Risks of Blue-green Algae

At various times over the last several years, the Wisconsin Department of Natural Resources has confirmed the presence of blue-green algae in Lake Petenwell, Castle Rock Lake, Lake Sherwood, Lake Camelot, and Lake Arrowhead in Adams County.  Illnesses in humans and animals potentially related to blue-green algae in these lakes have been reported as well.

Links to important information about managing the risk of illness related to contact with blue-green algae.

Health Risks of Contact With Blue-Green Algae

“Swimming in or swallowing water with high levels of blue-green algae presents health risks to individuals,” says Sarah Grosshuesch, Adams County Health Officer. “Awareness and common sense is the key. People and their pets should avoid swimming where water looks like pea soup or smells foul.” All recreation swimmers and boaters are warned to avoid direct contact with the affected lake areas.

Algae blooms take on many different appearances and colors. They can look like pea soup or spilled paint on the surface of the water. Although the color is usually blue-green the algae blooms can range from blue to red in color. There is currently no treatment for blue-green algae blooms so it is best to stay out of the water until the bloom dissipates on its own. Although many adults will avoid swimming in such conditions, children and pets are less conscious of where they chose to swim. It is important to protect children and pets from the threat of blue-green algae by making sure they avoid contaminated waters.

According to the U.S. Center for Disease Control and Prevention (CDC), adverse human health effects include difficulty breathing, stomach and intestinal issues such as vomiting and diarrhea, skin irritation, loss of appetite, nausea, or numbness or tingling of the hands and/or feet. These symptoms can show up minutes to hours after exposure. Pets, especially dogs, can experience symptoms such as fatigue, difficulty breathing, vomiting, convulsions, and even death following exposure to blue-green algae. Health officials recommend if you or your pets have been exposed to blue-green algae and are experiencing any of these symptoms to seek medical or veterinary attention.

The Wisconsin Department of Natural Resources offers tips to protect you and your family:

  • Do not swim in water that looks like “pea soup”, green or blue paint, or that has a scum layer or puffy blobs floating on the surface
  • Do not boat, water ski, etc. over such water (people can be exposed through inhalation of aerosolized water droplets)
  • Do not let children play with scum layers, even from shore
  • Do not let pets or livestock swim in, or drink, waters experiencing blue-green algae blooms
  • Do not treat surface waters that are experiencing blue-green algae blooms with any herbicide or algaecide– toxins are released into the water when blue-green algae cells die
  • In general, avoid swimming in areas where you cannot see your feet in knee-deep water
  • Always take a shower after coming into contact with any surface water (whether or not a blue-green algae bloom appears to be present; surface waters may contain other species of potentially harmful bacteria and viruses)

If you think you, a family member, or pet developed an illness after exposure to blue-green algae, please report the illness to the Wisconsin Division of Public Health by filling out an online survey HERE or calling (608) 266-1120.

Examples of Blue-Green Algae

Algae Reaction Symptoms

Algae Reaction Symptoms Mimic Common Problems

By Reesa Evan,  Lake Specialist Adams County Land & Water Conservation Department

Did you go swimming and start coughing a couple of hours later? Go waterskiing, jet-skiing or tubing and feel a little tired? Go boating and feel nauseated? All of these symptoms could be just an everyday thing – or they could be symptoms of contact with potentially-toxic blue-green algae. Many people don’t realize they are having such a reaction because the symptoms mimic common problems.

Blue-green algae are ordinary and necessary for our lakes, streams and rivers. However, some blue-green algae (also called cyanobacteria) can become toxic and cause many symptoms (even death in extreme instances) to both humans and animals. Exposure can occur through skin contact, inhalation (breathing in) and/or ingestion (swallowing).

The State of Wisconsin has started a program to try to track negative consequences of contacts with algae. If you think you or others (including pets) have symptoms from such contact, you should call 608-266-1120 or fill out a report online HERE. You will be contacted shortly by someone from the program to get details and schedule further action.

The most common potentially-toxic types in Wisconsin are Anabena, Aphanizomenon, Microcystis and Oscillatoria. The first three are often “Annie, Fannie and Mike”. Common symptoms caused by exposure to these bacteria are:

  • Skin irritations such as rashes or hives
  • General body reactions such as fever, diarrhea, coughing, general throat irritation, runny nose,
    vomiting, nausea, headache, muscle/joint pain
  • In severe cases, convulsions/seizures, paralysis, respiratory failure, even death

To avoid these problems, use common sense:

  • If the water looks scummy, has a large mat of gunk or otherwise looks iffy, avoid contact
  • Don’t let children or pets play in shallow, scummy areas or where algae blooms are present
  • Avoid jet-skiing, waterskiing or tubing over mats of algae
  • Don’t use raw, untreated water for drinking, cleaning food or washing gear
  • Don’t boil contaminated water, as this may release more toxins from the algae
  • After family members come into contact with water that may be contaminated. Wash
    thoroughly, especially in areas covered by swimsuits (which may concentrate the algae)
  • Thoroughly wash any clothing or fabric that has come into contact with the water
  • If your pet or livestock come into contact with such water, wash the coat to prevent the animal
    from taking potentially-toxic algae in while self-cleaning