Brucella Flashcards
General features
Gram negative
Short rods (coccobacilli)
Aerobic
Some carboxyphilic
Facultatively intracellular pathogen
Oxidase positive
Classical brucella
abortus
suis
melitensis
-Potential bioweapons
-Highly infectious
-Easily aerosolized
-difficult to detect
Transmission
Oral (ingestion or milk from infected cows to calves) or venereal
Brucellosis
Infectious of the repro organs
-Cause abortions
-Zoonotic disease
Erythritol
Growth factor in placenta and testicles (not in humans) some species of brucella require
Geographic distribution
Worldwide
Considered eradicated in US
Virulence factors
-Endotoxin
-Ability to survive in macrophages
Diseases
-Contagious abortions
-Infertility, mastitis
-Bulls: orchitis and epididymitis. Affects joints
Lesions
Granulomatous and suppurative
Diagnosis
-Difficult in bulls and nonpregnant (asymptomatic)
-Suspect if see multiple abortions
-Examine cultures
-PCR assay for species confirmation
-Serology
Treatment
Can not treat in food animals -Slaughter
Treat dogs with aminoglycosides or tetracyclines
Vaccines
-Live attenuated strain only for females causes sterility in males (not used)
-RB51 strain-cell mediated immunity for all adults
National Brucellosis Eradication Program
- Detect infected animals
- Reactors branded and slaughtered
- Herds with suspects are quarantined
- Vaccination of calves
Class free
No positive herd for one year or if there was one they kill the herd and thoroughly test all adjacent herds
Brucella suis
Can infect any animal
Transmission of brucella suis
-Ingestion
-Nursery pigs from infected sows
-Venereal
B. suis signs
-Abortion
-Sterility
-Still births
-Spondylitis
-Abscesses
Control of B. suis
Eradicated
Brucella ovis
Least pathogenic
Transmission of B. ovis
Venereal
Signs of B. ovis
-Epididymitis in rams
-Abortion and infertility
Brucella canis
Only infects dogs
Transmission of B. canis
Oral and venereal
highly contagious
Pathogenesis of B. canis
Secreted in vaginal secretion, urine, or semen-> gets phagocytized-> ln->blood->repro tract
B. canis signs
Abortion and infertility
-Persistent vaginal discharge with canis
-Epididymitis and prostatitis
-Testicular atrophy and sterility
Diagnosis of B. canis
- Culture or PCR
- Necropsy
- Serology: agglutination test
Treatment of B. canis
-Aminoglycosides
-Tetracyclines
-Doxy with gentamicin
-Long term
Prevention
No vaccine
Kill infected animals
Brucella in horses
-Arthritis
-Atlantal bursitis (poll evil)
-Supraspinatus bursitis (fistulous withers)
Brucella in goats
Melitensis most common
-Abortion
-Orchitis
Brucella in humans
Melitensis most serious infection (Malta fever)
-Changed from occupational to foodborne disease
Signs of brucella in humans
Chronic fatigue syndrome
-Long incubation period
-Undulant fever
