Outbreaks of waterborne illness, like Legionnaires’ disease, have been on the rise over the last several years. An outbreak associated with recreational water is defined as the occurrence of similar illness in two or more persons whose illness are epidemiologically linked by location and time of exposure to persons using recreational water. The CDC recently published in their Morbidity and Morality Weekly Report (MMWR) a report on Outbreaks Associated with Treated Recreational Water in the United States from 2015 through 2019. The report covers important statistics about waterborne illness outbreaks occurrences and recommend implementing new Legionella control guidelines. From 2015-2019, there were over 208 outbreaks in 36 states that were associated with treated recreational water. The outbreaks resulted in 3,646 cases of illness, 286 hospitalizations and 13 deaths. Among the 208 outbreaks, 71 (34%) were associated with a hotel or a resort, and 107 (51%) started during June–August. 42% of the outbreaks were caused by Legionella, the bacteria that causes Legionnaires’ disease. While only 42% of these outbreaks were caused by Legionella, 100% of the deaths were due to Legionnaires’ disease. This shows that Legionnaires’ disease is one of the most serious risks posed to people by recreational water. Legionella is a bacterium that can be controlled with simple maintenance by the owners of recreational water facilities. Due to its nature, Legionella thrives in hot tubs. Legionella can amplify rapidly when disinfectant concentration is not properly maintained, when biofilm is present, or the water is not replaced frequently enough. The CDC concludes that adopting the CDC’s Model Aquatic Health Controls (MAHC) Legionella tool kit can greatly reduce the risk of Legionnaires disease. [1] Click here for a free consultation with Jules Zacher. For more information on Legionnaires’ disease, check out the National Academies of Sciences Management of Legionella in Water Systems Report Here. THE MATERIALS ON THIS WEBSITE HAVE BEEN PREPARED BY JULES ZACHER, P.C. FOR INFORMATIONAL PURPOSES ONLY AND ARE NOT LEGAL ADVICE OR A SUBSTITUTE FOR LEGAL COUNSEL. [1] To read the CDC’s Morbidity and Morality Weekly Report (MMWR) on Outbreaks Associated with Treated Recreational Water click here.