Sam is 12 years old and this is the first time he has had fleas! Came in from work today Sam greeted me but wasn't himself, rolled over for a belly tickle and I saw all these red things crawling all over him, which I realised were fleas. I've pit advantage flea treatment on him, how long before all these nasty things are gone, and how do I know. Do I have to then bath him. I have also got rid of his bedding can't bear the thought that being infested too. Any suggestions greatly accepted as how to deal with this.