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Zuo W, Yang D, Wu X, Zhang B, Wang X, Hu J, Qi J, Tian M, Bao Y, Wang S. The aroA and luxS Double-Gene Mutant Strain Has Potential to Be a Live Attenuated Vaccine against Salmonella Typhimurium. Vaccines (Basel) 2024; 12:162. [PMID: 38400145 PMCID: PMC10893546 DOI: 10.3390/vaccines12020162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Revised: 01/25/2024] [Accepted: 01/29/2024] [Indexed: 02/25/2024] Open
Abstract
Salmonella Typhimurium (S. Typhimurium) is a zoonotic pathogen posing a threat to animal husbandry and public health. Due to the emergence of antibiotic-resistant strains, alternative prevention and control strategies are needed. Live attenuated vaccines are an ideal option that provide protection against an S. Typhimurium pandemic. To develop a safe and effective vaccine, double-gene mutations are recommended to attenuate virulence. In this study, we chose aroA and luxS genes, whose deletion significantly attenuates S. Typhimurium's virulence and enhances immunogenicity, to construct the double-gene mutant vaccine strain SAT52ΔaroAΔluxS. The results show that the mutant strain's growth rate, adherence and invasion of susceptible cells are comparable to a wild-type strain, but the intracellular survival, virulence and host persistence are significantly attenuated. Immunization assay showed that 106 colony-forming units (CFUs) of SAT52ΔaroAΔluxS conferred 100% protection against wild-type challenges; the bacteria persistence in liver and spleen were significantly reduced, and no obvious pathological lesions were observed. Therefore, the double-gene mutant strain SAT52ΔaroAΔluxS exhibits potential as a live attenuated vaccine candidate against S. Typhimurium infection.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Yanqing Bao
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China; (W.Z.); (D.Y.); (X.W.); (B.Z.); (X.W.); (J.H.); (J.Q.); (M.T.)
| | - Shaohui Wang
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China; (W.Z.); (D.Y.); (X.W.); (B.Z.); (X.W.); (J.H.); (J.Q.); (M.T.)
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Li Z, Wu M, Yan H, Meng Z, Gao B, Dong Q. Antibacterial Effect and Possible Mechanism of Sesamol against Foodborne Pathogens. Foods 2024; 13:435. [PMID: 38338570 PMCID: PMC10855640 DOI: 10.3390/foods13030435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 01/12/2024] [Accepted: 01/26/2024] [Indexed: 02/12/2024] Open
Abstract
Food safety problems caused by foodborne pathogens have become a major public issue, and the search for efficient and safe bacteriostatic agents has gained attention. Sesamol (SE), a phenolic compound abundant in sesame oil, offers numerous health benefits and exhibits certain antibacterial properties. The purpose of this study was to evaluate the antibacterial effect and potential mechanisms of SE against representative foodborne pathogens, including Listeria monocytogenes, Staphylococcus aureus, Bacillus cereus, Escherichia coli, and Salmonella serovar Enteritidis. The results showed that SE significantly inhibited the growth of the five pathogenic bacteria in sterile saline and pasteurized milk by 2.16-4.16 log10 CFU/g within 48 h. The results of the minimum bactericidal concentration and time-kill assay showed that SE had a greater inhibitory effect on L. monocytogenes compared with other bacteria. Additionally, SE was found to alter the cell membranes' permeability in these bacteria, resulting in the release of intercellular proteins and DNA. A scanning electron microscopy analysis showed that exposure to SE resulted in significant changes in bacterial morphology, producing cell shrinkage and deformation. These findings suggest that SE could inhibit both Gram-negative and Gram-positive bacteria by interfering with the function and morphology of bacterial cells.
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Affiliation(s)
| | | | | | | | | | - Qingli Dong
- School of Health Science and Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China; (Z.L.); (M.W.); (H.Y.); (Z.M.); (B.G.)
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Aworh MK, Nilsson P, Egyir B, Owusu FA, Hendriksen RS. Rare serovars of non-typhoidal Salmonella enterica isolated from humans, beef cattle and abattoir environments in Nigeria. PLoS One 2024; 19:e0296971. [PMID: 38252613 PMCID: PMC10802957 DOI: 10.1371/journal.pone.0296971] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Accepted: 12/25/2023] [Indexed: 01/24/2024] Open
Abstract
INTRODUCTION Salmonella is considered one of the most significant pathogens in public health since it is a bacterium that is frequently linked to food-borne illnesses in humans. Some Salmonella serovars are responsible for outbreaks that are connected to the consumption of animal products. Cattle are connected to humans through a shared environment and the food chain as a significant source of animal protein. In Nigeria, antimicrobial medications are easily accessible for use in food-producing animals. Abattoir environments are reservoirs of foodborne bacteria like non-typhoidal Salmonella enterica (NTS), that have become resistant to antibiotics used for prophylaxis or treatment in animals. This study investigated the prevalence and resistance patterns of Salmonella enterica serovars in abattoir employees, beef cattle and abattoir environments in Abuja and Lagos, Nigeria. METHODS A total of 448 samples were collected from healthy personnel, slaughtered cattle, and abattoir environments between May and December 2020. Using Kirby-Bauer disk diffusion method, the resistance profile of NTS isolates were determined. Multidrug resistance (MDR) was considered when NTS was resistant to ≥3 antimicrobial drug classes. We performed phenotypic and genotypic characterizations of all Salmonella isolates including serotyping. Descriptive statistics were used to analyze the data. RESULTS Twenty-seven (6%) NTS isolates were obtained. Prevalence of NTS was highest in abattoir environments (15.5%; 9/58), followed by cattle (4.8%;13/272) and abattoir employees (4.2%; 5/118). A high prevalence of resistance was observed for gentamicin (85.2%; 23/27) and tetracycline (77.8%; 21/27). Whole-genome sequencing of 22 NTS showed dissemination of aac(6')-laa (22/22), qnrB19 (1/22), fosA7 (1/22), and tetA (1/22) genes. Serovar diversity of NTS varied with source. S. Anatum, a rare serovar predominated with a prevalence of 18.2% (4/22). Chromosomal point mutations showed ParC T57S substitution in 22 NTS analyzed. Among 22 NTS, 131 mobile genetic elements (MGEs) were detected including insertion sequences (56.5%) and miniature inverted repeats (43.5%). Two integrating MGEs IS6 and IS21 were observed to carry the tetA gene + Incl-1 on the same contig in NTS originating from cattle. Rare serovars namely S. Abony and S. Stormont with MDR phenotypes recovered from cattle and abattoir environments were closely related with a pairwise distance of ≤5 SNPs. CONCLUSIONS First report of rare serovars in Nigeria with MDR phenotypes in humans, cattle, and abattoir environments. This study demonstrates the spread of resistance in the abattoir environment possibly by MGEs and emphasizes the importance of genomic surveillance. Beef cattle may be a risk to public health because they spread a variety of rare Salmonella serovars. Therefore, encouraging hand hygiene among abattoir employees while processing beef cattle will further reduce NTS colonization in this population. This requires a One Health collaborative effort among various stakeholders in human health, animal health, and environmental health.
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Affiliation(s)
- Mabel Kamweli Aworh
- Department of Population Health and Pathobiology, College of Veterinary Medicine, North Carolina State University, Raleigh, North Carolina, United States of America
- Nigeria Field Epidemiology and Laboratory Training Programme, Abuja, Nigeria
| | - Pernille Nilsson
- Research Group for Global Capacity Building, National Food Institute, WHO Collaborating Centre (WHO CC) for Antimicrobial Resistance in Foodborne Pathogens and Genomics, FAO Reference Laboratory (FAO RL) for Antimicrobial Resistance, European Union Reference Laboratory for Antimicrobial Resistance (EURL-AR), Technical University of Denmark, Kongens Lyngby, Denmark
| | - Beverly Egyir
- Department of Bacteriology, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Accra, Ghana
| | - Felicia Amoa Owusu
- Department of Bacteriology, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Accra, Ghana
| | - Rene S. Hendriksen
- Research Group for Global Capacity Building, National Food Institute, WHO Collaborating Centre (WHO CC) for Antimicrobial Resistance in Foodborne Pathogens and Genomics, FAO Reference Laboratory (FAO RL) for Antimicrobial Resistance, European Union Reference Laboratory for Antimicrobial Resistance (EURL-AR), Technical University of Denmark, Kongens Lyngby, Denmark
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Mlangeni LN, Ramatla T, Lekota KE, Price C, Thekisoe O, Weldon C. Occurrence, Antimicrobial Resistance, and Virulence Profiles of Salmonella Serovars Isolated from Wild Reptiles in South Africa. Int J Microbiol 2024; 2024:5213895. [PMID: 38222969 PMCID: PMC10787053 DOI: 10.1155/2024/5213895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 12/19/2023] [Accepted: 12/29/2023] [Indexed: 01/16/2024] Open
Abstract
Reptiles are carriers of an array of microorganisms, including significant zoonotic bacteria of the genus Salmonella, which cause a disease referred to as salmonellosis that affects both animals and humans. This study investigated the occurrence of Salmonella serovars in wild reptiles at Timbavati Private Game Reserve in Limpopo Province, South Africa, and examined their virulence and antimicrobial resistance gene profiles. A total of 19 wild reptiles were sampled, which resulted in 30 presumptive Salmonella isolates. The isolates were identified using polymerase chain reaction (PCR) by amplifying the invA gene and were further confirmed by 16S rRNA gene sequencing. Salmonella serovars were detected in chameleons (36.8%), lizards (31.6%), snakes (15.8%), and tortoises (15.8%). The use of 16S rRNA gene sequencing revealed that Salmonella enterica subsp. enterica serovar Salamae (30%), S. enterica subsp. enterica (16.7%), S. enterica subsp. enterica serovar Typhimurium (13.3%), and S. enterica subsp. enterica serovar Indiana (13.3%) were the four most common subspecies among the investigated 30 isolates. Detected virulence genes included pagN (100%), hilA (96.7%), ssrB (96.7%), prgH (86.7%), and marT (86.7%). The isolates exhibited resistance to nalidixic acid (43.3%) and kanamycin (43.3%), followed by streptomycin (16.7%) and ciprofloxacin (3.3%). Antibiotic-resistant genes were detected as follows: strA, strB, qnrA, qnrS, parC, aadA, aac(6')-Ib, and aac(6')-Ib-cr at 33.3%, 6.7%, 16.7, 13.3%, 10%, 23.3%, 6.7%, and 10%, respectively. The findings highlight the necessity of educational initiatives aimed at reducing reptile-related infections. Effective antibiotic treatment appears promising for infection, given the minimal drug resistance observed in reptile Salmonella serovars in the current study.
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Affiliation(s)
- Lungile N. Mlangeni
- Unit for Environmental Sciences and Management, North-West University, Potchefstroom 2531, South Africa
| | - Tsepo Ramatla
- Unit for Environmental Sciences and Management, North-West University, Potchefstroom 2531, South Africa
- Gastrointestinal Research Unit, Department of Surgery, School of Clinical Medicine, University of the Free State, Bloemfontein 9300, South Africa
| | - Kgaugelo E. Lekota
- Unit for Environmental Sciences and Management, North-West University, Potchefstroom 2531, South Africa
| | - Cormac Price
- Unit for Environmental Sciences and Management, North-West University, Potchefstroom 2531, South Africa
| | - Oriel Thekisoe
- Unit for Environmental Sciences and Management, North-West University, Potchefstroom 2531, South Africa
| | - Che Weldon
- Unit for Environmental Sciences and Management, North-West University, Potchefstroom 2531, South Africa
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Teklemariam AD, Al-Hindi RR, Albiheyri RS, Alharbi MG, Alghamdi MA, Filimban AAR, Al Mutiri AS, Al-Alyani AM, Alseghayer MS, Almaneea AM, Albar AH, Khormi MA, Bhunia AK. Human Salmonellosis: A Continuous Global Threat in the Farm-to-Fork Food Safety Continuum. Foods 2023; 12:foods12091756. [PMID: 37174295 PMCID: PMC10178548 DOI: 10.3390/foods12091756] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Revised: 04/18/2023] [Accepted: 04/20/2023] [Indexed: 05/15/2023] Open
Abstract
Salmonella is one of the most common zoonotic foodborne pathogens and a worldwide public health threat. Salmonella enterica is the most pathogenic among Salmonella species, comprising over 2500 serovars. It causes typhoid fever and gastroenteritis, and the serovars responsible for the later disease are known as non-typhoidal Salmonella (NTS). Salmonella transmission to humans happens along the farm-to-fork continuum via contaminated animal- and plant-derived foods, including poultry, eggs, fish, pork, beef, vegetables, fruits, nuts, and flour. Several virulence factors have been recognized to play a vital role in attaching, invading, and evading the host defense system. These factors include capsule, adhesion proteins, flagella, plasmids, and type III secretion systems that are encoded on the Salmonella pathogenicity islands. The increased global prevalence of NTS serovars in recent years indicates that the control approaches centered on alleviating the food animals' contamination along the food chain have been unsuccessful. Moreover, the emergence of antibiotic-resistant Salmonella variants suggests a potential food safety crisis. This review summarizes the current state of the knowledge on the nomenclature, microbiological features, virulence factors, and the mechanism of antimicrobial resistance of Salmonella. Furthermore, it provides insights into the pathogenesis and epidemiology of Salmonella infections. The recent outbreaks of salmonellosis reported in different clinical settings and geographical regions, including Africa, the Middle East and North Africa, Latin America, Europe, and the USA in the farm-to-fork continuum, are also highlighted.
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Affiliation(s)
- Addisu D Teklemariam
- Department of Biological Sciences, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Rashad R Al-Hindi
- Department of Biological Sciences, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Raed S Albiheyri
- Department of Biological Sciences, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
- Centre of Excellence in Bionanoscience Research, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Mona G Alharbi
- Department of Biological Sciences, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Mashail A Alghamdi
- Department of Biological Sciences, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Amani A R Filimban
- Department of Biological Sciences, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Abdullah S Al Mutiri
- Laboratory Department, Saudi Food and Drug Authority, Riyadh 12843, Saudi Arabia
| | - Abdullah M Al-Alyani
- Laboratory Department, Saudi Food and Drug Authority, Jeddah 22311, Saudi Arabia
| | - Mazen S Alseghayer
- Department of Biological Sciences, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
- Monitoring and Risk Assessment Department, Saudi Food and Drug Authority, Riyadh 13513, Saudi Arabia
| | - Abdulaziz M Almaneea
- Department of Biological Sciences, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
- Monitoring and Risk Assessment Department, Saudi Food and Drug Authority, Riyadh 13513, Saudi Arabia
| | - Abdulgader H Albar
- Department of Biological Sciences, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
- Department of Microbiology and Medical Parasitology, Faculty of Medicine, Jeddah University, Jeddah 23218, Saudi Arabia
| | - Mohsen A Khormi
- Department of Biological Sciences, Faculty of Sciences, Jazan University, Jazan 82817, Saudi Arabia
| | - Arun K Bhunia
- Molecular Food Microbiology Laboratory, Department of Food Science, Purdue University, West Lafayette, IN 47907, USA
- Purdue Institute of Inflammation, Immunology, and Infectious Disease, Purdue University, West Lafayette, IN 47907, USA
- Purdue University Interdisciplinary Life Science Program (PULSe), West Lafayette, IN 47907, USA
- Department of Comparative Pathobiology, Purdue University, West Lafayette, IN 47907, USA
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Oludairo OO, Kwaga JKP, Kabir J, Abdu PA, Gitanjali A, Perrets A, Cibin V, Lettini AA, Aiyedun JO. Ecology and epidemiology of Salmonella spp. isolated from the environment and the roles played by wild animals in their maintenance. INTERNATIONAL JOURNAL OF ONE HEALTH 2023. [DOI: 10.14202/ijoh.2023.1-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023] Open
Abstract
Salmonella is a ubiquitous organism of public health importance that causes diarrhea and other systemic disease syndromes. The ecology and epidemiology of the organism in addition to the roles played by wild animals are important in understanding its disease. Relevant published peer-reviewed literature was obtained after imputing the study's keywords into the Google search engine. The publications were thereafter saved for the study. The study revealed the ecology of Salmonella is directly related to its epidemiology. These were found to be either positively or negatively influenced by the living and non-living parts of the environment. Free-ranging and captive wild animals can serve as asymptomatic carriers of Salmonella, therefore, help to maintain the cycle of the disease since wildlife serves as reservoir hosts to over 70% of emerging zoonotic diseases. Cockroaches transmit Salmonella through their feces, and body parts and when ingested by birds and animals. The statistically significant over 83% of Salmonella isolation in lizards suggests the reptile could be a source of Salmonella distribution. Snakes, foxes, badgers, rodents, and raccoons have been reported to have Salmonella as a natural component of their gut with the ability to shed the organism often. The high occurrence (>45%) of diverse Salmonella serovars coupled with the fact that some of these animals were handled, kept as pets and consumed by man portends these animals as potential sources of transmission of the organism and the disease. The etiology and epidemiology of Salmonella are overtly affected by several environmental factors which also determine their survival and maintenance. The roles played by wild animals in the relationship, transmission, growth or interaction within and between Salmonella spp., the occurrence, prevalence, and distribution of the organism help maintain the organism in the environment. An understanding of the roles played by the different parts of the environment and wild animals in the ecology and epidemiology of Salmonella can help make informed decisions on the prevention and control of the diseases it causes. This review aimed to investigate the relationship between ecology, epidemiology, and environment, including the roles played by wild animals in the maintenance of the organism and its disease.
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Affiliation(s)
- Oladapo Oyedeji Oludairo
- Department of Veterinary Public Health and Preventive Medicine, University of Ilorin, Ilorin, Nigeria
| | - Jacob K. P. Kwaga
- Department of Veterinary Public Health and Preventive Medicine, Ahmadu Bello University, Zaria, Nigeria
| | - Junaid Kabir
- Department of Veterinary Public Health and Preventive Medicine, Ahmadu Bello University, Zaria, Nigeria
| | - Paul A. Abdu
- Department of Veterinary Medicine, Ahmadu Bello University, Zaria, Nigeria
| | - Arya Gitanjali
- OIE Salmonella Reference Laboratory, National Microbiology Laboratory, Public Health Agency of Canada, Guelph, Ontario, Canada
| | - Ann Perrets
- OIE Salmonella Reference Laboratory, National Microbiology Laboratory, Public Health Agency of Canada, Guelph, Ontario, Canada
| | - Veronica Cibin
- Salmonella Reference Laboratory, Istituto Zooprofilattico Sperimentale delle Venezie Viale dell'Università, Legnaro (PD), Italy
| | - Antonia Anna Lettini
- Salmonella Reference Laboratory, Istituto Zooprofilattico Sperimentale delle Venezie Viale dell'Università, Legnaro (PD), Italy
| | - Julius O. Aiyedun
- Department of Veterinary Public Health and Preventive Medicine, University of Ilorin, Ilorin, Nigeria
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Ramatla T, Tawana M, Mphuthi MBN, Onyiche TE, Lekota KE, Monyama MC, Ndou R, Bezuidenhout C, Thekisoe O. Prevalence and antimicrobial resistance profiles of Campylobacter species in South Africa: a "One Health" approach using systematic review and meta-analysis. Int J Infect Dis 2022; 125:294-304. [PMID: 36336247 DOI: 10.1016/j.ijid.2022.10.042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 10/28/2022] [Accepted: 10/29/2022] [Indexed: 11/06/2022] Open
Abstract
OBJECTIVES This study investigated the prevalence and antibiotic resistance (AR) profiles of Campylobacter spp. isolated from animals, humans, and the environment in South Africa based on available published data. METHODS Original articles published from January 1, 1990 to January 1, 2021 were searched from PubMed, ScienceDirect, Google Scholar, Africa Index Medicus, Scopus, and African Journal Online databases. Data were analyzed with Comprehensive Meta-Analysis (version 3.0). RESULTS After screening, articles on animals (n = 25), humans (n = 7), environment (n = 3), animals/environment (n = 2), and a (n = 1) study on animals, humans, and the environment were included in this review. The pooled prevalence estimates (PPEs) were 28.8%, 16.4%, and 28.4% in animals, humans, and the environment, respectively. The Campylobacter jejuni and Campylobacter coli species were commonly isolated from humans, animals, and the environment in South Africa. The AR profiles were screened from 2032 Campylobacter spp., with the highest PPE of AR observed against clindamycin (76.9%) and clarithromycin (76.5%). Campylobacter isolates tested with the disk diffusion assay and minimum inhibitory concentration methods recorded an overall AR prevalence of 35.3% and 37.1%, respectively, whereas multidrug resistance PPE was 35.3%. CONCLUSION Regular surveillance of Campylobacter spp. prevalence and its antimicrobial resistance strains is recommended, as well as the formulation of a "One Health" approach for better management and control of Campylobacter spp. infection in South Africa.
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Affiliation(s)
- Tsepo Ramatla
- Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South Africa
| | - Mpho Tawana
- Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South Africa
| | - Malekoba B N Mphuthi
- Department of Animal Health, School of Agriculture, North-West University, Mmabatho, South Africa
| | - ThankGod E Onyiche
- Department of Veterinary Parasitology and Entomology, University of Maiduguri, Maiduguri, Nigeria
| | - Kgaugelo E Lekota
- Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South Africa
| | - Maropeng C Monyama
- Department of Life and Consumer Sciences, University of South Africa, Florida, South Africa
| | - Rendani Ndou
- Department of Animal Health, School of Agriculture, North-West University, Mmabatho, South Africa
| | - Carlos Bezuidenhout
- Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South Africa
| | - Oriel Thekisoe
- Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South Africa
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