Adherence to Legionella control regulations and guidelines in Norwegian nursing homes: a cross-sectional survey

Infection by Legionella bacteria is a risk to elderly individuals in health care facilities and should be managed by preventing bacterial proliferation in internal water systems. Norwegian legislation calls for a mandatory Legionella-specific risk assessment with the subsequent introduction of an adapted water management programme. The present study investigates adherence to legislation and guidelines on Legionella control and prevention in Norwegian nursing homes.

A cross-sectional survey was distributed to Norwegian municipalities to investigate the status of Legionella specific risk assessments of internal water distribution systems and the introduction of water management programmes in nursing homes.

A total of 55.1% (n = 228) of the participating nursing homes had performed Legionella-specific risk assessments, of which 55.3% (n = 126) stated that they had updated the risk assessment within the last year. 96.5% introduced a water management programme following a risk assessment, whereas 59.6% of the ones without a risk assessment did the same. Nursing homes with risk assessments were more likely to monitor Legionella levels than those without (61.2% vs 38.8%), to remove dead legs (44.7% vs 16.5%), and to select biocidal preventive treatment over hot water flushing (35.5% vs 4.6%).

This study presents novel insight into Legionella control in Norway, suggesting that adherence to mandatory risk assessment in nursing homes is moderate-low. Once performed, the risk assessment seems to be advantageous as an introduction to future Legionella prevention in terms of the scope and contents of the water management programme.