Chlamydiosis

Question 1

Structure

Answer 1

gram-negative, obligate intracellular coccobacilli bacteria, no peptidoglycan cell wall

Question 2

Species of most concern

Answer 2

C. psittaci, C. abortus, C. pecorum, C. caviae, C. felis

Question 3

Is it zoonotic?

Answer 3

C. psittaci, C. abortus, C. felis

Question 4

What type of developmental cycle does it have?

Answer 4

biphasic

Question 5

Animal reservoirs

Answer 5

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

Question 6

Transmission methods

Answer 6

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

Question 7

Transmission cycle

Answer 7

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

Question 8

Pathogenesis

Answer 8

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

Question 9

Incubation

Answer 9

C. psittaci: 5-14 days
C. pecorum: 6-30 days
C. Caviae: 5-15 days
C. felis: 3-10 days

Question 10

Mortality

Answer 10

C. psittaci: in turkeys >30% depending on variant
C. abortus: 25-60% abortion rate in naive herds
C. percorum: Koala mortality ~34%

Question 11

Clinical Signs in C. psittaci, caviae, and felis

Answer 11

nasal/ocular discharge, conjunctivitis, green/yellow droppings (birds), fever, lethargy, inappentence, weight loss, reduced egg production (birds), abortion (guinea pigs)

Question 12

Clinical Signs in C. pecorum

Answer 12

Koalas: ocular/nasal discharge, brown colored urine, keratoconjunctivitis

Question 13

Clinical Signs in C. abortus

Answer 13

Ruminants: late term abortions/stillbirths, keratoconjunctivitis, polyarthritis, coughing, lethargy, fever, inflammation of testicles

Question 14

Pathologic Lesions in birds

Answer 14

serofibrinous inflammation on serosa, hepatic necrosis, hepato- and splenomegaly

Question 15

Pathologic Lesions ruminants

Answer 15

-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

Question 16

Pathologic Lesions in Koalas

Answer 16

-inflammatory infiltrates throughout female reproductive tract
-pyogranulomatous inflammation in kidneys, prostate, and lungs

Question 17

Pathologic Lesions in Cats

Answer 17

small foci of broncho-interstitial pneumonia

Question 18

Diagnostics

Answer 18

-not one specific test enough confirmation of disease
PCR, ELISA, Histology, Culture

Question 19

Treatment

Answer 19

Antibiotics: tetracyclines, macrolides, and fluoroquinolones

Question 20

Management

Answer 20

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