Original Scientific Article
Prevalence of the enterotoxigenic Staphylococcus aureus strains isolated from raw milk and cheese produced in North Macedonia
Staphylococcus aureus is an important foodborne pathogen due to toxin-related virulence, invasiveness and antibiotic resistance. The ability of S. aureus strains to produce one or more staphylococcal enterotoxins (SEs) in food has been associated with the occurrence of staphylococcal food poisoning (SFP), which is the most common foodborne intoxication worldwide. The study aimed to determine the count of S. aureus strains in samples of raw cow’s milk and various cheeses produced in R. North Macedonia and to detect their ability to produce enterotoxins by passive agglutination SET RPLA (OXOID, UK) and by enzyme-linked fluorescence assay (ELFA) VIDAS SET 2 (Biomerieux, France). A total of 130 S. aureus strains were analyzed. The ability to produce SEs was determined in 17 (13.1%) strains using the SET RPLA detection kit and in 20 (15.4%) strains using the VIDAS SET 2. The study detected enterotoxigenic strains in cheese samples, despite the low count of S. aureus which was below the detection limit according to the Book of rules for microbiological criteria (Off. G. of R.M no 100/2013). Based on these and similar findings, S. aureus must be considered as a possible cause of intoxication, despite the undetected and underreported cases of SFP in the scientific literature.
Keywords: Staphylococcus aureus, cheese, milk, enterotoxins, SET RPLA, VIDAS SET 2, North Macedonia
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Copyright: © 2021 Ratkova Manovska M. This is an open-access article published under the terms of the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Conflict of Interest Statement
The authors have declared that no competing interests exist.
Macedonian Veterinary Review. Volume 44, Issue 1, Pages 71-77, e-ISSN 1857-7415, p-ISSN 1409-7621, DOI: 10.2478/macvetrev-2021-0014, 2021