If you have tried de-fleaing the doggy, try de-fleaing the doggy at the same time as de-fleaing the house.
A trip to the vet may be in order for some advice. Just be prepared to remortgage the house if you actually want to TALK to him.
£10 to open the door
£10 to talk to the receptionist
£5 per butt that takes a seat in the waiting room
....and so it goes on...