Flashcards
Brucella
Flashcards do conjunto (48)
- 1How many species of Brucella are there?7 according to Europe
(1 according to US) - 2What are general features of Brucella?1. Small G-ve coccobacilli (0.5-0.7 x 0.6-1.5microm)
2. Non-motile
3. Non-sporing
4. Catalase +
5. Oxidase + (variable)
6. Aerobic
7. Fastidious
Blood / serum YES
BLA NO
Selective media YES - 3What type of parasite is Brucella?Intracellular - can be infected for life
- 4Why won't Brucella grow on bile lactose agar?Not an enteric pathogen
- 5Name the 7 species of Brucella.B. abortus
B. melitensis
B. suis
B. ovis
B. canis
B. neotomae
B. maris - 6What are the hosts and diseases for B. abortus?CATTLE : placentitis, mastitis, abortion, orchitis
Humans : undulant fever - 7What are the hosts and diseases for B. melitensis?GOATS, sheep : abortion, mastitis, orchitis
Humans : undulant fever (Malta fever) - 8What is the species of Brucella that humans are likely to get?B. melitensis
(into joints causing arthritis) - 9What are the hosts and diseases for B. suis?PIGS : abortion, orchitis, infertility, arthritis, spondylitis
Humans : undulant fever - 10What are the hosts and diseases for B. ovis?SHEEP : placentitis, abortion, orchitis, epididymitis, infertility
- 11What are the hosts and diseases for B. canis?DOGS, foxes : abortion, epididymitis, osteomyelitis, spondylitis, permanent infertility in males
Humans : undulant fever - 12What is the classification for Brucella species be separated?Species (UK)
Biotypes (US) - 13How can you determine species/biotypes?1. Urease activity and H2S production
2. CO2 requirement
3. Sensitivity to dyes (basic fuchsin & thionin)
4. Phage typing - Presence of antigens
A and M : B. abortus, B. melitensis, B. suis
R : B. ovis, B. canis - 14Is Brucella a zoonotic? and how is it passed?Yes - passed by contact and by aerosol.
Highly infectious - 15What is the natural habitat of Brucella?Host - obligate pathogen - won't survive long outside of the host
- 16Describe the environmental survival of Brucella.Few hours unprotected in sunlight
Days protected by urine/aborted material
Months protected by damp/cool weather - 17Is there a reservoir for Brucella in wild animals?Yes
- 18What is the only Brucella species that can be found in animals in the UK?B.canis brought on travelled dogs
- 19What is the only Brucella species that can be found in humans in the UK?B.melitensis
B.canis rare - 20Why worry about Brucella?1. Common in other parts of the world
2. Zoonotic problem
3. Used to be in the UK
- Pasteurisation
- Eradication scheme
4. Could still be imported
5. NOTIFIABLE - 21What are the routes of infection of Brucella?1. Mucous membranes :usually ingestion
2. Via unbroken skin
3. Venereally
4. To calf in utero
5. To calf via milk - 22What is the pathogenesis of Brucella?1. Predilection for reproductive tracts (RT)
- Erythritol - stimulates growth of B.abortus/melitensis/suis
- High levels in male/female RT
- Absent from human RT
2. Survival in PMNs and macrophages
3. Persistence in macrophages - 23What is the pathogenesis for humans and why?Fever, arthritis
Not reproductive tract due to not having erythritol which is what Brucella is attracted to - 24Why is it not a problem that the infant is colonised and killed?The foetal matter is also contaminated and will help spread to other animals
- 25What is the main way of identifying an outbreak of Brucella?Abortion storms (all at once)
- can't treat due to all being affected at once - 26Why is Brucella found in the faeces?- Shedding in the intestines - not a point at which the Brucella will attack
- 27What affect can Brucella have on the placenta?Inflammation and erosion
- 28What can cause persistent shedding in the sperm?Granuloma in the testis and epididymis that can burst
- 29What is the immune response?1. IgM and IgG
2. Cell mediated immune response
- Cleared from genital tract
- Persist in RES and udder
3. Carrier animals
- Abort once
- Less severe infection at subsequent pregnancies
- Excrete in udder + uterine discharge - 30How can you get rid of Brucella?Kill infected animals
- 31What are the problems with calves born to carrier cows?1. Infected in utero or via milk
2. Prepubescent = relatively resistant
3. Develop a good immune response
4. Most clear infection and remain R
5. ~ 2% retain latent infection
Source of infection for others
Have infected calves themselves - 32What are the major concerns with economic losses?1. Abortions
2. Decreased milk yield
3. Long term udder damage + milk loss
4. Arthritis / bursitis - 33What are the major concerns with ease of transmission to humans?- Flu like illness
- Recurrence - bones/heart/fatal - 34What is the B.abortus eradication scheme?1. Identify infected herds
2. Identify infected individuals
3. Cull infected individuals
4. Herd restrictions - 35What is the compensation to farmers for infected animals?75% of market value
- 36What are the herd restrictions?- Retested at 8 months and 12 months
- No positives -> restrictions lifted
- Positives -> culled (with dangerous contacts) + herd tested every 2 months until cleared - 37What are the regular testing programmes for B.abortus eradication?Dairy herds – monthly
Beef cattle – every 2 years
Imported cattle
Abortions - 38How can you ID infected herds?ELISA on bulk milk - quarterly by APHA
- 39How can you ID infected individuals?1. Bacterial culture
2. Direct microscopy
- Immunofluorescence
- Modified Ziehl-Neelsen
3. PCR - 40What ways of identifying infected individuals can be used when technology isn't available?1. Guinea-pig inoculation
2. Serology
- Slide agglutination (card test, plate test)
- ELISA
- Serum agglutination test (SAT)
- Complement fixation test - 41What was the initial vaccination?Strain 19
- 42What are features and issues of Strain 19?Live attenuated
Rarely shed in milk
Huge doses needed -> abortion in cows
Non-transmissible
Female calves @ 2-5 months
Male calves not vaccinated
Adults develop persistent antibodies
Infects humans! - 43What were features of strain 45/20?- Killed bacterin (rough mutant)
- Less effective but adults don’t develop persistent antibody levels - 44What is a bacterin?No LPS - less dangerous (antigen preparation)
- 45What are features of RB51?- Licensed for us in US
- Stable rough mutant
- Good protection v abortion
- Ab’s don’t interfere with serological tests - 46How can Brucella be isolated?- Isolate from blood culture on Castaneda’s medium. Simultaneous solid and liquid culture
- Prolonged incubation >6 weeks
- Must be differentiated from Salmonella. Brucella is urease positive
- B. abortus requires elevated CO2 - 47What is the main treatment for Brucella?Kill
- 48What treatment has been used on a very small scale?Oxytetracycline and streptomycin has shown efficacy
Informações
- Descrição
- Animal Disease 2 (Specific Bacteria - TC) FlashCards sobre Brucella, criado por Rachael Jones em 09-10-2017.
- Criado por
- Rachael Jones
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