My heart is breaking! Last year, I purchased some pullets from my local feed store that did not have proper Marek's vaccinations and they infected my property with the disease. I went through about a half dozen pullets and only have one hen alive from those. This year, I was trying to replenish my flock and I am now on chicken number 3 that was vaccinated and has died from Marek's. I actually had one necropsied and it confirmed that it died from that. I have been buying vaccinated 10 week olds thinking they would have enough time to build up the resistance. Any advice on what I can do? I keep an extremely clean chicken area but know that once you have Marek's, it's almost impossible to get rid of it. My older hens are all still doing fine. FYI, I have been raising chickens for 10 years now.