Occurrence, antimicrobial susceptibility, and resistance genes of Staphylococcus aureus in milk and milk products in the Arsi highlands of Ethiopia
Abstract Background In Ethiopia, milk production and handling practices often lack proper hygiene measures, leading to the potential contamination of milk and milk products with Staphylococcus aureus (S. aureus), including methicillin-resistant strains, posing significant public health concerns. Thi...
| Main Authors: | , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
BMC
2024-04-01
|
| Series: | BMC Microbiology |
| Subjects: | |
| Online Access: | https://doi.org/10.1186/s12866-024-03288-3 |
| _version_ | 1797199638667722752 |
|---|---|
| author | Abiot Deddefo Gezahegne Mamo Minda Asfaw Adem Edao Adem Hiko Dereje Fufa Mohammed Jafer Melaku Sombo Kebede Amenu |
| author_facet | Abiot Deddefo Gezahegne Mamo Minda Asfaw Adem Edao Adem Hiko Dereje Fufa Mohammed Jafer Melaku Sombo Kebede Amenu |
| author_sort | Abiot Deddefo |
| collection | DOAJ |
| description | Abstract Background In Ethiopia, milk production and handling practices often lack proper hygiene measures, leading to the potential contamination of milk and milk products with Staphylococcus aureus (S. aureus), including methicillin-resistant strains, posing significant public health concerns. This study aimed to investigate the occurrence, antimicrobial susceptibility profiles and presence of resistance genes in S. aureus strains isolated from milk and milk products. Methods A cross-sectional study was conducted in the Arsi highlands, Oromia, Ethiopia from March 2022 to February 2023. A total of 503 milk and milk product samples were collected, comprising 259 raw milk, 219 cottage cheese, and 25 traditional yogurt samples. S. aureus isolation and coagulase-positive staphylococci enumeration were performed using Baird-Parker agar supplemented with tellurite and egg yolk. S. aureus was further characterized based on colony morphology, Gram stain, mannitol fermentation, catalase test, and coagulase test. Phenotypic antimicrobial resistance was assessed using the Kirby–Bauer disc diffusion method, while the polymerase chain reaction (PCR) was employed for confirming the presence of S. aureus and detecting antimicrobial resistance genes. Results S. aureus was detected in 24.9% of the milk and milk products, with the highest occurrence in raw milk (40.9%), followed by yogurt (20%), and cottage cheese (6.4%). The geometric mean for coagulase-positive staphylococci counts in raw milk, yogurt, and cottage cheese was 4.6, 3.8, and 3.2 log10 CFU/mL, respectively. Antimicrobial resistance analysis revealed high levels of resistance to ampicillin (89.7%) and penicillin G (87.2%), with 71.8% of the isolates demonstrating multidrug resistance. Of the 16 S. aureus isolates analyzed using PCR, all were found to carry the nuc gene, with the mecA and blaZ genes detected in 50% of these isolates each. Conclusion This study revealed the widespread distribution of S. aureus in milk and milk products in the Arsi highlands of Ethiopia. The isolates displayed high resistance to ampicillin and penicillin, with a concerning level of multidrug resistance. The detection of the mecA and blaZ genes in selected isolates is of particular concern, highlighting a potential public health hazard and posing a challenge to effective antimicrobial treatment. These findings highlight the urgent need to enhance hygiene standards in milk and milk product handling and promote the rational use of antimicrobial drugs. Provision of adequate training for all individuals involved in the dairy sector can help minimize contamination. These measures are crucial in addressing the threats posed by S. aureus, including methicillin-resistant strains, and ensuring the safety of milk and its products for consumers. |
| first_indexed | 2024-04-24T07:18:56Z |
| format | Article |
| id | doaj.art-de5cd45b6b9b49dea393ad74c4a45089 |
| institution | Directory Open Access Journal |
| issn | 1471-2180 |
| language | English |
| last_indexed | 2024-04-24T07:18:56Z |
| publishDate | 2024-04-01 |
| publisher | BMC |
| record_format | Article |
| series | BMC Microbiology |
| spelling | doaj.art-de5cd45b6b9b49dea393ad74c4a450892024-04-21T11:10:42ZengBMCBMC Microbiology1471-21802024-04-0124111410.1186/s12866-024-03288-3Occurrence, antimicrobial susceptibility, and resistance genes of Staphylococcus aureus in milk and milk products in the Arsi highlands of EthiopiaAbiot Deddefo0Gezahegne Mamo1Minda Asfaw2Adem Edao3Adem Hiko4Dereje Fufa5Mohammed Jafer6Melaku Sombo7Kebede Amenu8College of Agriculture and Environmental Sciences, Arsi UniversityCollege of Veterinary Medicine and Agriculture, Addis Ababa UniversityCollege of Agriculture and Environmental Sciences, Arsi UniversityCollege of Veterinary Medicine, Haramaya UniversityCollege of Veterinary Medicine, Haramaya UniversityAsella Regional Veterinary LaboratoryCollege of Veterinary Medicine, Haramaya UniversityNational Animal Health InstituteCollege of Veterinary Medicine and Agriculture, Addis Ababa UniversityAbstract Background In Ethiopia, milk production and handling practices often lack proper hygiene measures, leading to the potential contamination of milk and milk products with Staphylococcus aureus (S. aureus), including methicillin-resistant strains, posing significant public health concerns. This study aimed to investigate the occurrence, antimicrobial susceptibility profiles and presence of resistance genes in S. aureus strains isolated from milk and milk products. Methods A cross-sectional study was conducted in the Arsi highlands, Oromia, Ethiopia from March 2022 to February 2023. A total of 503 milk and milk product samples were collected, comprising 259 raw milk, 219 cottage cheese, and 25 traditional yogurt samples. S. aureus isolation and coagulase-positive staphylococci enumeration were performed using Baird-Parker agar supplemented with tellurite and egg yolk. S. aureus was further characterized based on colony morphology, Gram stain, mannitol fermentation, catalase test, and coagulase test. Phenotypic antimicrobial resistance was assessed using the Kirby–Bauer disc diffusion method, while the polymerase chain reaction (PCR) was employed for confirming the presence of S. aureus and detecting antimicrobial resistance genes. Results S. aureus was detected in 24.9% of the milk and milk products, with the highest occurrence in raw milk (40.9%), followed by yogurt (20%), and cottage cheese (6.4%). The geometric mean for coagulase-positive staphylococci counts in raw milk, yogurt, and cottage cheese was 4.6, 3.8, and 3.2 log10 CFU/mL, respectively. Antimicrobial resistance analysis revealed high levels of resistance to ampicillin (89.7%) and penicillin G (87.2%), with 71.8% of the isolates demonstrating multidrug resistance. Of the 16 S. aureus isolates analyzed using PCR, all were found to carry the nuc gene, with the mecA and blaZ genes detected in 50% of these isolates each. Conclusion This study revealed the widespread distribution of S. aureus in milk and milk products in the Arsi highlands of Ethiopia. The isolates displayed high resistance to ampicillin and penicillin, with a concerning level of multidrug resistance. The detection of the mecA and blaZ genes in selected isolates is of particular concern, highlighting a potential public health hazard and posing a challenge to effective antimicrobial treatment. These findings highlight the urgent need to enhance hygiene standards in milk and milk product handling and promote the rational use of antimicrobial drugs. Provision of adequate training for all individuals involved in the dairy sector can help minimize contamination. These measures are crucial in addressing the threats posed by S. aureus, including methicillin-resistant strains, and ensuring the safety of milk and its products for consumers.https://doi.org/10.1186/s12866-024-03288-3Antimicrobial resistanceCottage cheeseMilkmecA and blaZ genesStaphylococcus aureusYogurt |
| spellingShingle | Abiot Deddefo Gezahegne Mamo Minda Asfaw Adem Edao Adem Hiko Dereje Fufa Mohammed Jafer Melaku Sombo Kebede Amenu Occurrence, antimicrobial susceptibility, and resistance genes of Staphylococcus aureus in milk and milk products in the Arsi highlands of Ethiopia BMC Microbiology Antimicrobial resistance Cottage cheese Milk mecA and blaZ genes Staphylococcus aureus Yogurt |
| title | Occurrence, antimicrobial susceptibility, and resistance genes of Staphylococcus aureus in milk and milk products in the Arsi highlands of Ethiopia |
| title_full | Occurrence, antimicrobial susceptibility, and resistance genes of Staphylococcus aureus in milk and milk products in the Arsi highlands of Ethiopia |
| title_fullStr | Occurrence, antimicrobial susceptibility, and resistance genes of Staphylococcus aureus in milk and milk products in the Arsi highlands of Ethiopia |
| title_full_unstemmed | Occurrence, antimicrobial susceptibility, and resistance genes of Staphylococcus aureus in milk and milk products in the Arsi highlands of Ethiopia |
| title_short | Occurrence, antimicrobial susceptibility, and resistance genes of Staphylococcus aureus in milk and milk products in the Arsi highlands of Ethiopia |
| title_sort | occurrence antimicrobial susceptibility and resistance genes of staphylococcus aureus in milk and milk products in the arsi highlands of ethiopia |
| topic | Antimicrobial resistance Cottage cheese Milk mecA and blaZ genes Staphylococcus aureus Yogurt |
| url | https://doi.org/10.1186/s12866-024-03288-3 |
| work_keys_str_mv | AT abiotdeddefo occurrenceantimicrobialsusceptibilityandresistancegenesofstaphylococcusaureusinmilkandmilkproductsinthearsihighlandsofethiopia AT gezahegnemamo occurrenceantimicrobialsusceptibilityandresistancegenesofstaphylococcusaureusinmilkandmilkproductsinthearsihighlandsofethiopia AT mindaasfaw occurrenceantimicrobialsusceptibilityandresistancegenesofstaphylococcusaureusinmilkandmilkproductsinthearsihighlandsofethiopia AT ademedao occurrenceantimicrobialsusceptibilityandresistancegenesofstaphylococcusaureusinmilkandmilkproductsinthearsihighlandsofethiopia AT ademhiko occurrenceantimicrobialsusceptibilityandresistancegenesofstaphylococcusaureusinmilkandmilkproductsinthearsihighlandsofethiopia AT derejefufa occurrenceantimicrobialsusceptibilityandresistancegenesofstaphylococcusaureusinmilkandmilkproductsinthearsihighlandsofethiopia AT mohammedjafer occurrenceantimicrobialsusceptibilityandresistancegenesofstaphylococcusaureusinmilkandmilkproductsinthearsihighlandsofethiopia AT melakusombo occurrenceantimicrobialsusceptibilityandresistancegenesofstaphylococcusaureusinmilkandmilkproductsinthearsihighlandsofethiopia AT kebedeamenu occurrenceantimicrobialsusceptibilityandresistancegenesofstaphylococcusaureusinmilkandmilkproductsinthearsihighlandsofethiopia |