LCHD: Watch out for blue-green algae, swimmer’s itch this summer

For the Tomahawk Leader

LINCOLN COUNTY – The Lincoln County Health Department (LCHD) is reminding the public to watch out for blue-green algae and swimmer’s itch this summer.

“Summer is here, and that means more time to enjoy our area’s beautiful waterways,” LCHD stated in a release. “Although warmer temperatures and sunshine are welcomed, this weather creates the perfect conditions for algal blooms to develop, some of which can be harmful to humans and pets when swallowed, touched or inhaled.”

LCHD said many species of algae are found in are lakes and rivers and are a vital part of waterways.

“However, blue-green algae are not true algae,” LCHD explained. “Blue-green algae are actually bacteria known as cyanobacteria.”

“Risk for blue-green algae increases after heavy rain, causing agricultural and residential fertilizers to run off into our waterways,” said Mike Mandli, LCHD Environmental Health Specialist. “These added nutrients to our water, combined with little wind, warm temperatures and sunlight can create ideal conditions for blue-green algae to grow. If it looks like split-pea soup, it is important to stay out. These conditions typically occur in Lincoln County during mid-June through mid-September. It is important to always be aware – just because it doesn’t look like blue-green algae, doesn’t mean it isn’t in the water.”

Blue-green algae’s color is often described as pea soup or spilled green paint, but it can also be other colors, including white, red or brown.

Blue-green algae grows most abundantly in warm, calm, sunny weather with water temperatures above 75°F.

Blue-green algae’s color is often described as pea soup or spilled green paint, but it can also be other colors, including white, red or brown. Photo courtesy of LCHD.

“When conditions are just right, blue-green algae can grow quickly and create blooms,” LCHD said. “Blooms may produce a bad odor. It can be difficult to tell whether an algae bloom is dangerous or not, so it is best to treat all algae as dangerous, and when in doubt, stay out.”

Upon arriving to a beach or body of water, LCHD recommends looking for any postings and water quality notices before swimming. Before entering the water, do a visual inspection of the water to look for any signs of blue-green algae.

  • Do not swim or wade through areas with algal scums.
  • Do not boat, water ski or jet ski through algal blooms.
  • Do not fish in lakes where algal scum is present.
  • Always shower off with soap and water after swimming.

LCHD noted that pets are especially susceptible to blue-green algae.

“Because of their relatively small size, animals do not need to swallow very much contaminated water to become ill,” LCHD stated. “If you think your pet may have come into contact with any blue-green algae, rinse them off right away, do not let them lick the algae off and contact a veterinarian right away.”

Contact your healthcare provider if you were exposed to blue-green algae and are experiencing the following symptoms: Sore throat, red skin, runny nose, hives, cough, earache, difficulty breathing, headache, itchy eyes, stomach pain, itchy skin and vomiting.

“Another thing to watch out for this summer is swimmer’s itch,” LCHD said. “It is an infection caused by a parasite in bodies of water such as ponds, lakes and oceans. Swimmer’s itch causes an allergic reaction and a rash on your skin. Most cases of swimmer’s itch do not require medical attention. There is no way to know how long the water will be unsafe, so when in doubt, stay out. You may experience symptoms within minutes to days after swimming in contaminated water.”

Symptoms of swimmer’s itch can include small, reddish pimples or blisters; and tingling, burning or itching of the skin.

Visit the Wisconsin Department of Natural Resources (DNR) website ( to learn how to report a blue-green algae bloom, as well as for a list of beach closings and advisories and general safety tips.

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