Related Experiment Videos
Microbiological quality of ice in hospital and community
I G Wilson1, G M Hogg, J G Barr
1Northern Ireland Public Health Laboratory, Bacteriology Department, Belfast City Hospital Trust, UK.
Abstract:
A survey was undertaken in response to a report of a clinical infection which had been related to an ice-making machine on a hospital ward. A detailed study of the ice microflora of 27 ice-making machines was performed. In a subsequent survey, ice samples (N = 194) from establishments such as bars and hotels were examined for bacterial indicators of hygiene. Samples from hospital ice-making machines yielded low numbers of a wide range of potentially opportunistic micro-organisms, many of environmental rather than clinical origin. For ice sampled in the community, the total aerobic plate count (TAPC) at 37 degrees C for 95% of the samples was < 500 cfu/mL, and at 22 degrees C 75% had < 500 cfu/mL. Examination for coliforms showed that 69% of samples contained no coliforms, but 20% contained > 100 coliforms/100 mL. Escherichia coli was detected in three samples but in very low numbers. This report investigates the relevance of ice machines to the control of hospital infection, the hygiene of ice in the community, discusses the microbiological quality of ice and proposes possible guidelines.
Insights
Hospital ice machines can harbor opportunistic microbes, though community ice generally meets hygiene standards. Further investigation is needed on ice machines
Area of Science:
- Microbiology
- Hospital Infection Control
- Food Safety
Background:
- Clinical infections linked to hospital ice-making machines necessitate investigation.
- Microbiological quality of ice from both hospital and community sources requires assessment.
Purpose of the Study:
- To evaluate the microbiological quality of ice from hospital and community ice-making machines.
- To determine the potential role of ice machines in hospital-acquired infections.
- To assess the hygiene standards of ice in public establishments.
Main Methods:
- Detailed study of ice microflora from 27 hospital ice-making machines.
- Survey of 194 ice samples from community establishments (bars, hotels) for bacterial hygiene indicators.
- Microbiological analysis including total aerobic plate count (TAPC) and coliform testing.
Main Results:
- Hospital ice machines contained low levels of opportunistic microorganisms, primarily environmental.
- Community ice samples generally showed good hygiene: 95% < 500 cfu/mL (TAPC at 37°C).
- Coliforms were present in 20% of community samples (>100/100 mL), with rare detection of Escherichia coli.
Conclusions:
- Hospital ice machines pose a low risk for clinical infections, with microbes mainly of environmental origin.
- Community ice generally demonstrates acceptable microbiological quality, but monitoring for coliforms is warranted.
- Guidelines for microbiological quality of ice are proposed to ensure safety.