I'm getting a show quality pair of bantam chickens from a very well known breeder, however, he told me that he had a problem with mareks disease in his LF flocks in the past, so now he vaccinates all of his birds. If I understand correctly, the vaccine won't make them carriers, but it could hide the disease. So if the birds are infected, they will show no symptoms but remains carriers for life. I've raised chickens for 6 years and I've never had any problems with disease. My flock is very healthy and I've never vaccinated them before. So, what risk am I taking? Should I buy the vaccine and vaccinate all of my current birds (young and old) before getting this pair? Is my understanding of how the vaccine works correct? Any help would be much appreciated. Edited to add: Questions about Laryngotracheitis start in post #6. Original question: The breeder also vaccinates for Laryngo as a preventative. Is there anything that I should be aware of with that vaccine? I tried researching it, but I just ended up with a lot of conflicting information. Additional question after research: If the breeder used the chicken embryo origin (CEO) version of the vaccine, will the birds remain carriers possibly spreading the disease to my flock? How about the tissue culture origin (TCO) version?