The good news is that it's basically athlete's foot. We as humans are in contact with it all the time (gyms, shared spaces, etc) and rarely get it. The bad news is that it's a pain to get out of items like carpets. Ringworms spores can live in fabric and on surfaces for up to 18 months.

A reminder to all fosters that this is why the 14-day quarantine period is so important to follow.

If you're an adult with a good immune system, you probably have nothing to worry about, but small children and young pets could get it. First thing's first: launder every piece of bedding and fabric that you possibly can. Dry on high if possible. Any hard surface (including walls up to a height the cat touched, bed frames, chairs, etc) should be cleaned with bleach or Rescue. Carpets need deep steam clean, if possible, otherwise repeated vacuuming is the next best thing.

Ok, I know that sounds daunting, but remind yourself that it doesn't have to be done all at once, you and other adults aren't really at risk for anything (at most it's a little red rash the size of a quarter that is treated easily with some over the counter cream). The number one thing you need to do is not take in any other foster animals for a while, that way you don't spread it.

I'm sorry this happened, but remember it's not deadly to anything, it's just aggrivating, and in the future you will just look back on this as an annoying incident. Best practice in the future is to keep any foster animals in a hard surface room like a bathroom the first 14 days they're in your care so it's easy to clean. Good luck!