Antibiogram and phylogenetic diversity of enterotoxigenic Staphylococcus aureus strains from milk products and public health implications

Eman E Abdeen; Walid S Mousa; Sarah Y Abdel Salam; Khalid S Al-Maary; Ayman S Mubarak; Ihab M Moussa; Hassan A Hemeg; Abdulaziz M Almuzaini; Ahmed I Alajaji; Roua Abdullah Alsubki; Ayman Elbehiry

doi:10.1016/j.sjbs.2020.06.028

Antibiogram and phylogenetic diversity of enterotoxigenic Staphylococcus aureus strains from milk products and public health implications

Saudi J Biol Sci. 2020 Aug;27(8):1968-1974. doi: 10.1016/j.sjbs.2020.06.028. Epub 2020 Jun 24.

Authors

Affiliations

¹ Department of Bacteriology, Mycology and Immunology, Faculty of Veterinary Medicine, University of Sadat City, 32897, Egypt.
² Department of Animal Medicine and Infectious Diseases, Faculty of Veterinary Medicine, University of Sadat City, 32897, Egypt.
³ Veterinarian at Veterinary Administrator in Khanka, Division of Public Health, Qalyubia Governorate, Egypt.
⁴ Department of Botany and Microbiology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia.
⁵ Department of Microbiology, Faculty of Veterinary Medicine, Cairo University, Giza 11221, Egypt.
⁶ Department of Medical Technology/Microbiology, College of Applied Medical Science, Taibah University, Madinah, Saudi Arabia.
⁷ Department of Veterinary Medicine, College of Agriculture and Veterinary Medicine, Qassim University, Buraydah, Saudi Arabia.
⁸ Department of Clinical Laboratory Science, Chair of Medical and Molecular Genetics Research, College of Applied Medical Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia.
⁹ Department of Public Health, College of Public Health and Health Informatics, Qassim University, Al Bukairiyah, Saudi Arabia.

Abstract

Food poisoning caused by Staphylococcus aureus (S. aureus) toxins is considered one of the foremost public health threat that usually occurs through the ingestion of raw milk contaminated with staphylococcal enterotoxins. The current study spotlights on the prevalence, antibiogram and genetic diversity of S. aureus enterotoxin genes. One hundred and fifty of raw milk (90) and ice cream (60) samples were randomly collected from local markets from Sadat city, Egypt. S. aureus was recovered from 44% of raw milk and 20% of ice cream samples. The identification for the obtained S. aureus isolates was confirmed through targeting the nuc gene. Antibiogram pattern of 32 S. aureus isolates showed high resistance to Cefoxitin, Sulpha/Trimethoprim, Tetracycline, Norfloxacin, Penicillin and Cephradine. However, high susceptibility to Gentamycin and Vancomycin were observed. Multiplex PCR was a competent practise for the recognition of Staphylococcus enterotoxin (SE) genes (SEA, SEB and SED). The phylogenetic analysis of the SED gene of enterotoxigenic S. aureus strains showed identical similarity with 100% to each other and high similarity with other international isolates in GenBank from different localities and sources. The frequency of enterotoxigenic S. aureus strains in milk products could have serious hazardous effects on humans. These results suggested possible strains transmission between different geographical areas through the food and milk product trades.

Keywords: Enterotoxin genes; Milk; S. aureus; Sequencing analysis.