Assessing environmental contamination in Dutch and Belgian nursing homes: a cross-border ATP-based study

BACKGROUND: To reduce the spread of micro-organisms in nursing homes adequate measurement of cleaning is necessary. ATP measurements can be a helpful tool in quantifying contamination.

AIM: To objectively measure environmental contamination within multiple nursing homes, such that cleaning can be focused on the most contaminated fomites.

METHODS: Standardized ATP measurements were conducted in 28 nursing homes on multiple wards. Fifteen pre-defined surfaces per ward were measured with the 3M Clean Trace NG luminometer. Results are displayed in relative light units (RLU). RLU >1000 was considered as 'not clean'. Differences in RLU values were compared between countries and fomite groups.

FINDINGS: A total of 1794 ATP measurements were performed, ranging from 28 up to 202 per nursing home. The median RLU value was 1037 (range: 1-376,880) and 51.3% of the measurements had RLU values >1000. There were significant differences between countries and fomite groups.

CONCLUSION: ATP measurements can be used as an objective approach to determine the level of environmental contamination in nursing homes. Significant differences in ATP levels were found between nursing homes and countries. Moreover, pronounced differences were found between fomite groups. These findings offer potential targets for improvement of cleanliness within nursing homes.