Novel Detection Assay of Methicillin-Resistant Staphylococcus aureus Directly from Clinical Samples


Staphylococcus aureus (SA) is a Gram-positive anaerobe frequently present in the natural human microbiota of the nose and skin that can cause a range of illnesses, from minor skin infections and food poisoning to life-threatening diseases such as pneumonia, toxic shock syndrome and sepsis. Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most important multidrug-resistant nosocomial pathogens worldwide with infections leading to high rates of morbidity and mortality, a significant burden to human and veterinary clinical practices. Treatment and control of MRSA infection is associated with annual healthcare costs of about $3 billion dollars a year.  

In a clinical setting, the samples from potential MRSA patients can be highly heterogeneous, making it difficult to detect by conventional antimicrobial susceptibility test methods. With limited treatment options, early detection and infection control practices such as isolation are necessary to help control of spread of MRSA. However current available PCR-based assays are problematic in that they produce false positive and false negative results, neither are they able to detect new emerging genetic variants.

Description of Technology

A researcher from the University of Calgary has developed a novel scheme for the direct detection of MRSA from clinical samples. This 2-step PCR-based assay can circumvent false positive and false negative issues of current available commercial assays, while providing less than a 10 hour turn-around detection time and convenience of working directly from clinical samples.

Areas of Application

Non-invasive, quick detection of MRSA in healthcare-associated and community-associated infections from:

  • Clinical samples for point-of-care tests
  • Cultured samples for lab-based tests
IP Status

Patent pending (provisional application filed)

Competitive Advantages

The currently available tests produce 1) false negatives from their inability to detect new variants, and 2) false positives from the inability to differentiate pathogenic and less pathogenic Staphylococcus aureus strains. Our invention solved the above problems and provided 100% accuracy in detecting multiple variants:

Clinical Strains (total n=218) % Accuracy of Detection
MRSA (pathogenic) MRSA (100%)
Methicillin Sensitive SA (MSSA, non-resistant) SA but non-MRSA (100%)
MR - coagulase negative staphylococci (less pathogenic) MR but non-MRSA (100%)
MS - coagulase negative staphylococci (non-resistant, less pathogenic) Non-MRSA (100%)
Stage Of Development
  • Assay has been validated on a cohort of 218 clinical isolates
  • Innovate Calgary is seeking licensee to develop this test into a lab-based assay