Food-borne microorganisms are major pathogens affecting food safety and cause human illness worldwide as a result of consumption of foodstuff, mainly animal products contaminated with vegetative pathogens or their toxins. Most of these microbes have zoonotic importance resulting in significant impact on both public health and economic sectors. Bacteria are the causative agents of two-thirds of human food-borne diseases worldwide with high burden in developing countries. Hence, the objectives of this review paper are to highlight the background of food-borne bacterial pathogens and to review common major food-borne zoonotic bacterial pathogens. Food animals are the major reservoirs of many food-borne zoonotic bacterial pathogens, and food products of animal origin are the main vehicles of transmission. Meat, dairy products, and eggs are the main ways by which people are exposed to zoonotic bacteria. S. aureus, Salmonella species, Campylobacter species, L. monocytogenes, and E. coli are the major zoonotic bacterial pathogens which are the causative agents of food-borne illness and death in the world associated with consumption of contaminated animal products. Production of toxins and structural virulent factors are responsible for the pathogenesis of these bacteria. These major zoonotic bacteria cause human infections which are characterized mainly by gastrointestinal symptoms including nausea, vomiting, diarrhea, abdominal cramps, and other agent-specific symptoms. Some bacteria may cause severe complications. Conventional (culturing), serological, and molecular techniques are important for detection of these common zoonotic bacteria and their toxins in food. Good hygiene, GMP, sanitation in operating procedures, and implementation of standardized HACCP and pasteurization procedures are effective methods for the control and prevention. Currently, the emergence of multidrug-resistant zoonotic bacteria associated with consumption of contaminated animal products is a great concern for the public health, and there should be coordinated surveillance and monitoring system for food-borne zoonotic bacterial pathogens particularly in developing countries including Ethiopia.

No abstract

Bovine brucellosis is an infectious bacterial disease caused by members of genus Brucella, affecting both animals and humans, and resulting in a serious economic loss in animal production sector and deterioration of public health. A cross-sectional study was conducted from November 2014 to April 2015 to determine the seroprevalence and associated risk factors of bovine brucellosis in Sendafa, Oromia Special Zone, Ethiopia. A total of 503 blood samples were collected using a simple random sampling technique from dairy cattle of above 6 months of age with no history of previous vaccination against brucellosis. All sera samples were subjected to both Rose Bengal Plate Test for screening and Complement Fixation Test for confirmation. Accordingly, the overall seroprevalence of bovine brucellosis in the study area was 0.40%. The result showed that the seroprevalence of bovine brucellosis in the study area was not statistically significant with all proposed risk factors. No reactors were observed in male animals. The seroprevalence was observed in animals without previous history of abortion. Moreover, information was gathered on individual animal and farm-level risk factors and other farm characteristics using a questionnaire. Awareness among society was poor, so the positive animals can be a potential hazard to animals and humans in the study area. Therefore, public education should be done to improve the awareness of the community on bovine brucellosis and its public health impact with due consideration on the safe consumption of food of animal origin.

Bovine brucellosis is an infectious bacterial disease caused by members of genus Brucella, affecting both animals and humans, and resulting in a serious economic loss in animal production sector and deterioration of public health. This cross-sectional study was conducted from November 2014 to April 2015 to determine the sero-prevalence and associated risk factors of bovine brucellosis in Sendafa, Oromia special Zone, Ethiopia. A total of 503 blood samples were collected using simple random sampling technique from dairy cattle of above 6 months of age with no history of previous vaccination against brucellosis. All sera samples were demonstrated using both Rose Bengal Plate Test for screening and Compliment Fixation Test for confirmation. Accordingly, the overall sero-prevalence of bovine brucellosis in this area was 0.40%. The result showed that the sero-prevalence of bovine brucellosis in the study area was not statistically significant with all proposed risk factors. Thus, the study revealed the absence of significant statistical variation in the sero-prevalence of bovine brucellosis in different age, sex groups, breeding method and history of previous abortions (P>0.05). No reactors were observed in male animals. Sero-prevalence of 0.40% was observed in animals without previous history of abortion. Moreover, information was gathered on individual animal and farm-level risk factors and other farm characteristics using a questionnaire. The awareness among the society was poor, so the positive animals can be a potential hazard to animals and humans in the study area. Therefore, public education should be done in order to improve the awareness of people on bovine brucellosis and its public health impact with due consideration on the safely consumption of food of animal origin.

E. coli are frequently isolated food-borne pathogens from meat, milk, and their products. Moreover, there has been a significant rise in the antimicrobial resistance patterns of E. coli O157:H7 to commonly used antibiotics. A cross-sectional study was conducted from October 2019 to July 2021 to estimate prevalence and identify associated factors of E. coli and E. coli O157:H7 and to determine antibiotic resistance pattern of E. coli O157:H7 from foods of bovine origin in Dessie and Kombolcha towns. A total of 384 samples were collected. Systematic and simple random sampling techniques were employed for sampling carcasses and milking cows, respectively. E. coli and E. coli O157:H7 were detected according to recommended bacteriological protocols. E. coli O157:H7 strains were evaluated for in vitro antimicrobial susceptibility using agar disk diffusion method. Both descriptive and inferential statistical techniques were applied to analyze the data. Overall prevalence rates of E. coli and E. coli O157:H7 were 54.7% and 6.5%, respectively. Highest prevalence rates of E. coli (79.6%) and E. coli O157:H7 (16.7%) were obtained from carcass swabs and milk tank samples, respectively. Unlike E. coli O157:H7, a statistically significant difference in the E. coli prevalence (P<0.05) was observed among the different sample types. Multidrug resistance was observed among all isolates of E. coli O157:H7. All E. coli O157:H7 isolates (100.0%) were susceptible to Ampicillin, Sulfamethoxazole-trimethoprim, and Norfloxacin. On the contrary, all of the isolates (100%) were resistant to Penicillin G, Vancomycin, and Oxacillin. The current study indicated that different foods of bovine origin in the study area were unsafe for human consumption. Hence, good hygienic production methods should be employed to ensure the safety of foods of bovine origin.

E. coli are frequently isolated food-borne pathogens from meat, milk, and their products. Moreover, there has been a significant rise in the antimicrobial resistance patterns of E. coli O157:H7 to commonly used antibiotics. A cross-sectional study was conducted from October, 2019 to July, 2021 to estimate prevalence and identify associated factors of E. coli and E. coli O157:H7 and to determine antibiotic resistance pattern of E. coli O157:H7 from foods of bovine origin in Dessie and Kombolcha towns. A total of 384 samples were collected. Systematic and simple random sampling techniques were employed for sampling carcasses and milking cows, respectively. E. coli and E. coli O157:H7 were detected according to recommended bacteriological protocols. E. coli O157:H7 strains were evaluated for in vitro antimicrobial susceptibility using agar disk diffusion method. Both descriptive and inferential statistical techniques were applied to analyze the data. Overall prevalence rates of E. coli and E. coli O157:H7 were 54.7% and 6.5%, respectively. Highest prevalence rates of E. coli (79.6%) and E. coli O157:H7 (16.7%) were obtained from carcass swab and milk tank samples, respectively. Unlike E. coli O157:H7, a statistically significant difference in the E. coli prevalence (P<0.05) was observed among the different sample types. Multidrug resistance was observed among all isolates of E. coli O157:H7. All E. coli O157:H7 isolates (100.0%) were susceptible to Ampicillin, Sulfamethoxazole-trimethoprim, and Norfloxacin. On the contrary, all of the isolates (100%) were resistant to Penicillin G, Vancomycin, and Oxacillin. The current study indicated that different foods of bovine origin in the study area were unsafe for human consumption. Hence, good hygienic production methods should be employed to ensure the safety of foods of bovine origin.