Blue-Green Algae Exposure

Summer will be here before we know it. With it comes warm weather perfect for hiking, outdoor sports, and long walks with the dogs. You may be tempted to let your four-legged kid run free in a park and swim in the local lake. But what happens if that pond or lake contains blue-green algae?

Blue-green algae is a type of cyanobacteria that is found in fresh and brackish (not quite fresh and not quite salt) water. It is found all over the world, including throughout most of the US. Large amounts of blue-green algae have the capability to aggregate on the surface of water which is a major health concern for animals that come in contact with it. Exposure may be through swimming or drinking the water.

There are many different types of toxins that may be present in blue-green algae blooms. These can cause major issues with the liver, skin, and even the brain. Your pet may develop the following symptoms: vomiting/diarrhea, weakness, tremors/seizures, excessive salivation, respiratory distress, itchiness, blisters, and more. It may progress to liver failure, which could be fatal.

If your animal comes in contact with unfamiliar bodies of water and begins to display any of the mentioned symptoms, it is best to seek immediate veterinary care. If it is a true blue-green algae toxin exposure, it may be a long road to recovery, even if caught early.

Blue-green algae can be difficult to distinguish from other types of algae. Check with your state to see if there are documented presence of it locally.

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Written by:

Allyson Witt, Pet Poison Helpline DVM student extern, Iowa State University, Class of 2023
And Samantha Koch, CVT Pet Poison Helpline