Clinical
Features |
In humans, fever, chills, headache,
muscle aches, and a dry cough. Pneumonia is often evident
on chest x-ray. |
Etiologic
Agent |
Chlamydia psittaci, a bacterium
|
Incidence |
Since 1996, fewer than 50 confirmed
cases were reported in the United States each year. Many more
cases may occur that are not correctly diagnosed or reported. |
Sequelae |
Endocarditis, hepatitis, and neurologic
complications may occasionally occur. Severe pneumonia requiring
intensive-care support may also occur. Fatal cases have been
reported. |
Transmission |
Infection is acquired by inhaling
dried secretions from infected birds. The incubation period
is 5 to 19 days. Although all birds are susceptible, pet birds
(parrots, parakeets, macaws, and cockatiels) and poultry (turkeys
and ducks) are most frequently involved in transmission to
humans. |
Risk
Groups |
Bird owners, pet shop employees,
and veterinarians. Outbreaks of psittacosis in poultry processing
plants have been reported. |
Surveillance |
Psittacosis is a reportable condition
in most states. |
Trends |
Annual incidence varies considerably
because of periodic outbreaks. A decline in reported cases
since 1988 may be the result of improved diagnostic tests
that distinguish C.psittaci from more common C.
pneumoniae infections. |
Challenges |
Diagnosis of psittacosis can be
difficult. Antibiotic treatment may prevent an antibody response,
thus limiting diagnosis by serologic methods. Infected birds
are often asymptomatic. Tracebacks of infected birds to distributors
and breeders often is not possible because of limited regulation
of the pet bird industry. |
Opportunities |
Characterize new and rapid diagnostic
tests for human and avian psittacosis, and determine value
of screening flocks for avian psittacosis to prevent human
infection. |
|
December 2003
|