptospirosis (22.5%) and listeriosis (16.3%). A lesser proportion of abortion was attributed to trypanosomosis and FMD which comprise 11.6% and 9.7%, respectively. Matrix scoring showed strong agreement (W = 0.572 to 0.898; p < 0.001) concerning causes of abortion and its clinical signs between informant groups. According to the discussants, brucellosis and FMD tend to occur more frequently in the winter and spring seasons whereas listeriosis and trypanosomosis occurred frequently in the summer and autumn seasons, respectively. Strong agreement was observed among informant groups about the seasonal pattern of occurrence causes of abortion (W = 0.525-0.794; P < 0.001). Participants used medicinal plants and other traditional practices to manage cattle abortion in their areas. Farmers' knowledge should be incorporated to investigate health problems of unknown causes, designing, and implementing the intervention program in the areas., Competing Interests: The authors declare no conflict of interest., (© 2021 The Author(s).)

Q fever is a zoonotic disease that is caused by Coxiella burnetii and leads to abortion and infertility in ruminants and debilitating disease in humans. Jimma zone, including Jimma town, located in the Oromia region of Ethiopia, was affected by an outbreak of abortions in ruminants related to Q fever infection between 2013 and 2015. This study aimed to investigate the geo-clustering of C. burnetii seroprevalence in dairy farms of Jimma town and identify the environmental risk factors associated with seroprevalence distribution. A total of 227 cattle were tested for antibodies against C. burnetii in 25 farms. We explored the clustering of C. burnetii seroprevalence using semivariograms. A geostatistical regression-based model was implemented to quantify the risk factors and to predict the geographical variation in C. burnetii seroprevalence at unsampled locations in Jimma town using OpenBugs. Our results demonstrated that the risk of exposure in dairy cattle varied across the landscape of Jimma town and was associated with environmental risk factors. The predictive map of C. burnetii seroprevalence showed that communities in the eastern part of Jimma town had the highest risk of exposure. Our results can inform community-level investigations of human seroprevalence in the high-risk areas to the east of Jimma.

Background: Q fever is a zoonotic disease, caused by Gram negative bacterium C. burnetii, which imparts significant socio-economic burden due to production and reproductive loss (abortion, stillbirth, and infertility) in ruminants and debilitating clinical disease in human populations. While sheep and goats are considered the primary reservoirs of infection to humans, infection can also result from exposure to cattle. Recent studies indicate that in Ethiopia Q fever is a disease of growing public health interest. The top cattle producing region in Ethiopia is the Oromia region and Jimma is the zone that ranks first in the population of cattle within Oromia. While in Jimma zone livestock production plays an important role in people's livelihoods and nutrition, to date, there is no available report on seroprevalence of Q fever in cattle. This is particularly important due to the low dairy farm biosecurity in Jimma town. This study aimed to evaluate the potential risk for public health from cattle production; a specific objective of this study included the estimation of the seroprevalence of C. burnetii infection and its potential risk factors in dairy cattle and cattle for slaughter in Jimma Town., Results: The seroprevalence of C. burnetii in cattle present at dairy farms was significantly lower compared to cattle presented at slaughterhouse [6.17% (95% CI: 3.41-10.13) and 11.79% (95% CI: 7.63-17.17), respectively; (P = 0.04)]. As the age of dairy cattle increase by 1 year, they were 1.51 more likely to be positive of C. burnetii [OR = 1.51 (95%CI: 1.30-1.75; (P = 0.000)]. Cattle managed in semi-intensive production systems were 8.08 more likely to be C. burnetii seropositive compared to intensively managed dairy cattle [OR = 8.08 (95%CI: 1.03-63.68); P = 0.047]. Dairy cattle with access to nuisance animals like dogs, cats and mice were 5.65 more likely to be C. burnetii seropositive compared to dairy cattle without access to these animals. On the other hand, dairy cattle that have no tick infestation are 93% less likely to be seropositive for C. burnetii [OR = 0.07 (95%CI: 0.01-0.74); P = 0.027]. Concerning farm-level data, farms of larger herd sizes were 1.03 more likely to be C. burnetii seropositive than small herd farms [OR = 1.03 (95%CI: 0.99-1.06)]. The result from slaughterhouse indicates that as the age of cattle increase by 1 year their chance of being C. burnetii seropositive increases by 2.27 [OR = 2.27 (95%CI: 1.93-2.68); p = 0.000]., Conclusion: Considering its zoonotic and economic burden the seroprevalence of Q fever recorded in this study is of eminent public health concern with a farm-level and slaughterhouse seroprevalence of 6.17 and 11.79% respectively. Based on modifiable risk factors identified in this study, Q fever management plans better be focused on health education and awareness campaigns for abattoir workers and dairy farm workers. Dairy farm Q fever management plans should contemplate improved dairy herd biosecurity with regards to cattle tick infestation, keeping different livestock species segregated and avoiding mixing of herd with others with unknown health status.

Bovine brucellosis is a serious zoonotic infectious disease with widespread occurrence in developing countries like Ethiopia. A cross-sectional study was conducted from November 2017 to November 2018 to investigate the prevalence and associated risk factors of brucellosis in breeding female cattle under the traditional production system of the Jimma zone in Ethiopia. Blood samples were collected from a total of 423 breeding female cattle to test the presence of Brucella antibody. The presence of antibody against Brucella spp. was serially tested first by the Rose Bengal Plate test, then positive sera were confirmed using the complement fixation test. Potential risk factors for Brucella seropositivity were analyzed using multivariable logistic regression analysis. An overall 11.6% (95%CI: 6.25 - 16.94) and 4.3% (95%CI: 2.15-5.89) seroprevalence of brucellosis was recorded at herd and animal level, respectively in study areas. We identified age (OR=9.6, 95% CI: 2.08-44.07), breed (OR=4.5, 95%CI: 1.54-12.99), herd size (OR=10.4, 95%CI: 1.27-85.04) and species composition (OR=4.4, 95%CI: 1.31-14.89) as risk factors for Brucella infection. Herd level analysis of risk factor shows that herds kept with sheep and/goats was at higher risk (OR=3.7, 95% CI: 1.25-11.17) of acquired Brucella infection. This result showed that brucellosis was a widely spread disease in the study areas. Thus, important to carry out appropriate control methods and creating awareness on public zoonotic transmissions of brucellosis are recommended. Moreover, further investigation should be carried out to isolate and characterized brucellosis as a cause of reproduction problems in the study areas., (© 2020 The Authors.)

Mycobacterium bovis ( M. bovis ) has an exceptionally wide host range including sheep. Information on tuberculosis (TB) in sheep is scarce, and there appears to be conflicting opinions about the relative susceptibility of sheep to infection. In Ethiopia, there was no single previous report on tuberculosis in sheep, though mixed farming of cattle and sheep is a common practice. In this study, following the observation of TB-like lesions on sheep died from sheep flock kept in contact with cattle herd, further investigation was conducted on the flock to assess the magnitude of the infection and identify and characterize the causative M. bovis strain . An outbreak investigation was carried out on 26 eligible sheep out of 33 sheep found on the farm. Comparative intradermal tuberculin (CIDT) test, postmortem examination, Mycobacterium culturing, and spoligotyping were the techniques used in the study. The prevalence of TB in the tested sheep was 15% (4/26). All the sheep that were positive to CIDT had gross lesions suggestive of TB. Three of the positive sheep had extensive and multiple lesions. M. bovis was isolated from all four sheep and the strain was identified as spoligotype SBO134. The in-contact dairy cows were screened for TB and 98% (45/46) of the cows tested positive to CIDT. Furthermore, the same strain, SB0134, was also isolated from the two in-contact cows. The isolation of a matching genotype (SB0134) of M. bovis from both species sharing a known epidemiologic link strongly suggests that the sheep flock might have acquired the pathogen from the dairy cows. This warrants strict physical separation of the sheep flock from the cattle herd to prevent such interspecies transmission of M. bovis .

A cross-sectional study was carried out in Jimma town and Chora Botor district of Jimma zone from February 2014 to May 2014 to determine seroprevalence and risk factors of brucellosis in cattle. A total of 348 blood samples (174 each from zebu and crossbreed) were collected. The sera were separated and screened by Rose Bengal plate test (RBPT), and positive sera were retested by complement fixation test (CFT) for confirmation. The overall seroprevalence of bovine brucellosis was 1.4 and 0.3 % as tested by RBPT and CFT, respectively. The seroprevalence of bovine brucellosis in indigenous and crossbreed cattle was 1.1 and 0.6 % and 1.7 and 0 % using RBPT and CFT, respectively. Retained fetal membrane was the only risk factor found to be significantly associated with seropositivity of brucellosis in this study (p = 0.019). The overall seroprevalence of brucellosis was very low. However, due to the zoonotic and economic importance of the disease, prevention and control measures are required to stop further spread of the disease. To effectively implement this, the One Health (OH) is the most constructive approach we recommend.