I'm not sure if this is the right place to post this question but someone just brought up a question on my local chicken group about mixing vaccinated and non vaccinated chickens. They said they thought the marek's vaccinated chicks were carrying the virus and could pass it on to the non vaccinated chickens. Is this true? It doesn't sound correct to me. Also, another person said they bought chicks that were supposedly vaccinated but one died and she had a necropsy done and it was riddled with marek's. She was thinking it was not vaccinated and she was lied to but I was thinking a vaccination may not always work. Anyone have any ideas on either of these issues?