Spirochetes Flashcards
Are spirochetes zoonotic?
yes - many can cause zoonotic infections
Are spirochetes intracellular or extracellular pathogens?
extracellular
Describe the general shape of spirochetes
spiral with endoflagella (motile)
gram negative
Oxygen requirements of leptospira
aerobic
How many periplasmic flagella do leptospira have?
2
How many periplasmic flagella do brachyspira have?
6-10
Oxygen requirements for brachyspira
microaerophilic/anaerobic
How many periplsamic flagella do borrelia have?
15-20
Oxygen requirements of borrelia
microaerophilic
What type of staining is reccomended for leptospira?
does not stain well with gram stain
use Warthin Starry or Giemsa
view under darkfield
How are leptospira classified?
based on species name and serovar
How is leptospira transmitted?
shed in urine, uterine discharges/placental fluids
enter through broken skin and mucous membranes
Virulence factors of leptospira
flagella
hemolysins
adhesins
LPS
Clinical sings of leptospira in dogs
biphasic
leptospiremic phase
leptospiruric phase
acute hemorrhagic disease
uraemic type - kidney damage
ulcerative stomatitis
Clinical presentation of leptospira in cattle
abortion “storms”
infertility
sporatic abortions
milk drop syndrome
hemoglobinuria
jaundice
pyrexia
Clinical presentation of leptospira in pigs
infertility
aabortions
stillbirths
Clinical presentation of leptospira in horses
recurrent iridocyclitis
acute renal failure
abortions
Indirect method of diagnosing leptospira
microscopic agglutination test - gold standard
4-fold increase in antibody titer between acute and convalescent serum samples
ELISA
Direct methods of diagnosing leptospira
PCR
culture - heparinized blood, urine, CSF, kidneys
Culture requirements for leptospira
grow at 30C
require Tween 80, bovine serum albumin, B1 and B12, and 5-fluorouracil
What type of culture medium is used for leptospira?
EMJH
fletcher medium
korthoff
vervoort
noguchi
schuffer
How long does leptospira take to grow in culture?
3 months
Treatment of leptospira in dogs
penicillin G
doxycycline
Treatment of leptospira in horses
penicillin
tetracyclines
aminoglycosides
Treatment of leptospira in livestock
tetraycline
oxytetracycline
erythromycin
tiamulin
tylosin
centiofur - reduce shedding
Which species are there leptospira vaccines available for?
dogs
cattle
pigs
livestock in New Zealand
Prevention and control of leptospira
do not allow pets to drink water from stagnant drains/streams or have contact with reservoirs of infection
Describe the general appearance of Borrelia
longer and wider than other species
helical shape
linear chromsome
linear and circular plasmids
How is Borrelia transmitted?
via arthropod vectors
Is borrelia intracellular or extracellular pathogen?
obligate parasite
What is the causative agent of Lyme disease?
Borrelia burgdorferi
What is the causative agent of avian spirochaetosis?
Borrelia anserina
What is the causative agent of tick spirochaetosis?
Borrelia theileri
Where is Lyme disease endemic?
North America, Europe, Asia
Virulence factors of Borrelia burgdorferi
Osp A
adhere to gut
osp C
resist compliment mediated killing by binding a complement-inactivating component of saliva
Clinical signs of Lyme Disease in dogs
inappetence
fever
polyarthritis
shifting lameness
kidney damage
herat disorders
neurological signs
Clinical signs of Lyme Disease in cats
asymptomatic
inappetence
fever
lameness, stiffness and swelling of joints
difficulty breathing
blindness
Clinical signs of Lyme Disease in cattle
clinically silent
fever, laminitis, a/o weight loss
lameness
skin rash on udder
arthritis
Clincal signs of lyme disease in horses
mild fever
lameness/stiff joints
laminitis
depression
loss of appetite
blindess/partial loss of vision
abortion
neurological signs
encephalitis
Diagnosis of Lyme Disease
IFA
ELISA
giemsa stain, FA, darkfield
PCR
Treatment of Lyme Disease
4 weeks doxycycline/tetracycline
Prevention and control of Lyme Disease
tick control
vaccination
Transmission of borrelia anserina
fowl tick
Distribution of borrelia anserina
tropical and subtropical
sporadic outbreaks
Affected species of borrelia anserina
chickens, ducks, turkeys and geese
Clinical signs of borrelia anserina
fever
depression
cyanosis
greenish diarrhea
later stages: paralysis and anemia
Diagnosis of Borrelia anserina
demonstration of the organism in the buffu coat using darkfield microscopt or immunofluorescence
giemsa or silver stains
isolation in embryonated eggs
PCR
Treatment and control of Borrelia anserina
antibiotics
isolation
tick removal and control
vaccination
Brachyspira general characteristics
anaerobic inestinal bacteria in pigs - can survive in moist feces for about 2 months
How is brachyspira hyodysenteriae transmitted?
fecal-oral route
Vectors of brachysoira hyodysenteriae
dogs
rats
mice
flies
Causative agent of swine dysentery
B. hyodysenteriae
Causative agent of porcine intestinal spirochaetosis
B. pilosicoli
Causative agent of porcine spirochaetal colitis
B. intermedia
Clinical signs of B. hyodysenteriae
weaned pigs 6-12 weeks old
decreased appetite/increased thirst
emaciation/loss of condition
profuse muco-hemorrhagic diarrhea
Virulence factors of B. hyodysenteriae
motility
chemotactic
LPS
hemolysins
NADH oxidase
Pathogenesis of B. hyodysenteriae
colonic goblet cell invasion
hemolysins and cytotoxins
dehydration and acidiosis
Diagnosis of B. hyodysenteriae
darkfield microscopy of abnormal mucosa or fecal swabs
culture
PCR
immunofluorescence
ELISA
Culture of B. hyodysenteriae
blood agar with antibiotics incubated at 42C anerobically
complete hemolysis around colonies
Treatment and control of B. hyodysenteriae
improve sanitation and hygiene
medicate drinking water with tiamulin, linocmycin and nitroimidazoles
alter diet
depopulation
rodent control
vaccination
Disease caused by trponema spp
bovine digital dermatitis
contagious digital dermatitis
rabbit syphilis/vent disease
