Related Experiment Video

Updated: Apr 11, 2026

Multiplex PCR Assay for Typing of Staphylococcal Cassette Chromosome Mec Types I to V in Methicillin-resistant Staphylococcus aureus
09:03

Multiplex PCR Assay for Typing of Staphylococcal Cassette Chromosome Mec Types I to V in Methicillin-resistant Staphylococcus aureus

Published on: September 5, 2013

12.4K

Methicillin-Resistant Staphylococcus aureus in Raw Milk: Prevalence, SCCmec Typing, Enterotoxin Characterization, and

Alessandra Riva1, Elisa Borghi2, Daniela Cirasola1

  • 1Department of Health Sciences, Università degli Studi di Milano, Via di Rudinì 8, 20142 Milan, Italy.

Journal of Food Protection
|June 4, 2015
PubMed

Insights

This study found toxin-producing and methicillin-resistant Staphylococcus aureus (MRSA) in raw milk from Milan, Italy. These findings highlight the risk of staphylococcal infections spreading from dairy farms.

Area of Science:

  • Food Microbiology
  • Antimicrobial Resistance
  • Public Health

Background:

  • Staphylococcus aureus is a significant cause of foodborne illness.
  • Raw milk and dairy products are common sources of enterotoxigenic and antimicrobial-resistant S. aureus.

Purpose of the Study:

  • To investigate the prevalence of enterotoxigenic and antimicrobial-resistant S. aureus, including MRSA, in raw milk from Milan, Italy.
  • To characterize the antimicrobial susceptibility and toxin gene profiles of isolated S. aureus strains.

Main Methods:

  • Isolation and characterization of S. aureus from 383 raw milk samples.
  • Antimicrobial susceptibility testing and detection of staphylococcal enterotoxin genes (sea-see).
  • Identification of methicillin-resistant S. aureus (MRSA) and SCCmec typing.

Main Results:

  • 45.7% of S. aureus isolates were enterotoxigenic, and 37.1% were resistant to at least one antimicrobial.
  • Seven isolates (20%) were identified as MRSA, with SCCmec types associated with both community and healthcare settings.
  • The Panton-Valentine leukocidin gene was not detected in MRSA strains.

Conclusions:

  • Toxin-producing S. aureus and MRSA strains are present in raw milk in the Milan region.
  • The presence of these strains in dairy farms poses a risk for the dissemination of staphylococcal infections.
  • Further research is needed to develop strategies for monitoring and controlling S. aureus, particularly MRSA, in dairy products.

More Related Videos

Genotyping of Staphylococcus aureus by Ribosomal Spacer PCR RS-PCR08:51

Genotyping of Staphylococcus aureus by Ribosomal Spacer PCR RS-PCR

Published on: November 4, 2016

10.3K
Biosensor for Detection of Antibiotic Resistant Staphylococcus Bacteria14:04

Biosensor for Detection of Antibiotic Resistant Staphylococcus Bacteria

Published on: May 8, 2013

25.3K

Related Concept Videos

Clinical Significance of Antibiotic Resistance01:25

Clinical Significance of Antibiotic Resistance

Methicillin-resistant Staphylococcus aureus (MRSA) presents a critical public health threat, arising from its capacity to resist β-lactam antibiotics due to acquisition of the mecA gene within the staphylococcal cassette chromosome mec (SCCmec). This gene encodes penicillin-binding protein 2a (PBP2a), which impairs binding efficacy of methicillin and other β-lactams. MRSA has evolved into distinct clonal lineages impacting humans and animals alike, reinforcing its significance within...
52
Mechanism of Antibiotic Resistance in MRSA01:25

Mechanism of Antibiotic Resistance in MRSA

Antibiotic resistance in bacteria arises when microorganisms evolve the ability to withstand drugs designed to kill them or inhibit their growth, rendering once-effective treatments useless. This phenomenon, driven by genetic change and selection under antibiotic exposure, poses a profound threat to modern medicine. Mechanisms include drug-inactivating enzymes (e.g., β-lactamases), efflux pumps that eject antibiotics, mutations altering antibiotic targets, decreased drug uptake, and...
132
Staphylococcal Skin Infections01:29

Staphylococcal Skin Infections

Staphylococcus aureus is a Gram-positive coccus that resides harmlessly on the skin and mucous membranes of healthy individuals. When the skin barrier is breached, it can shift from a commensal to an opportunistic pathogen. This transition is facilitated by surface adhesins, such as clumping factor B and S. aureus surface protein G (SasG), which bind to structural proteins, including loricrin and cytokeratin, in the damaged epidermis. Protein A, another key factor, binds the Fc region of...
89
Bacterial Gastroenteritis01:18

Bacterial Gastroenteritis

Bacterial gastroenteritis, characterized by diarrhea, abdominal cramps, and vomiting, is often caused by ingestion of contaminated food or water and is frequently associated with pathogenic Escherichia coli strains. These microbes exploit two principal mechanisms to inflict disease.Shiga toxin–producing E. coli, also referred to as STEC—notably O157:H7—release Shiga toxins that target ribosomes, blocking protein synthesis. The B subunit of the toxin binds the host glycolipid...
56
Development of Antibiotic Resistance01:30

Development of Antibiotic Resistance

Antibiotic resistance is a major public health concern that arises when bacteria evolve mechanisms to withstand the effects of antibiotic treatments. This resistance can be intrinsic, acquired through genetic mutations, or transferred between bacteria via horizontal gene transfer. The development of antibiotic resistance poses significant challenges in treating bacterial infections and necessitates ongoing research to develop new therapeutic strategies.Intrinsic resistance occurs when bacterial...
2.0K