Staphylococcus aureus (MRSA) has become a prevalent nosocomial pathogen in the
United States. In hospitals, the most important reservoirs of MRSA are infected or
colonized patients. Although hospital personnel can serve as reservoirs for MRSA and may
harbor the organism for many months, they have been more commonly identified as a link for
transmission between colonized or infected patients. The main mode of transmission of MRSA
is via hands (especially health care workers' hands) which may become contaminated by
contact with a) colonized or infected patients, b) colonized or infected body sites of the
personnel themselves, or c) devices, items, or environmental surfaces contaminated with
body fluids containing MRSA. Standard Precautions, as described in the "Guideline for
Isolation Precautions in Hospitals" (Infect Control Hosp Epidemiol 1996;17:53-80),
should control the spread of MRSA in most instances.
Standard Precautions include:
- 1) Handwashing
- Wash hands after touching blood, body fluids, secretions, excretions, and contaminated
items, whether or not gloves are worn. Wash hands immediately after gloves are removed,
between patient contacts, and when otherwise indicated to avoid transfer of microorganisms
to other patients or environments. It may be necessary to wash hands between tasks and
procedures on the same patient to prevent cross-contamination of different body sites.
- 2) Gloving
- Wear gloves (clean nonsterile gloves are adequate) when touching blood, body fluids,
secretions, excretions, and contaminated items; put on clean gloves just before touching
mucous membranes and nonintact skin. Remove gloves promptly after use, before touching
noncontaminated items and environmental surfaces, and before going to another patient, and
wash hands immediately to avoid transfer of microorganisms to other patients or
- 3) Masking
- Wear a mask and eye protection or a face shield to protect mucous membranes of the eyes,
nose, and mouth during procedures and patient-care activities that are likely to generate
splashes or sprays of blood, body fluids, secretions, and excretions.
- 4) Gowning
- Wear a gown (a clean nonsterile gown is adequate) to protect skin and prevent soiling of
clothes during procedures and patient-care activities that are likely to generate splashes
or sprays of blood, body fluids, secretions, and excretions or cause soiling of clothing.
- 5) Appropriate device handling
- Handle used patient-care equipment soiled with blood, body fluids, secretions, and
excretions in a manner that prevents skin and mucous membrane exposures, contamination of
clothing, and transfer of microorganisms to other patients and environments. Ensure that
reusable equipment is not used for the care of another patient until it has been
appropriately cleaned and reprocessed and that single-use items are properly discarded.
- 6) Appropriate handling of laundry
- Handle, transport, and process used linen soiled with blood, body fluids, secretions,
and excretions in a manner that prevents skin and mucous membrane exposures, contamination
of clothing, and transfer of microorganisms to other patients and environments.
If MRSA is judged by the hospital's infection control program to be of special clinical
or epidemiologic significance, then Contact Precautions should be considered.
Contact Precautions consist of:
1) Placing a patient with MRSA in a private room. When a private room is not available,
the patient may be placed in a room with a patient(s) who has active infection with MRSA,
but with no other infection (cohorting).
2) Wearing gloves (clean nonsterile gloves are adequate) when entering the room. During
the course of providing care for a patient, change gloves after having contact with
infective material that may contain high concentrations of microorganisms (e.g., fecal
material and wound drainage). Remove gloves before leaving the patient's room and wash
hands immediately with an antimicrobial agent. After glove removal and handwashing, ensure
that hands do not touch potentially contaminated environmental surfaces or items in the
patient's room to avoid transfer of microorganisms to other patients and environments.
3) Wearing a gown when entering the room if you anticipate that your clothing will have
substantial contact with the patient, environmental surfaces, or items in the patient's
room, or if the patient is incontinent, or has diarrhea, an ileostomy, a colostomy, or
wound drainage not contained by a dressing. Remove the gown before leaving the patient's
room. After gown removal, ensure that clothing does not contact potentially contaminated
environmental surfaces to avoid transfer of microorganisms to other patients and
4) Limiting the movement and transport of the patient from the room to essential
purposes only. If the patient is transported out of the room, ensure that precautions are
maintained to minimize the risk of transmission of microorganisms to other patients and
contamination of environmental surfaces or equipment.
5) Ensuring that patient-care items, bedside equipment, and frequently touched surfaces
receive daily cleaning.
6) When possible, dedicating the use of noncritical patient-care equipment and items
such as stethoscope, sphygmomanometer, bedside commode, or electronic rectal thermometer
to a single patient (or cohort of patients infected or colonized with MRSA) to avoid
sharing between patients. If use of common equipment or items is unavoidable, then
adequately clean and disinfect them before use on another patient.
Culturing Of Personnel And Management Of Personnel Carriers Of MRSA
Unless the objective of the hospital is to eradicate all MRSA carriage and treat all
personnel who are MRSA carriers, whether or not they disseminate MRSA, it may be prudent
to culture only personnel who are implicated in MRSA transmission based on epidemiologic
data. MRSA-carrier personnel who are epidemiologically linked to transmission should be
removed from direct patient care until treatment of the MRSA-carrier status is successful.
If the hospital elects to culture all personnel to identify MRSA carriers, a) surveillance
cultures need to be done frequently, and b) it is likely that personnel colonized by MRSA
who are not linked to transmission and/or who may not be MRSA disseminators will be
identified, subjected to treatment, and/or removed from patient contact unnecessarily.
Because of the high cost attendant to repeated surveillance cultures and the potential of
repeated culturing to result in serious consequences to health care workers, hospitals
should weigh the advantages and the adverse effects of routinely culturing personnel
before doing so.
Control Of MRSA Outbreaks
When an outbreak of MRSA infection occurs, an epidemiologic assessment should be
initiated to identify risk factors for MRSA acquisition in the institution; clinical
isolates of MRSA should be saved and submitted for strain typing. Colonized or infected
patients should be identified as quickly as possible, appropriate barrier precautions
should be instituted, and handwashing by medical personnel before and after all patient
contacts should be strictly adhered to.
All personnel should be reinstructed on appropriate precautions for patients colonized
or infected with multiresistant microorganisms and on the importance of handwashing and
barrier precautions in preventing contact transmission.
If additional help is needed by the hospital, a consultation with the local or state
health department or even the CDC may be necessary.