Understanding and preventing swimmer's itch

 (Credit: © haveseen - stock.adobe.com)

(Credit: © haveseen - stock.adobe.com)

Have you ever gone swimming in a lake only to break out a few hours later with itchy bumps all over your legs and toes? That's swimmer's itch, and it can really ruin beach trips the same way mosquitos mess up camping trips.

Here's what you need to know to protect your skin (and sanity) from those dreaded itchy bumps. 

It's caused by parasites

Cercarial dermatitis, the technical name for swimmer's itch, is actually an allergic reaction to some microscopic parasites. 

These parasites live in birds, like ducks and geese, and the parasite's eggs enter the water through a bird's feces. (Yuck!)

From there, the eggs hatch and larvae find a new host: snails. The parasites eventually seek a more suitable host in birds, completing the life cycle. However, the microscopic critters occasionally get lost and accidentally burrow into an unsuspecting human.

People aren't suitable hosts, so the parasites quickly die and leave humans with the itchy rash we know as swimmer's itch. The bumps are generally harmless and will heal in a few days. Just try not to scratch too much. If you create an open wound, that could get infected and cause bigger issues. 

It's not chiggers

Swimmer's itch is often incorrectly referred to as chiggers. However, chiggers are tiny earthbound mites that live amidst grass and weeds. They also cause itchy bumps on your skin.  

The parasite that causes swimmer's itch is actually a tiny worm. 

You can read more about chiggers here and swimmer's itch here

You can prevent it

It can be difficult to tell if an area is infected with swimmer's itch. Because the parasite's life cycle is so short, a clear area can become infected quickly and vice versa. However, there are things you can do to reduce your risk. 

The parasites live in shallow areas, so one easy way to avoid infection is to go out to deeper waters. Bring a life jacket if you're not a strong swimmer. 

If you are swimming or wading in shallow waters, avoid marshy areas and rinse off in the shower when you get out. You can wash away the parasites before they have a chance to get into your skin. 

Mayo Clinic also suggests wearing plenty of water resistant sunscreen to protect your skin from the parasites (and UV rays, of course). 

Midwest Clinic