The prevalence of Staphylococcus aureus and methicillin resistant Staphylococcus aureus in milk and dairy products in Riyadh, Saudi Arabia

Saudi J Biol Sci. 2021 Dec;28(12):7098-7104. doi: 10.1016/j.sjbs.2021.08.004. Epub 2021 Aug 9.

Abstract

In terms of life- menaced contagion, methicillin resistant Staphylococcus aureus (MRSA) is known to be one of which and it is truly notable in the contaminated food causing a community health anxiety. However, the occurrence of S. aureus and MRSA in diverse kinds of dairy products have been tested in this study. Samples from: raw milk (unpasteurized) from horse, goat, camel, and cow origins and unpacked cheese were checked for the recovered strains of such bacterium and MRSA. Wholly, MRSA isolates were verified for antimicrobial susceptibility and further characterized by mecA and staphylococcal cassette chromosome mec (SCCmec) typing. Also, Panton-Valentine Leukocidin (PVL), Staphylococcus aureus protein A (spa), and Staphylococcal enterotoxins (SEs) were also tested between all positive MRSA isolates in order to discover the virulence factors. Consequently, 70% of the 100 collected dairy products samples were contaminated by S. aureus bacteria and 72.9% of them were defined as MRSA. 9.8% of MRSA isolates contained mecA genes with SCCmec type II (80%) as the most common SCCmec type. Moreover, large number of MRSA isolates were identified as multidrug resistance and 28.6% of MRSA-mecA positive isolates were also carried vancomycin resistance genes (i.e., vanB). Too, spa gene was detected between 9.8% of MRSA isolates but PVL gene was not spotted at all. Additionally, the existing of SEs was variable between MRSA isolates and the most common type was SEH (51%). In general, our results confirmed that raw milk and unpacked cheese in the Kingdom of Saudi Arabia (Riyadh) is a potential vehicle for multidrug resistant MRSA transmission. It is a critical civic health menace and stresses, thus; the need of applying well cleanliness practices is essential.

Keywords: MRSA.