Very good! Be on the lookout for bites and scratches, and even squabbles! If you see noticeable wounds, you can go to a local market and get some fresh Thyme, get some hot water in a mug (just enough to cover the sprigs of thyme) and let that steep for about half an hour. It's a really good infection fighter, and all you have to do is make it and dab it on the wound for a total of about 5 minutes, and probably 2 times a day. If you have a health food store near you, Manuka Honey (+18 I think) is really, REALLY good for fighting infections. All you have to do is put a dab on the wound. Even if they lick it off, the hamster will still get the necessary nutrients from it!