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Preventing Harmful Algal Blooms and Cryptosporidium Spread in Recreational Water: Quick Guides for Health Departments

Jul 23, 2024 | Rebecca Rainey

July is Lakes Appreciation Month! In order to support safe recreational water use, the National Association of County and City Health Officials (NACCHO), with support from the Centers for Disease Control and Prevention (CDC), presents two new quick guides for local, state, tribal, and territorial health departments. These quick reference guides can be used as a tool for understanding important recommendations for preventing exposure to freshwater harmful algal blooms (HABs) in recreational water and reducing the spread of Cryptosporidium in aquatic venues.

HABs are the overgrowth of toxin-producing algae or cyanobacteria that affect water quality and can cause harm to people, animals, and the environment. This quick guide contains important recommendations for identifying, detecting, and preventing exposure to freshwater harmful algal blooms (HABs) in recreational water.

Cryptosporidium is a microscopic parasite that causes a diarrheal illness called cryptosporidiosis. It can be found in freshwater, food, soil, or contaminated surfaces and is the leading cause of outbreaks linked to aquatic venues in the United States. This quick guide contains recommendations for reduction of its spread from CDC’s 2023 Model Aquatic Health Code (MAHC), a voluntary set of guidelines intended to prevent injury and illness at public aquatic venues.

Access the guides:

Quick Guide - Harmful Algal Blooms

Quick Guide - Cryptosporidium

NACCHO and CDC are committed to supporting local health departments to improve and maintain recreational water safety through the MAHC Network, a community of MAHC users, subject matter experts, and those interested in the code. Members will receive code updates and resources, provide input on new resources, and access webinars and other resources featuring the code and its users.

Visit the MAHC webpage (naccho.org/mahc) to explore more resources and to join NACCHO’s e-newsletter.


About Rebecca Rainey

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