SubscribeSwimmers itch has been in the news a lot lately in the Alameda area because there have been confirmed cases of the nuisance. It is a flat worm parasite transmitted by an exotic marine snail that is referred to as an invasive species that was probably imported through a ship’s ballast. Fortunately the parasites die as soon as they enter the human body. The parasites are transmitted around the bay area by birds that eat snails and than fly around. Sea gulls are the most common birds that eat in the shallow tide pools where the snails are prevalent but the CDC study did not find the parasites in the birds they collected in the estuary around the Oakland airport.
Here are some facts for the swimmers out there who are planning on swimming off Crown Beach in Alameda. The cecariae parasites usually emerge at temperatures greater than 22 C or 72 F. The Alameda water temperature is usually between 8 C and 20 C (46-68) year round. The tide pools are the most common areas where the temperature goes above 22 degrees. There is also a lot of standing water that gets pretty warm during low tide on sunny days.
The swimmers itch is unique to the San Francisco Bay in Alameda as it rarely occurs in salt water or cold water. The original article that brought all of this to the news is from the CDC Emerging Infectious Diseases division.
FAQs can be found here on the CDC web site.
I really like swimming in the bay but I rarely swim in Alameda. I don’t like the way the water feels, it is not deep enough nor does it move quickly enough. There is also something about the solitude of swimming in the bay right in the middle of a tourist area. The Alameda side of the bay is probably safe for swimmers who jump right in and swim out and back then rinse off as soon as they finish their swim.
If you do get swimmers itch, take a picture and contact the CDC. They need all of the information they can get to help prevent this Emerging problem from spreading.
