Swimmers Itch
One area of interest to homeowners on the lake is Swimmers Itch (SI) and the Swan Lake Association wants to be a resource for this issue as well. Our President Ron Guggisberg has agreed to be the point person for the issue.
Swimmer’s Itch is not a problem early in the year until the water warms up.
In 2019 that happened around July 4th. In 2020 that occurred about in the middle of June.
Preventing Swimmer's Itch
The ‘Tip of the Mitt’ Watershed Council had a great page on what Swimmer’s Itch (SI) is, and how to prevent it. Here is the link, and below are some recommendations to significantly reduce your chance of contracting it. https://www.watershedcouncil.org/swimmers-itch.html
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SI is not a bite. It is your body’s allergic reaction to the larvae. That is why the severity varies among people.
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Since itch-causing larvae usually live in the shallows near the shore, it is best to avoid these areas as much as possible. This is especially important when the wind is blowing toward the shore.
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Swim off the end of the dock or out in the middle of the lake.
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Shower and/or towel off thoroughly as soon as you leave the water to rub off the larvae before it fully penetrates the skin. You can be in the water all day… the problem starts within 5 minutes or so after you get out as the water evaporates.
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Do not feed waterfowl! Feeding waterfowl may aggravate the problem by concentrating potential hosts in a limited area. I used to think that Mergansers were the culprit duck because that is what researchers in Michigan have discovered. However, they also state that the carrier may vary from one location to the next.
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Pick up all of the snails in shallow water. The larvae only live for 24 hours.
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Before entering the water, be sure to lather up your legs with waterproof sunscreen, baby oil, Vaseline, or ‘Swimmers Itch Guard’. This will prevent the larvae from penetrating your skin.
If you get Swimmer's Itch
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Try to keep it cool.
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Don’t scratch… yeah right!
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Hydrocortisone spray works well… no rubbing.
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Benadryl Extra Strength Anti-Itch cream works better than the gel.
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Benadryl tablets can help you sleep.
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If you soak with baking soda or Epsom salt… use cold water.
Copper Sulfate (CS)
I have treated with CS (yes, I did get a permit from the DNR). Treatment with CS is not always effective. I have treated and STILL gotten SI! Besides that, Copper Sulfate is not good for the health of the lake, and it is very expensive. If you decide to treat with CS I would offer the following suggestions:
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DO NOT use the often-recommended method of putting CS in a gunny sack and dragging it through the water, especially if your CS is in the small granular form (like sugar). That method may work in much coarser format, but the finer granules will run right through the gunny sack!
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Just because it comes in a 50-pound bag does not mean you should use it all! That is FAR too much for one application for the average homeowner’s beach area. Most beaches should require no more than 10 pounds. There is a formula for figuring out the amount to use.
Take the time to go through it. -
Copper Sulfate does not kill the larvae… it kills the snails that carry the larvae.
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As the snails die, they give up any larvae that they are carrying. The WORST time to swim is the day you treat. Best to swim 36 to 48 hours after treatment.
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Other Useful Sites
https://www.dnr.state.mn.us/swimming/swimmersitch.html
https://www.lakemissionviejo.org/119/Swimmers-Itch
https://healthh.com/swimmers-itch/
Send me an email with your SI experiences so we can all learn from them. rfguggisberg@gmail.com Some information that we would like to gather is (to the best of your memory):
1. Your name:
2. Your address:
3. Is that where you got SI?
4. Date that you got SI?
5. Did you treat your beach with copper sulphate (or something else)?
6. If so, how long before contacting SI did you treat?
7. How did you apply it?
8. How much did you use?
9. Do you typically see ducks on your beach?
10. Was the wind blowing in or out from shore?
11. What was the air temperature?
12. What was the water temperature (if known)?
Again, I look forward to hearing from you.
Ron Guggisberg