Transmission of classical Marek's disease by affected and carrier birds.
D000818:Animals; D001353:Avian Leukosis / Q000175:diagnosis / Q000382:microbiology*; D001354:Avian Leukosis Virus / Q000302:isolation & purification*; D001715:Bird Diseases / Q000382:microbiology*; D002353:Carrier State / Q000382:microbiology / Q000662:veterinary*; D002645:Chickens; D011201:Poultry Diseases / Q000382:microbiology*