Pullorum Epidemiology

The incidence and distribution in Montana and elsewhere, along with the information regarding the spread of the disease.

Blood testing adult breeding birds, biosecurity and sanitation have all but eliminated the disease in the United States.

Transmission

Transmission is primarily through the egg but also occurs by direct or indirect contact. The infection may spread when uninfected poultry breathe contaminated dust or come 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.

Infection transmitted via egg or hatchery usually results in death during the first few days of life and up to 2-3 wk of age. Affected birds huddle near a source of heat, do not eat, appear sleepy, and show whitish fecal pasting around the vent. Survivors frequently become asymptomatic carriers with localized infection of the ovary. Some of the eggs laid by such hens hatch and produce infected progeny.