Chlamydiosis Flashcards
Structure
gram-negative, obligate intracellular coccobacilli bacteria, no peptidoglycan cell wall
Species of most concern
C. psittaci, C. abortus, C. pecorum, C. caviae, C. felis
Is it zoonotic?
C. psittaci, C. abortus, C. felis
What type of developmental cycle does it have?
biphasic
Animal reservoirs
C. psittaci: pigeons, parrots, domestic fowl
C. abortus: sheep, goats, pigs, cattle, wild ruminants
C. pecorum: sheep, goats, pigs, cattle, wild ruminants, wild boars, koala
C. caviae: guinea pigs
C. felis: domestic and wild felids
Transmission methods
fecal-oral, inhalation
C. abortus: direct contact with aborted fetuses or placental tissues
C. pecorum and C. caviae: veneral transmission possible
C. felis: direct contact with ocular secretions
Transmission cycle
respiratory droplets or feces contain elementary bodies-> particles dry out-> inhalation from airborne particles
can last for months in environment if particles protected by debris
Pathogenesis
inhaled/ingested-> elementary bodies attach to mucosal epithelial cells-> taken in by endocytosis-> inhibit phagosome-lysosome fusion-> differentiate into metabolically active, noninfectious reticulate bodies-> replicate-> form infectious, metabolically inactive elementary bodies-> released by lysis from cells-> reverse endocytosis also possible escape route-> infect new cells in same area or can disseminate into new tissues
Incubation
C. psittaci: 5-14 days
C. pecorum: 6-30 days
C. Caviae: 5-15 days
C. felis: 3-10 days
Mortality
C. psittaci: in turkeys >30% depending on variant
C. abortus: 25-60% abortion rate in naive herds
C. percorum: Koala mortality ~34%
Clinical Signs in C. psittaci, caviae, and felis
nasal/ocular discharge, conjunctivitis, green/yellow droppings (birds), fever, lethargy, inappentence, weight loss, reduced egg production (birds), abortion (guinea pigs)
Clinical Signs in C. pecorum
Koalas: ocular/nasal discharge, brown colored urine, keratoconjunctivitis
Clinical Signs in C. abortus
Ruminants: late term abortions/stillbirths, keratoconjunctivitis, polyarthritis, coughing, lethargy, fever, inflammation of testicles
Pathologic Lesions in birds
serofibrinous inflammation on serosa, hepatic necrosis, hepato- and splenomegaly
Pathologic Lesions ruminants
-purulent to necrotizing placentitis
-focal necrosis in liver, lung, spleen, lymph nodes and brain in fetus
-fibrinous inflammation on serosa
-thrombosis and malacia in cerebellum and brainstem in calves
Pathologic Lesions in Koalas
-inflammatory infiltrates throughout female reproductive tract
-pyogranulomatous inflammation in kidneys, prostate, and lungs
Pathologic Lesions in Cats
small foci of broncho-interstitial pneumonia
Diagnostics
-not one specific test enough confirmation of disease
PCR, ELISA, Histology, Culture
Treatment
Antibiotics: tetracyclines, macrolides, and fluoroquinolones
Management
vaccination in koalas, cats, and ruminants
Disease reporting
“Closed Herd”
Proper cleaning protocols to prevent spread in domestic species
Limited contact between domestic and wild species
