Yes you can buy the vaccine and administer it yourself. I was told that some feed stores will carry it, but you can also order it online. My birds have never shown signs of Mareks and I've raised many chicks with them. I did read that it's pretty common, but I truely don't think my flock has it yet so I'm worried that if they are exposed to a bird who does have it at a show, they will get sick and spread it to the rest of my flock. Thanks for the answer, I'll probably vaccinate the whole flcok sometime in June to be on the safe side.