Legionnaires disease

• 135 cases of legionellosis notified, similar to the annual total for 2016 (136 cases).
• Cases were mainly caused by two Legionella species: L. pneumophila (81) and L. longbeachae (48).
• All cases were carefully interviewed to identify possible exposure sources. When possible clusters of cases with a common exposure were identified environmental investigations were conducted. Although a number of possible clusters were investigated there were no likely common exposure sources identified.
• Actioning the recommendations of an expert panel, and publishing the first set of amendments to the Public Health Act Regulation 2012, requiring mandatory monthly testing of all water-cooling system for Legionella bacteria. (Further amendments to the Regulation were introduced in 2018).

For further information about​​ Legionella epidemiology see Legionnaires’ disease.