BOISE, Idaho — A health advisory for Hells Canyon Reservoir was issued by Southwest District Health due to cyanobacteria.

The advisory for the reservoir is issued from Copper Creek to Hells Canyon Dam.

Officials urge people to be careful when near or in the water in the area.

Samples taken showed high concentrations of the toxin-producing cyanobacteria, which can be harmful to pets, livestock and people, according to officials.

Symptoms caused by cyanobacteria include rashes, hives, diarrhea, vomiting, coughing and wheezing. More serious symptoms also affect the liver and nervous system.

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Health officials say people should avoid swimming or getting into the water in general, don't drink or cook with water from the reservoir and wash your hands after handling fish that were caught in the affected water. Fish caught from the reservoir should also be thoroughly cleaned and prepared before consuming.

Blooms of cyanobacteria may appear as mats, foam, spilled paint or scum and have a strong odor, according to officials.

MORE: Health advisory issued after cyanobacteria found in Ada, Elmore reservoirs