Manage a site investigation for travel-associated Legionnaires disease
Source: gov.uk (2025-07-15)

Documentation to assist the public health response in the management of accommodation sites associated with one or more cases of Legionnaires’ disease.

This content was originally produced by Public Health England (PHE). This content is now owned and managed by the UK Health Security Agency (UKHSA).

Travel-associated Legionnaires’ disease

One of the objectives for the national surveillance scheme is to monitor and detect clusters and outbreaks of Legionnaires’ disease associated with commercial accommodation sites. This includes travel within the UK and abroad. While all travel abroad is reported directly to the national focal points in the country of travel, it is also necessary to ensure that all accommodation sites in England associated with one or more cases of Legionnaires’ disease are monitored and where necessary, appropriate actions taken to risk assess sites and implement control measures.

The checklist and form above can be used to guide and document these actions, as explained below.

Single accommodation sites: 10-point approach for reducing the risk of Legionnaires’ disease

All accommodation sites associated with a single case of Legionnaires’ disease should be contacted by local environmental health authorities and issued with a document specifically for owners or managers of accommodation sites. The document outlines a 10-point approach to reduce the risk of Legionnaires’ disease. This is to remind owners or managers of their legal requirements in managing their water systems to ensure the health and safety of their employees and guests.

The enforcing agency for the premises may request further investigations or measures in addition to the accommodation site reviewing this document.

Cluster accommodation sites: Legionella incident reporting form

To assist all owners or managers of commercial accommodation sites in maintaining a high level of water system management, it is recommended that a site associated with 2 or more cases of Legionnaires’ disease within a 2-year period be risk assessed by local environmental health or health and safety agency (depending on which agency is responsible for enforcement of the site). The outcome of the risk assessment should then be followed up with necessary control measures.

The ‘Cluster accommodation sites: Legionella incident reporting form’ can be used as a resource for local Environmental Health officers, in addition to their own knowledge and skills, to carry out and record the findings of a risk assessment carried out at a commercial accommodation site, and followed by a record of actions and outcomes of remedial measures implemented.

The report is divided into 2 parts:

Part 1: Risk assessment – with a recommended 2-week period within which to carry out a full risk assessment of the site.

Part 2: Control measures – recommended to be completed within a further 4 weeks of the cluster being identified. This time period should allow for sampling to be carried out and results obtained and for remedial actions to have commenced.

The enforcing agency for the premises may request further investigations or measures as per the local investigation, in addition to any included within this document and should not be regarded as being equivalent to a minimum standard of investigation.