Brucella Flashcards
This disease MAY be caused by:
* Brucella abortus
* Brucella melitensis
* Brucella suis
* Any of the above
All of the above
The risk of the veterinarian becoming infected
and clinically symptomatic with this etiological
agents is:
* Nonexistent
* Low
* High
** Depends on the exact agent
Most likely cause in a dog is brucella canis and is the most common zoonotic pathogen worldwide.
Brucella
–> Morphology
- _______ (0.5-0.7 x 0.6-1.5 μm)
- Usually single cells
- Gram- _____
- Strict _____
don’t care Most are catalase and oxidase +, and urea +
don’t care Non-motile
- Category B Select Agent
BLS-3 required for cell ______ of all
Brucella nomenspecies; BSL-2 for _______ _______.
Coccobacillus, negative, aerobe, culture, infected tissues
Brucella- Composition and Metabolism
* Facultative _______ pathogen
* Aerobe; many strains require increased levels of ___
* Nomenspecies differentiation based on
1. ______ reactivity
2. ____ composition
3. ________ susceptibility
4. ___ specificity
intracellular, CO 2
Biochemical, Antigen, Bacteriophage, DNA
biotypes: biochemical testing shows differences
do not memorize
do not memorize
Other species
* B. opinata
* BO1-U.S. human breast implant
* BO2-Australia man with pneumonia
* Australian rodent strains NF2653 and 86-13
Brucella LPS Antigens
- Which strains of Brucella ar econsidered to be smooth nomenspecies? Which antigen do they express?
- B. abortus expresses which antigen?
- B. melitensis expresses which antigen?
- What is the difference between the antigens B. abortus and B. melitensis express?
- O-antigen involved in _______ reaction and other serological assays
- Closely related to Yersinia enterocolitica O:9, Francisella tularensis, and E. coli O157:H7 antigenically
- B. abortus, B. melitensis, B. neotomae, and B. suis; smooth O-antigen
- Aobrtus LPS = A antigen
- Melatensis = M antigen
- Same sugar, so linked differently making them antigenically different; Linkages of O-antigens differ and can be used to differentiate
B. abortus and B. melitensis - agglutination
- B. canis and B. ovis exhibit ____ LPS, which lacks __-
antigen and has a core oligosaccharide of mannose,
glucose, 2-amino-2,6-dideoxy-D-glucose, glucosamine
and 3-deoxy-D-manno-2-octulosonic acid (KDO)
** FOR ALL NOMENSPECIES: LPS may contribute to _______ survival, but it is NOT a substantial _____
rough, O
Have Lipid A and core. One reason why they are less virulent.
intracellular, endotoxin
**Transmission
–> Reservoir are _____ animals or ____ infected animals
2. What is the most common for of transmission?
3. Another form of transmission is exposure of infected _____ _____ as well as ______ and _______.
–> 4. For the 4 zoonotic pathogens (?), what is the most common form of transmission to humans?
–> ____ infections are cleared in 4-6 weeks, but can persist in the _____ and ______ system (RES) indefinitely for some nomenspecies.
carrier, newly
2. Ingestion of placenta, uterine fluids, milk, urine
3. mucous membranes, venereal, congenital
abortus, melitensis, suis, canis
- handling aborted fetus, placenta, and uterine fluids, or consuming infected milk or cheese is the most common mode of transmission
Genital, udder, reticuloendothelial
Brucella abortus
Initial isolation: Dr. ____ (1897)
Geographic distribution: _____
–> Transmission
1. ____ – primary mode
2. ____ transmission
3. ____-____ and ____ transmission
4. Some cattle are more ____ to infection
Bang, worldwide
1. Ingestion
2. Venereal
3. Intra-mammary, congenital
4. resistant
B. abortus Pathogenesis
* Bacteria penetrate _______ ______
* Localize in regional _____ _____
* Phagocytosis by ______ and fixed ______
* Bacteremia – disseminates to ______, _____, and ____ ______system
* Can also localize to the _____ tract of males
mucous membranes, lymph, nodes, neutrophils, macrophages, udder, uterus, reticulo-endothelial , genital
Orchitis/Epididymitis
B. abortus Pathogenesis
**** Proliferate best in cells with high levels of _____; i.e., ?
***** Concentration of bacteria greatest at time of _____; disappear from
genital tract within ___ days after gestation
* Maintained in _____ Endothelial tissues and udder –> which is why it is shed in the ___
erythritol, Trophoblasts of placenta, abortion, 30, Reticular, milk
What can be seen in this image?
Bovine, placenta. The placenta contains
numerous hemorrhagic cotyledon
What can be seen in this image?
Bovine, placenta. Numerous pale clumps of
exudate are scattered over the cotyledon and
adjacent chorion.
B. abortus Disease
* Placenta may be _______; cotyledons show ___ or _____ areas of necrosis
* ______ may be retained
* Most infected animals remain ______; shed bacteria after _____
thickened, local, diffuse, Placenta, carriers, calving
B. abortus Disease
* Abortion – after ____ month
* Usually only during ___ pregnancy
* <____ % abort more than once
* Fetus _____
* ____ tinged fluid in body cavities
* Turbid ______ contents
5th, first, 20, edematous, Blood, abomasal
B. abortus disease
B. abortus Laboratory Diagnosis
______ disease
Zoonoses
____-may need to send to reference lab or Laboratory Response Network lab with BSL-3 facilities; But ____ is more commonly used today.
What samples would you send to the lab?
___ test can be used and can also differentiate _____
*** Gold standard is _______-based on ____ __-antigen
___ agglutination test – ____ and ___
____ test
Affected by vaccination (strain __), ____ infection, and ____-specific antigenic stimuli
___ or ___ Bengal test (slide-type agglutination assays performed
with a stained B. abortus suspension at pH 3.6–3.7 and serum– test
for ____
_____; very _____
Few false _____
Notifiable, Culture, Culture
Genital secretion, milk, blood; from necropsy- spleen, liver, udder and lymph nodes – can also do gram strain of these tissues
PCR, nomenspecies
SEROLOGY, LPS O, Tube, IgM, IgG1, Screening, 19, ongoing, hetero, Card, Rose, IgM, Rapid, sensitive, negatives
B. abortus Laboratory diagnosis (continued)
–> Rivanol or Mercaptoethanol test
* Used to distinguish between ____ infection and ____
* ___ removed from serum
* Titer decrease indicative of Strain ___ (vaccine) titer
* Chronic infection exhibits higher ____ _ than IgM
–> Complement fixation test do not worry
* More sensitive and specific (Reference laboratory)
* A prescribed test for International trade
chronic, vaccination, IgM, 19, IgG 1
Serological Diagnosis
–> ELISA - can be used in control programs
* Very _____ and ____ (comparable to CFT)
* Test for _____ trade
–> Fluorescence polarization assay (FPA)
* ____ and ____: can be used in laboratory/Field
* ______ labeled >50kD antigen (~22 kD O-antigen)
* Mixed with blood/dilute serum read in 2 minutes using a polarization analyzer
* Calibration of test with OIE/USDA standards
sensitive, specific, International, Simple, sensitive, Fluorescein
B. abortus Immunology
–> ______ antibody response does not correlate
with protection
Antibodies may act as ____ antibodies and prevent
complement-mediated ____
May enhance cellular uptake as ______
–> ___ mediated immunity is the principal protective
immune response
Sensitized T cells release _____ that activate
macrophages, which are better able to ___ the bacteria
Following infection, animals are_______
–> Causes ______ lesions
Humoral, blocking, lysis, opsonins, Cell, cytokines, kill, protected, granulomatous
B. abortus Vaccination - Strain RB51
* Attenuated, viable strain; no LPS O-antigen
* Conditional license 1996
* Formal License 2003
* Federal recommendation
* Vaccinate __-___ months of age
* ____ vaccination off-label; need data of long-term studies
* Do not vaccinate ____ animals
* Protects ___-___% of vaccinated animals
* Can use the vaccine to interrupt _____
* Readily differentiate vaccinated animals from infected animals due to differences in titer to ?
4-12, Adult, pregnant, 85-90, outbreaks, LPS O-antigen
B. abortus Vaccination - Strain 19
* Viable ______ strain; ______ pathogenic; ____
* Federal recommendation
* Vaccinate 4-12 months of age
* Avoids development of persistent agglutinins
* Previous vaccine used in eradication
* Protects 65-70%
* Latent infected animals do not benefit from
vaccination
* Can cause abortion
smooth, mildly, stable
B. abortus Vaccine - McEwen 45/20
* Inactivated, adjuvanated rough strain
* Required 2 initial doses 6-12 weeks apart
* Booster at 12-18 months
* Used in Ireland and parts of Europe
DO NOT STUDY
B. abortus
Control and Eradication
Based on:
Test and ____
Vaccinate all _____ animals
Enhance principals of _____
Brucella Ab milk ____ test ( ____ basis, but high false ___)
Still a major problem is Brucella in ___ and ___ in Yellowstone area
slaughter, replacement, hygiene, ring, herd, +, Elk, Bison
B. abortus Therapy
* Not attempted in ___ and _____
* Tetracycline and streptomycin or gentamicin recommended
in ____ and ___ and _____
* Therapy needs to be ____-term and _____ are common
* ______ infection – difficult to eliminate
* ____ infected animals and vaccinate new ones
* U.S. Brucella-free in 2008, but occasional infections occur in _____ states
pigs, ruminants, Rams, dogs, humans, long, failures, Intracellular, Cull, Western
B. melitensis
* First Brucella species isolated: Dr. ____ (1887);
spleen of human on Island of ___ (_____ fever)
* Geographic distribution: Southwestern U.S., Mexico,
Central America, Southern Europe, Africa
* BSL-3 Category B select Bio-Warfare agent
* No human vaccines & 10 to 100 cfu infectious dose
by aerosol
Bruce, Malta, Malta
B. melitensis: Transmission
*primarily by ______
* Sources: ?
* Food and water contaminated by ____ and ____ discharges
* Milk and cheese (humans)
Ingestion, milk, cheese, urine, vaginal
B. melitensis:
Pathogenesis and Disease
Pathogenesis: similar to ?
Disease: mainly in ___ and ____
Abortion ___ in pregnancy
Results in?
____ may develop in billies
Clinical signs ___ with immune response?
B. abortus, sheep, goats, late,
Lameness, hygromas (cysts containing serous fluid), and mastitis can occur
Orchitis, abate
B. melitensis: Immunology
* ___ and ____ develop effective protective immune responses
* Infection eventually is cleared
skipped slide entirely
Sheep, goats
B. melitensis: Diagnosis is based on?
* ____ signs
* Direct ____
*** ____ tests (do not need to know specifics; test to screen herd)
Ab tests are used to diagnose
Clinical, culture, Serologic
B. melitensis
Vaccination – Strain Rev 1
* Live _______ strain
* Most effective in preventing ____
* Reduces _____ of organisms
* May localize in _____ and cause _____ in
pregnant animals
avirulent, abortion, shedding, placenta, abortions
B. melitensis
Vaccination – Strain 53H38
* ____________
* Stimulates a more ___________ antibody response than
Strain Rev 1
Inactivated, persistent
B. suis
* Initial isolation: Dr. ______ (1914)
* ________ piglet
* ________ host range than other Brucella species
* Geographic distribution: ________, except ?
* _____ biotypes
Traum, Aborted, Broader, worldwide, Canada, Great Britain, and Ireland, Five
B. suis: Transmission
* Spread usually is ____
List the forms of transmission: (2)
- Wild ____ may serve as a reservoir
- Can ________ in the environment
rapid
- Venereal
- Ingestion – feed contaminated by urine or genital
excretions
hares, persist
B. suis
Pathogenesis and Disease
* Pathogenesis: similar to ?
* Disease: in U.S., prevalence of about 0.1% in domestic and 6% in feral swine
* More common in _____
* Abortion, metritis, spondylitis, orchitis, arthritis. lameness, and paralysis may occur following bacteremia
* Bacteremia may cause ____ and infectious _____
* Most likely pathogen to ______ (?) in U.S. because it is maintained in _____ swine and cannot be eradicated
B. abortus, adults, death, carcasses, humans, abattoir workers, farmers, veterinarians, hunters, feral
B. suis: Immunology
* Females usually recover after several ____; males usually do ___
* Immunity in swine is ___ lived
* Most animals readily become __-______ when re- exposed
* Abortions usually do not occur after the ____ infection
months, not, short, re-infected , initial
B. suis: Diagnosis
* ________ signs
* ___________ culture - probably not done in most labs
* _________ _______ card test considered best; other
serum agglutination tests can also be used –
principle method, but not as effective as with __.______. _____ herd should be tested.
Clinical, Direct, Rose Bengal , B. abortus, Entire
B. suis: Vaccination and Control
* ________: no specific vaccine available, but ____ has shown some protective efficacy in research studies
–> Control
* Best to _____ infected animals
* Certified ____-__ Herd status is determined simultaneously with Pseudorabies control program
Prophylaxis, RB51, eradicate, Brucella-Free
B. canis
* Initial isolation: Dr. __________ (1966); canine ________ in U.S. and Great Britain
* Geographic distribution: ?
* Less virulent for ______
Carmichael, abortion, U.S., South America, Central America, Europe, and Japan, humans
B. canis Transmission
* _____ – primary mode
* ____ transmission – ______ shedding in males
Ingestion, Venereal, intermittent
B. canis Pathogenesis
* Similar to B. abortus
* Bacteremia can
* ______ (periodically occur)
* Persists up to __ years after infection
Make no endotoxins; exotoxins are weak = general statement for brucella
Intermittent, 2
B. canis Disease
* Females can get?
- Abortion – last trimester (about 50 days)
- Lymphadenitis and splenitis may occur
- Infertility
- Sick or stillborn puppies
B. canis Disease
* Males can get?
- Epididymitis
- Scrotal dermatitis
- Testicular atrophy (often unilateral)
B. canis Immunology
* ______ response highest during bacteremia
* Protective immune response probably is _____-mediated
Humoral, cell
B. canis Diagnosis
* Clinical _____
* ____ culture ( ____ method)
* Collect samples from which body sites?
* Best ______ test
presentation, Direct, Best, Blood, bone marrow, lymph nodes, confirmative
B. canis Diagnosis
* Serologic tests - Subject to false ______
* Assays used for serological diagnosis of B. abortus and others do
not work with B. canis because they lack ?
* _____ Slide Agglutination test (for identification of ___ dogs (6o%
false-______ rate)
* ______ assay (reference lab)
* Agar gel ______ and ____ agglutination assays are best and
required if a dog travels to New Zealand or Australia, respectively.
* _______ (serology Gold Standard)
* Negative results usually reliable in ___ infections
positives, O-antigen, Rapid, negative, positive, Immunofluorescence, immunodiffusion, tube, Immunodiffusion, chronic
B. canis: Prophylaxis and Control
* _________________: no vaccine available
–> Control
** ______ is best means of control
* ____ and long term _____ therapy (e.g. streptomycin,
aminoglycosides, doxycycline) ____ best alternative**
Prophylaxis, Euthanasia, Neuter, antibiotic, second
B. ovis
* Initial isolation: ? (1953) in Australia and New Zealand
* Geographic distribution: ________
* Transmission: appears to be _____
* Pathogenesis: similar to ?
, Drs. Buddle and Boyes, worldwide, venereal, B. abortus
B. ovis: Disease
* ______ in rams
* Late _____ in ewes
* Lowers flock _____ rate
* ____ are clinically affected more frequently than ewes
Epididymitis, abortions, fertility, Rams
Brucella: Zoonotic Potential
* Highly infectious for _____
* Relative pathogenicity in humans: ?
* Tetracyclines, Gentamycin, Rifampicin are effectively
used in human beings as combination therapy; ciprofloxacin is popular
humans
B. melitensis > B. suis and B. abortus > B. canis
Brucella: Zoonotic Potential
* Disease in _____
* Lethargy –> Chills
* Malaise –> Night Sweating
* Fever – typically intermittent
* B. abortus and B. suis commonly are ___________
infections
* B. melitensis often affects _________ ________ through
ingestion of ?
humansoccupational, general population, goat milk, cheese, or dairy products
