Harmful Algal Bloom-Associated Illnesses
Harmful algal blooms are the rapid growth of algae or cyanobacteria that can cause harm to people, animals, or the local ecology. A harmful algal or cyanobacterial bloom can look like foam, scum, paint, or mats on the surface of water and can be different colors. These blooms can produce toxins that make people and animals sick. Blooms occur in fresh water, such as lakes and rivers, and salt water, such as oceans or bays.
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Page last reviewed: December 11, 2020
Content source: Centers for Disease Control and Prevention