Yes, it is something that other people ( including myself ) have been affected by after longer soaks at DCHS, more prevalent in certain hot pools. It is caused by a natural organism that lives in the water,
https://medlineplus.gov/ency/article/001460.htm , and is mostly experienced in the cooler months/winter when people soak for longer times. And from my experience it seems to be worse after rainfall when runoff bring organic material into the pool, which seems to me may make the organism proliferate, or more active because they might feed on the material, my theory anyway
I have had it a few times where I could not sleep for some hours later at night because of the itching. Thankfully it is usually not a prolonged problem and goes away within 1-2 days for most folks. People have offered up various " ideas " on how to prevent having it occur, but I don't think any of those " remedies " really work. Some people are more affected by the organism than others, just like some folks react differently to Poison Oak. One thing nice about the warmer months at the springs, people mostly do not spend near as much time in the hot pools, and not at all in the summer when the creek is the place to be
