I've never had to deal with these myself, so I'm not 100% on whether its harmful or not, but a search indicates that they aren't very harmfuI. I remember users on here and dendroboard using panacur to get rid of worms. I looked around, and it appears to be frog safe. There's a liquid and a powder version. I dont know if it'll be hard to find in China. I hope this helps, good luck!