Losses are greatest in very young birds but can be seen at almost any age. Survivors of these infections remain carriers for life and can become a source of infection for other birds. Breeders produce hatching eggs which contain these bacteria and chicks are hatched with the infection and frequently die.
Pullorum disease will affect turkeys, ducks, guinea fowl, pheasants, sparrows, quail, bittern, geese, pigeons, doves, parakeets and canaries.
The infection may spread by breathing contaminated dust or coming into contact with down from infected poultry or with other material in the incubator, shipping box, brooder, or pen that has been touched by an infected bird.
Blood-testing adult breeding birds in combination with biosecurity and sanitation have all but eliminated the disease in the United States.