Quarterly Report
Methicillin Resistant Staphylococcus aureus (MRSA) bacteraemia
Third Quarter 2011
September 2011 to December 2011
Number of new cases of healthcare associated infection = 0
Number of patient days = 11,645
Infection rate = 0/ 11,645 x 1,000 = 0
MRSA Rate Calculation
The method of calculation of the MRSA bacteraemia infection rate for the reporting period (on a quarterly basis) is:
Number of nosocomial patients with laboratory identification of MRSA bacteraemia x 1000
Total number of patient days
Where the numerator is the total number of newly identified cases for MRSA bacteraemia associated with the reporting facility, for the reporting period. The denominator is the total number of in-patient days for the reporting period. There are no exclusion criteria.
What is Methicillin-resistant Staphylococcus aureus (MRSA)?
MRSA is a type of bacteria that is resistant to certain or all types of the beta-lactam classes of antibiotics such as penicillins, penicillinase-resistant penicillins (e.g. cloxacillin) and cephalosporins. MRSA are strains of S. aureus that have an MIC to oxacillin of ≥ 4 mcg/ml. or contain the mecA gene coding for penicillin binding protein 2a (PBP 2a).
What does hospital-acquired mean?
Sometimes when patients are admitted to the hospital, they can get infections. This is a hospital-acquired infection. In the case of MRSA, this may mean that symptoms begin 72 hours after admission to the hospital.
What are the risk factors for MRSA?
Risk factors for MRSA acquisition include invasive procedures, prior treatment with antibiotics, prolonged hospital stay, stay in an intensive care or burn unit, surgical wound infection and close proximity to a colonized person. MRSA can also be transmitted from mother to child through breast milk.
How is MRSA transmitted?
The single most important mode of transmission of MRSA in a health care setting is via transiently colonized hands of health care workers who acquire it from contact with colonized or infected patients, or after handling contaminated material or equipment. The unrecognized colonized patient presents a particular risk for transmission to other patients.