An epidemiological survey of methicillin- resistant Staphylococcus aureus in a tertiary referral hospital

• Published in: The Journal of hospital infection Vol. 44; no. 1; pp. 19 - 26
• Main Authors: Barakate, M.S., Yang, Y-X., Foo, S-H., Vickery, A.M., Sharp, C.A., Fowler, L.D., Harris, J.P., H.West, R., Macleod, C., Benn, R.A.
• Format: Journal Article
• Language: English
• Published: Kent Elsevier Ltd 01-01-2000; Elsevier
• Subjects: Adolescent; Adult; Aged; Aged, 80 and over; Australia; Bacterial diseases; Biological and medical sciences; Child; Child, Preschool; Cross Infection - epidemiology; Cross Infection - microbiology; Cross Infection - transmission; epidemiology; Female; Health Policy; hospital infections; Hospitals, Teaching; Human bacterial diseases; Humans; Incidence; Infant; Infant, Newborn; Infection Control; Infectious diseases; Male; Medical sciences; Methicillin Resistance; Methicillin-resistant Staphylococcus aureus; Middle Aged; New South Wales - epidemiology; Prospective Studies; Staphylococcal Infections - epidemiology; Staphylococcal Infections - microbiology; Staphylococcal Infections - transmission; Staphylococcal infections, streptococcal infections, pneumococcal infections; Staphylococcus aureus; Staphylococcus aureus - isolation & purification; New South Wales; Australia; epidemiology; Methicillin-resistant Staphylococcus aureus; hospital infections; Human; Nosocomial infection; Typing; Epidemiology; Monthly variation; Incidence; Infection; Microbiological investigation; Health policy; Bacteriosis; Hospital ward; Bacteria; Micrococcales; Micrococcaceae; Hospital; Staphylococcal infection; Sanitary surveillance; Colonization; Staphylococcus aureus
• ISSN: 0195-6701; 1532-2939
• DOI: 10.1053/jhin.1999.0635

Over a 30-month period from July 1995 to December 1997, new detections of methicillin-resistantStaphylococcus aureus (MRSA) were prospectively studied in a tertiary referral hospital. The aims of the study were to determine the incidence of colonization of patients admitted to each of the hospital’s 39 clinical units and ascertain where each patient had become colonized. Epidemiological information (time to detection, ward movement, admission to other hospitals, data on MRSA isolations in hospital wards) and phage typing were used by the hospital’s infection control unit to make this determination. Routine containment procedures included cohorting, flagging and triclosan body washes. Surveillance cultures were collected infrequently. Patients known to be colonized with MRSA were excluded from orthopaedic and haematology wards. During the study period, 995 patients were found to be newly colonized. The incidence of colonization varied from nil to 72 per 1000 admissions, being highest in the main intensive care unit and in services which frequently used that unit. The incidence of colonization in elective orthopaedic surgery (< 1 per 1000) and haematology (3 per 1000) was very low. Determining the place where patients acquired MRSA was made difficult by the high frequency of endemic phage types and frequent patient transfer between wards. Epidemiological data suggested that the main intensive care unit and surgical wards nursing patients with colorectal, urological and vascular diseases were the places where most patients became colonized. MRSA was never acquired by patients nursed in wards which practised an exclusion policy towards patients known to be colonized with MRSA. Our data suggest that in tertiary referral hospitals, where MRSA is not only endemic but frequently imported from other hospitals, it is possible to establish areas where MRSA is never acquired.