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. Harmful algae or cyanobacteria 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.
Protect Yourself and Pets
Learn how to check for health advisories, report blooms, and prevent blooms from forming.
Information for Animal Owners
Take steps to protect your pets and livestock from deadly toxins made by cyanobacteria (blue-green algae).
Find information for animal owners, healthcare providers, veterinarians, and poison center professionals.
Publications, Data, and Statistics
Find journal articles, reports, and other information on blooms and illnesses.
Use CDC materials to raise awareness and prevent illness:
- Fact sheets
- Social media messages
- Partner toolkit
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