Are hygiene standards useful in assessing infection risk?

Area of Science:

• Infection control
• Environmental hygiene
• Microbiology

Background:

• Assessed surface cleanliness in a 5-bed surgical intensive care unit (SICU) over 10 weeks.
• Evaluated proposed hygiene standards for environmental monitoring.

Purpose of the Study:

• To evaluate proposed hygiene standards for surface cleanliness in a SICU.
• To assess the relationship between environmental contamination and patient activity.

Main Methods:

• Monitored 10 environmental sites in the SICU twice weekly.
• Collected clinical and patient activity data.
• Defined hygiene failure by aerobic colony counts (ACCs) > 2.5 CFU/cm² and presence of Staphylococcus aureus.

Main Results:

• Nearly 25% of samples failed to meet standards, primarily from hand-touch surfaces.
• Hygiene failures correlated with bed occupancy and showed a trend with SICU-acquired infections.
• Staphylococcus aureus found in the environment was linked to bed occupancy, with evidence of bidirectional patient-environment transmission.

Conclusions:

• Microbial-based hygiene standards effectively reflect patient activity and aid infection risk management.
• An environmental Staphylococcus aureus reservoir poses a tangible risk to patients.
• Surface cleanliness standards require further investigation and validation.