Common Organisms Responsible for Healthcare-associated Infection (HCAI)
MRSA are S. aureus which become methicillin resistant by the acquisition of the mec A gene which is on a mobile chromosomal determinant called staphylococcal cassette chromosome mec (SCC mec). The mec A gene encodes for a penicillin- binding protein (PBP2a) which has a low affinity for isoxazolyl-penicillins (MICs to oxacillin/ meticillin ≥ 4μg/ ml) and is resistant to all classes of beta-lactam antibiotics. Current Department of Health (DOH) guidance (2014) recommends that mandatory MRSA screening be streamlined to include only: ● All patient admissions to high- risk units; ● Healthcare workers; and ● All patients previously identified as colonized or infected with MRSA. The guidance also advises Trusts to follow local risk assessment policies to identify other potential high- risk units or units with a history of high endemicity of MRSA; and The guidance also recommends regular auditing of compliance with MRSA screening policy. The 2006 guideline for the control and prevention of MRSA in healthcare facilities recommends the following four measures. ● Isolation MRSA- positive patients should be nursed in a single room or if none is available, cohorting into a bay after risk assessment. Patient movement, and the number of staff and visitors looking after the patient, should be minimized. ● Hand hygiene and use of personal protective equipment (PPE) All staff and visitors should decontaminate their hands with soap and water/or an alcohol rub before and after contact with the patient or their immediate surroundings. Single-use disposable gloves and aprons/non- permeable gowns should be used by staff and visitors if there is a risk of contamination with body fluids. ● Disposal of waste and laundry All waste from colonized/ infected patients should be placed in the infectious waste stream. All linen and bedding from patients colonized/infected with MRSA should be considered as contaminated and processed as infected linen. ● Cleaning and decontamination The patient’s room should be cleaned/disinfected daily with an appropriate detergent/disinfectant as per local policy. On discharge of the patient, the room needs to be terminally cleaned before it is reused. All patient equipment should either be single-patient use or be cleaned, disinfected, and sterilized.