Genotyping of methicillin-resistant Staphylococcus aureus (MRSA) isolated from milk and dairy products in South Italy

Abstract

Methicillin-resistant Staphylococcus aureus (MRSA) is a pathogen emerging in hospitals as well as community and livestock. MRSA is a significant and costly public health concern because it may enter the human food chain and contaminate milk and dairy products causing foodborne illness. This study aimed to determine the occurrence and the characteristics of MRSA isolated from 3760 samples of milk and dairy products in a previous survey conducted in southern Italy during 2008-2014. Overall out of 484 S. aureus strains isolated, 40 (8.3%) were MRSA and were characterized by spa-typing, Multi-Locus Sequence Typing, SCCmec typing, Staphylococcal enterotoxins (SEs) genes, Panton-Valentine Leukocidin (PVL) genes and ability to form biofilm. The most frequently recovered STs were ST152 (t355-67.5%), followed by ST398 (t899, t108-25%), ST1 (t127-5%) and ST5 (t688-2.5%). All isolates harboured the SCCmec type V (92.5%) or IVa (25%). In one isolate (2.5%), ST398/t899, the SCCmec resulted not detected. Three isolates (7.5%) carried one or more enterotoxin encoding genes (one strain had seg, sei, sem, sen and seo genes; two strains had seh gene). The 50% of isolated strains harboured PVL-encoding genes. Molecular analysis for icaA and icaD genes showed: 72.5% icaA and icaD positive, 25% only icaD gene and one icaA and icaD negative. The detection of MRSA in food of animal origin is a potential health hazard, thus it is necessary monitoring of food-producing animals and improving hygiene standards in food practices in order to reduce the microbiological risk to minimum.

Investigation of mecA gene, virulence traits and antibiotic resistance profiles in methicillin‐resistant Staphylococcus aureus isolates from dairy products

“…This result is similar to those published by Traversa et al (2015) and Papadopoulos et al (2018). A contrary result was reported by Basanisi et al (2017) who indicated a prevalence of 50% for the pvl gene among MRSA isolates from milk and dairy. In addition, a survey performed in Turkey demonstrated the presence of one pvl-positive MRSA strain originating from cheese (Sudagidan & Aydin, 2010).…”

“…The presence of MRSA in milk was reported by Li, Zhou, Wang, Xue, and Zhao () who found one mecA ‐positive and seven mecA ‐negative but phenotype‐positive MRSA strains in milk samples (Li et al, ). Studies performed during the last decade in different countries indicated the presence of mec A‐positive and/or phenotype‐positive MRSA (Basanisi, La Bella, Nobili, Franconieri, & La Salandra, ; Carfora et al, ; Kamal, Bayoumi, & Abd El Aal, ; Song et al, ; Traversa et al, ) in milk. The occurrence of MRSA in milk was also reported by researches from Turkey (Buyukcangaz et al, ; Pamuk, Yildirim, Seker, Gurler, & Kara, ; Siriken, Yildirim, Güney, Erol, & Durupinar, ).…”

Phenotypic and Molecular Detection of Biofilm Formation in Staphylococcus aureus Isolated from Different Sources in Algeria

“…In the same tendency, the binding and/or insertion ability of S. aureus to mammary gland epithelium was related to the production of biofilms [13]. In addition, biofilm formation limits antimicrobial agents therapy of mastitis by reducing the diffusion of antibiotics through the biofilm matrix [14,63].…”

Methicillin-resistant Staphylococcus aureus in veterinary professionals in 2017 in the Czech Republic

“…MRSA carriage or infections were described mostly in farm animals, such as pigs [19], cattle [20], sheep [21], horses [22] or poultry [23]. Transmission to humans has been documented, mostly after prolonged, repeated and close contact with a colonized animal [24] or through a contaminated vehicle such as meat [25] or dairy products [26]. Several studies confirmed the presence of MRSA ST398 in pigs, goats, cow and sheep and their meat and milk products in the Czech Republic [27][28][29][30].…”