Unit 4 - Spirochaetaceae and Leptospira Flashcards
What is the shape of organisms in the order Spirochaetales?
flexous, helically coiled, spiral organisms
What are the two families of importance in the order Spirochaetales?
Leptospiraceae and Spirochaetaceae
Leptospiraceae and Spirochaetaceae are collectively referred to as __________.
spirochetes
What are spirochetes made up of (their parts)?
protoplasmic cylinder, cell wall, periplasmic flagella, and outer sheath
What is the protoplasmic cylinder composed of?
the cytoplasm and the cytoplasmic membrane of the organism
What surrounds the protoplasmic cylinder in spirochetes?
the cell wall
One to one hundred _______ are present on all spirochetes.
flagella
What are the flagella of the spirochetes connected to and what is the attachment site called?
the protoplasmic cylinder - the basal insertion plate or disc
True or False: If there were to be a cross section at the middle of a spirochete there would be two times as many flagella than at the end.
TRUE
What does viscotaxis mean?
the ability to move through rather viscid substrates such as 1% agar and intestinal mucus
What is found in the outer sheath of spirochetes?
LPS
True or False: The flagella are contained outside of the outer sheath of spirochetes
FALSE
Are sprirochetes gram negative or positive?
negative - but they do not stain well with the gram stain
What is the basic taxonomic unit of the genus Leptospira?
serovar - the serovar name is capitalized
What are the common serovars of Leptospira interrogans?
Icterohemorrhagiae, Canicola, Pomona, Autumnalis, and Bratislava
What are the common serovars of Leptospira noguchii?
Pomona
What are the common serovars of Leptospira borgpetersenii?
Hardjo
What are the common serovars of Leptospira kirschneri?
Grippotyphosa
What is the morphology of Leptospires.
they are motile, spiral rods with one or both ends hooked
What is the outermembrane of Leptospira covered by?
a slime
What is the best way to visualize Leptospira?
with darkfield microscopy
What conditions, in regards to oxygen, does Leptospira prefer?
microaerophilic conditions
What does Leptospira utilize for carbon and energy services?
long chain fatty acids and alcohols
What is typically added to media to bind Leptospira to serum or albumin?
Vitamin B1 or B12
What can Leptospira utilize as nitrogen sources?
ammonium salts
What virulence factors does Leptospira have?
viscotaxis and cytotoxin
Where is Leptospira most commonly found?
in hot and humid climates
What is the natural habitat for most serovars of Leptospira?
the proximal convoluted tubule
How is Leptospira transmitted?
by direct contact with urine or indirectly through urinary contamination of food, water, or soil
In the environment, especially moist and warm ones, what can Leptospira survive in?
ponds and other small bodies of water
What is the most common route of entry of Leptospira?
through penetration of mucous membranes of the eyes, mouth, nose, genitalia, or abraded skin - possibly through water-softened intact skin
True or False: Venereal transmission of Leptospira is possible.
TRUE
What is the pathogenesis of leptospirosis largely dependent on?
whether an animal host is a maintenance host or an incidental host
What is the difference between maintenance hosts and incidental hosts of Leptospira?
maintenance hosts often do not become clinically ill or are only minimally ill whereas incidental hosts can develop a high fever and become acutely ill
Where does primary multiplication of leptospires occur and what is the duration of this event?
in the liver - 4-7 days
Post infection, where do leptospira localize?
the kidney, brain, lung, and possibly other tissues where antibody does not have ready access
Which hosts are responsible for long-term shedding and the maintenance of leptospirosis in a population?
the maintenance host
In incidental hosts, how does leptospira manifest as?
vascular damage, hepatitis with jaundice, acute nephritis followed by chornic nephritis, abortions, and meningitis
How can Leptospira cause abortion?
it enters the placenta through maternal circulation and migrates to the fetus
Abortion usually occurs when the animal is infected with Leptospira in what trimester?
the third
What Leptospira serovar are rats reservoir hosts of?
Icterohaemorrhagiae
What Leptospira serovar are dogs reservoir hosts of?
Canicola
What Leptospira serovar are raccoons reservoir hosts of?
Grippotyphosa
What Leptospira serovar are cattle reservoir hosts of?
Hardjo
What Leptospira serovar are swine reservoir hosts of?
Pomona
What clinical signs/syndromes does Leptospira cause in cattle?
abortion, still births, weak calves, low fertility syndrome, milk drop syndrome, hemolytic anemia, icterus, and hemoglobinuria
What common serovars cause bovine leptospirosis?
Hardjo-bovis, Pomona, Grippotyphosa, and Icterohaemorrhagiae
What species is swine leptospirosis’ clinical manifestation similar to?
bovine
What common serovars are associated with swine leptospirosis?
Pomona, Grippotyphosa, Icterohaemorrhagiae, and possibly Bratislava
If sheep get leptospirosis, what clinical syndrome/lesions are associated with it?
abortions and occasionally hemolytic anemia
What Leptospira serovars are common in sheep?
Pomona
What Leptospira serovars are common in goats?
Pomona, Icterohemorrhagiae, and grippotyphosa
What clinical signs/syndromes are associated with leptospirosis in horses?
abortions, still births, weak foals, periodic opthalmia (moon blindness)
What Leptospira serovars are associated with equine leptospirosis?
Pomona
What percentage of horses develop anterior uveitis if infected with Leptospira?
fifty percent
What clinical signs/syndromes does Leptospira cause in dogs?
acute hepatitis, acute/chronic nephritis, meningitis, and pulmonary vasculitis
What Leptospira serovars have historically been the most common cause of disease in dogs?
Canicola and Icterohaemorrhagiae
What species appear to not be susceptible to leptospirosis?
cats and birds
In humans, leptospirosis is an _________ hazard.
occupational
What clinical signs/syndromes are associated with human leptospirosis?
fever, chills, headache, aching muscles, icterus, and stiff neck, respiratory distress due to pulmonary hemorrhage, nausea and vomiting, anuria, rashes, conjunctivitis, meningeal irritation, and hepatic or renal failure in severe cases
How do you diagnose leptospirosis?
Microscopic agglutination test (MAT), PCR, ELISA, Culture, darkfield, silver staining, and flourescent antibody test
How long do leptospira cultures need to be incubated to identify the infecting serovar?
18-24 days
What do bacterins for leptospirosis protect against?
clinical disease but not against infection
Post-immunization or post-infection immunity is primarily ______ mediated and protection is generally ____-lived.
humorally, short
How is leptospirosis treated?
ampicillin or penicillin to kill systemic organisms followed by tetracycline or doxycycline to kill the remaining population
