New Puppy...Is he sick?

Question
I just bought a new Chihuahua puppy and he's about 7-8 weeks old. We've just noticed small sores on his underbelly that we are worried about. I have 2 small children including one 2 year old that has been inseparable from him and I need to know whether or not I need to worry about the dog's health or her's. Please let me know if this sounds dangerous or just a simple dog issue. The dog hasn't been near or in anything new. One or two of the sores seem to have busted and they have stuff coming out of them. They also seem to be in places where his skin touches. For example: He has a sore on his knee and the exact place on his belly that rubs against his knee when he sits. This leads me to believe it's spreading or contagious. Please help!

Answer
Sounds like a staph infection to me. Take him to the vet. :) He'll put him on antibiotics, possibly oral ones definitely ointment. Keep him very clean and dry while waiting to take him in for his appointment. Staph can be  contagious so have your children refrain from handling him until he sees the vet and make sure they wash hands etc if they DO handle him. You should do so yourself, particularly be cautious of open wounds. Get him in as soon as you can to keep it from getting worse, and again keep the areas very clean and dry. If he won't lick the areas using some triple antibiotic ointment is a good idea until you can get him in, at least a couple of times per day.
Good luck :)
Cindi