Bacte Lec: Leptospira Flashcards
Leptospira characteristics
● Aerobic
● Gram-negative
● right-handed flexible helical rods with more than 18 coils per cell
● Each organism is hooked at one or both ends
● They are motile by two subterminal periplasmic flagella
● They use long-chain fatty acids and alcohols as energy and carbon sources
Are leptospira motile?
They are motile by two subterminal periplasmic flagella
What is leptospira’s source of energy and carbon sources?
They use long-chain fatty acids and alcohols as energy and carbon sources
What are the taxonomic systems for Leptospira?
molecular taxonomic & traditional approach
Taxonomy system that uses DNA-DNA hybridization
Molecular taxonomic approach
Taxonomy system that is a serologic system based on antigenic differences.
Traditional approach
Leptospira that composed of the pathogenic or parasitic serovars
Leptospira interrogans
How many serovars L. interrogans?
218
Leptospira containing the free living leptospires
Leptospira biflexa
How many serovars does Leptospira biflexa have?
60
This test is widely used to detect antibodies of Lepstospira and is highly serovar specific.
Microscopic agglutination test
This is used in identification of serovars after isolation and cultivation
Serologic procedures
In leptospira it primary disease of animals but can be transmitted to humans directly or indirectly
Leptospirosis
Leptospirosis natural host:
rodents, swine, dogs
Leptospirosis source of infection?
Source of infection is urine from infected or carrier animal; Water, litter, food may serve as fomites
T/F: Leptospira live in alkaline water for days.
True
Transmission of leptospira is by?
Direct or indirect infection via nasal, oral or conjunctival mucous membrane and abraded skin
T/F: Leptospires cannot be destroyed in the stomach.
False: Leptospires destroyed in the stomach
T/F: Virulent strains produce more cytotoxic proteins than avirulent ones
True
It is responsible for intravascular hemolysis.
Hemolysin
What are the other virulence factors of leptospira?
Other virulence factors: motility, burrowing motility, production of hyaluronidase
Where does leptospira localize and proliferate?
Parenchymatous organs (kidney & liver)
Where does Leptospira multiply?
Multiplication in convulated tubules.
T/F: In carrier state, organisms shed in urine for days only.
False: organisms shed in urine for weeks or months
Leptospira clinical signs
fever, anemia, subserous and submucosal hemorrhages, conjunctivitis, icterus, meningitis and agalactia
Death occurs in what stage?
febrile stage or later
Death in Leptospira is caused by?
Toxemia resulting from kidney and liver damage primarily humoral
Canine Leptospirosis is caused by?
Leptospira interrogans serovar canicola
It is primarily caused by serovar canicola, less frequently by icterohemorrhagiae
Canine Leptospirosis
In canine leptospirosis, how long do dogs and rats shed leptospires in urine?
Dogs shed leptospires in their urine for 2-6 months, rats for longer periods
Four principal forms of Canine Leptospirosis.
(1) Hemorrhagic form (icterohemorrhagiae)
(2) Icteric form (icterohemorrhagiae)
(3) Uremic or subacute form (canicola)
(4) Inapparent form (canicola)
The first 3 principal forms of Canine Leptospirosis are characterized by
depression, anorexia, vomiting, diarrhea or constipation
What causes severe leptospirosis in dogs?
Grippotyphosa
In dark field microscopy, what compound is added to prolong the specimen?
Formalin
In what animal is Leptospira interrogans serovar canicola inoculated?
Guinea pig or hamster inoculation; blood, urine, tissue used
Causes bovine leptospirosis
Leptospira interrogans serovar pomona
Serovar ____ some regions; it causes fewer abortions than serovar ____ but results more often in infertility.
(1) hardjo; (2) pomona
Animal sources of Bovine leptospirosis
Cattle and swine and some wild animals
Bovine Leptospirosis outbreaks is due to frequent what?
Outbreaks associated with heavy rainfall but infrequent under dry conditions
Clinical signs of bovine leptospirosis
Infections characterized by fever, diarrhea, anemia, icterus and hemoglobinuria; acute infections may result to abortion
Porcine Leptospirosis is caused by?
Leptospira interrogans serovar pomona
T/F: Bratislava extremely difficult to culture
True
Sources of porcine leptospirosis
swine, cattle, skunks, raccoons, opossums, wildcats, and deer
Clinical signs of Porcine leptospirosis
Unthriftiness, abortion, fever, icterus and anemia; Occasionally, metritis and meningoencephalitis
It causes equine leptospirosis
Leptospira interrogans serovar pomona
Equine leptospira clinical signs
usually mild or subacute with fever, depression and icterus, occasionally abortion and uveitis
T/F: Equine leptospirosis systemic disease is common.
False: systemic disease is rare
T/F: Equine leptospirosis is mainly humoral.
True
In equine leptospirosis’ immunity it elicits considerable protection.
Bacterins
T/F: Bacterins are effective in horses.
False: Bacterins not available for horses
Serovars found in dogs
canicola and icterohemorrhagiae
Serovars found in cattle
pomona, hardjo, grippotyphosa, canicola, icterohemorrhagiae
Serovars found in swine
pomona and bratislava
Leptospira is known for disease conditions of
Well’s disease, Fort Bragg Fever and Swineherd’s disease
