Evaluation of a National Legionella Prevention Program at Veterans Health Administration (VHA) Medical Facilities

Background: In 2008, VHA Directive policy indicated that VHA inpatient facilities and Community Living Centers (CLC; formerly known as nursing homes) implement an annual plan to evaluate risk for and provide a means to prevent healthcare-associated Legionella disease (HCA LD).  The Directive provided algorithms for plan development that factored in facility type, history of HCA LD, water treatment and need for surveillance screening of water and patients for Legionella.  Guidance included triggers for mitigation activities. This national policy for active evaluation of Legionella risk is one of the largest such initiatives in a healthcare system in the United States. 
Objective: To assess the first annual Legionella evaluation conducted in 2008 by VHA facilities nationwide.

Methods: In 2009, VHA conducted a survey of all VHA facilities required to have a Legionella evaluation plan in accordance with the Directive.  The survey included questions on facility characteristics, Legionella testing and disease, choices made by facilities for implementing the Directive, and local findings from Legionella surveillance and mitigation activities.

Results: 171 facilities completed the survey (95% response).  Facilities identified their facility type as acute inpatient care (64%), CLC (23%), transplant center (6%), and post-transplant care (7%).  Forty-two percent reported using monochloramine-treated water.  The number of Legionella urinary antigen tests performed for facilities in 2008 ranged from 0 (29 facilities) to 663.  The number of clinical cultures for Legionella in 2008 ranged from 0 (110 facilities) to 545.  Three facilities reported a total of 6 cases of HCA LD in 2008. By following the algorithms, almost 60% of facilities identified a need for surveillance screening: 49 facilities chose environmental water testing, 30 did clinical screening and 23 did both.  While facilities varied in the number of distal water sites tested for environmental screening (interquartile range= 6 to 15), most facilities followed guidance for triggers for further action.  Eighteen facilities (11%) indicated that an action plan was needed to mitigate for Legionella.  Reasons for mitigation were: a history of HCA LD (8 facilities), positive water surveillance results (9 facilities), or both (1 facility).  Six facilities needed to repeat mitigation due to persistence of Legionella in the water system.

Conclusions: The Legionella prevention Directive provided uniform guidance for VHA facilities to evaluate local Legionella disease and risk, and allowed for coordinated national assessment.  Implementation of the Directive targeted 18 facilities for Legionella mitigation that may prevent HCA LD.  Survey results will be used to focus follow-up education and guidance to facilities.