Water, Sewage & Effluent January-February 2017 - Page 30

Editor ’ s comment
The Legionella Action Group has just released a report on the outbreak of legionnaires ’ disease in South Africa , which we will publish in the next issue . The point is that a disease that we thought was long gone has returned . Let us hope that the authorities , designers , planners , legislators , and installers do not wait for an epidemic to occur before applying two simple rules : ( 1 ) Ensure that standards are applied ; and ( 2 ) Forget any shortcutting in favour of profit and at the expense of the public , which we all purport to protect , except for unqualified professionals , plumbers and unscrupulous suppliers .

The US Environmental Protection Agency ( EPA ) developed this document because it recognises that many species of the genus legionella are a public health threat . The EPA recognises that many facility managers are choosing to install treatment systems to prevent or mitigate legionella growth in their premise plumbing systems . The target audience for this document includes , but is not limited to , primacy agencies , facility operators , facility owners , technology developers , and vendors .

This document summarises peer-reviewed scientific literature , reports from nationally and / or internationally recognised research organisations , and guidelines and standards from nationally and / or internationally recognised organisations . The reviewed literature characterises the effectiveness of different technologies that may be used to control legionella growth in premise plumbing systems . Particularly , it focuses on premise plumbing systems of large buildings , such as hotels , hospitals , schools , and other buildings with complex plumbing infrastructure .
The EPA expects this document will improve public health protection by helping the target audience make better informed , science based risk management decisions to control legionella growth in buildings .
Background
Legionella is a bacterium that can be found throughout the world , mostly in aquatic and moist environments , such as lakes , rivers , groundwater and soil . The infection caused by legionella is known as legionellosis and occurs primarily in two forms :
• Legionnaires ’ disease , which is a type of pneumonia ( Fraser et al ., 1977 ).
• Pontiac fever , which is a milder flu-like illness without pneumonia ( Kaufmann et al ., 1981 ; Glick et al ., 1978 ).
The disease can be acquired by inhaling or aspirating aerosolised water or soil ( potting soil , compost soil ) contaminated with legionella ( Travis et al ., 2012 ). No infection associated with animalto-person contact , consumption of contaminated food , or ingestion of contaminated water has been reported . Only one probable case of person-to-
28 Water Sewage & Effluent January / February 2017