Recent Increase in Incidence of Chlamydiosis (Psittacosis) in Psittacine Birds in Texas

Chlamydiosis (psittacosis or ornithosis), caused by Chlamydia psittaci, is a disease of psittacine birds as well as domestic poultry, pigeons, and various other species of free-living birds. The disease is a public-health hazard since it is transmissible to man. The disease in man results from close contact with infected birds which are excreting large numbers of chlamydial organisms in their feces. Important sources of human infections have been pet birds, especially psittacine birds. This report describes the diagnosis in recent months of chlamydial infection in an increasing number of clinically ill psittacine birds.