Itching to swim? Beware of parasite in local lakes
Swimmer's itch, like sunburns, can be one of the bummer side effects of a glorious summer day spent in the lake.
If you've spent time in Minnesota lakes over the years, it's likely you've heard, or told, a version of this person's account of swimmer's itch: "I got horrible lake itch while floating with my sister on Lake Carlos, on or around July 1. As my arms dangled in the water, I received over 70 bites on both forearms. I didn't sleep for days. I tried several home remedies such as peroxide, baking soda paste and calamine spray, which did not touch the bites and itch that I suffered through. Now, 18 days later, I still have over half the scars, but the itch has lessened tremendously," according to an online reader.
Swimmer's itch is a skin rash that is caused by an allergic reaction to microscopic parasites that are carried by waterfowl, semi-aquatic mammals and snails, according to the Minnesota Department of Natural Resources (DNR). As a part of their life cycle, these parasites are released by infected snails into the water.
This is where they may come in contact with people and burrow into their skin.
There was reportedly a spike in local cases of swimmer's itch right around the first week in July, which is the peak time of year the rash usually hits people; right about the time local lakes are nearly at their warmest summer temperatures.
Ruth Tollefson, a registered nurse with Alexandria Clinic, said because we had a late spring this year, she thought reports of swimmer's itch would have been late, too.
"All of a sudden, bam, we got the calls. It was right on time, right after the July 4th holiday," she said. "We had a lot of vacationers [in the area] calling us; some had never heard of it before."
Swimmer's itch appears as red, itchy, bite-like welts on the skin within several hours of leaving the water. The irritation may last from a few days to several weeks, according to the DNR. About 30 to 40 percent of people who come in contact with the parasite that causes the itch are sensitive and experience irritation.
Tollefson said when a person calls the clinic with what they think might be swimmer's itch, the clinic has a procedure in place.
"We make sure there's no difficulty breathing or confusion... we can't assume their rash is swimmer's itch," she said. "Then, we do an assessment and talk about their possible exposure to swimmer's itch - things like when did the rash start after being in the water."
Then, she said, if it's swimmer's itch, the itchy patients are advised to use over-the-counter remedies like 1 percent hydrocortisone cream or over-the-counter Benadryl.
However, Tollefson advises against using a Bendryl cream in addition to taking an oral Benadryl dose. The cream absorbs into the skin, causing a double dose of Benadryl.
Tollefson said itching should calm down after about three days. If it doesn't, or the rash becomes infected, contact your doctor's office.
HOW TO AVOID SWIMMER'S ITCH
According to University of Minnesota Extension, you can reduce the likelihood of suffering swimmer's itch by following these guidelines:
--Dry off as soon as you leave the water. Rub your skin briskly to remove water drops before they begin to evaporate. Be sure to dry underneath waistbands and around leg openings of swimming suits. Don't sit around in your wet swimsuit. Shower with soap and fresh water as soon as possible after swimming.
--Don't wade or play in shallow water, especially in weedy areas with lots of snails. Swimming from a raft or pontoon minimizes your exposure.
--Clean beaches of weeds or other debris that has washed up on shore, which can harbor the snails that are host to the swimmer's itch parasite. Don't swim when there has been a breeze blowing toward shore that may have carried parasites to your beach.
--Don't feed geese and ducks or allow them to congregate near your beach. Waterfowl are an important adult host for the parasites, and swimmer's itch outbreaks seem to be associated with people feeding ducks.
Lakeshore owners can go one step further. A permit can be obtained from your DNR regional fisheries office to use copper sulfate to kill the snails that are an intermediate host of the swimmer's itch parasite. The copper sulfate will only kill the snails present at the time of application. Any snails that enter the area afterwards will not be affected. The relief provided may be temporary and more than one treatment may be required. Usually only a small percent of the snails in a lake carry the infection, and they may not be the ones around your dock.
HOW TO CONTROL SWIMMER'S ITCH:
A permit can be obtained from your DNR regional fisheries office to use copper sulfate to kill the snails that are an intermediate host of the swimmer's itch parasite. The copper sulfate will only kill the snails present at the time of application. Any snails that enter the area afterwards will not be affected. The relief provided may be temporary and more than one treatment may be required. Usually only a small percent of the snails in a lake carry the infection, and they may not be the ones around your dock. Source: MN DNR
Advice from local nurse: First, call your clinic to make sure it's swimmer's itch you're dealing with. If it is, try over-the-counter products, like hydrocortisone cream, before seeing a doctor.