Illness and Symptoms

Some cyanobacteria (also called blue-green algae) and algae can produce toxins that can make people and animals sick. Learn more about illnesses and symptoms caused by harmful cyanobacteria and algae based on where each one is most likely to be found.

Cyanobacteria in Fresh Water
cyanobacteria fresh water

Find information about illness and symptoms caused by harmful cyanobacteria.

Marine (Saltwater) Algal Blooms
Marine (Saltwater) Algal Blooms

Find information about illness and symptoms caused by harmful algae.

Page last reviewed: March 10, 2021