Chapter 33: Brucella species Flashcards
(95 cards)
1
Q
Size of Brucella
A
Small (0.6 x 0.6 to 1.5 um)
2
Q
Motility
A
Non-motile
3
Q
Shape
A
Coccobacilliary
4
Q
Type of bacteria
A
Gram-negative
5
Q
Environement
A
Aerobic and capnophilic (high CO2)
6
Q
Test for:
-Catalase
-Oxidase
A
-Positive
-Positive (some are negative)
7
Q
Oxidase positive except
A
-B. ovis
-B. neotomae
8
Q
Urease positive except
A
B. ovis
9
Q
Requirement (fastidious)
A
-5 to 10% CO2 for primary isolation
- enriched media with blood or serum for culturing
10
Q
Require 5 to 10% CO2 for primary isolation
A
-Brucella bovis
- some biotypes of B. abortus
-growth of other Brucella spp is enhanced in this atmosphere
11
Q
Requires enriched media with blood or serum for culturing:
A
-B. abortus biotype 2
- B. ovis
12
Q
Referred to as MZN-psotive because
A
They are not decolorized by 0.5% acetic acid in the modified Ziehl-Neelsen (MZN) staining technique
13
Q
MZN-stained smears of body fluids or tissues, characteristically appear as
A
Clusters of red coccobacilli
14
Q
Brucella genome is unusual because
A
It is composed of two circular chromosomes
(except: B. suis biovar 3- single chromosome)
15
Q
Predilection for
A
Both female and male reproductive organs in sexually mature animals
16
Q
Remain viable in
A
moist environment for many months
17
Q
Transmission
A
Direct contact (infected animals/fluids and tissues associated with abortion)
18
Q
Stain ____ using MZN method
A
Red
19
Q
Some species cause ____ in humans
A
Undulant fever
20
Q
Site of replication and dependence on host cells
A
They are intracellular pathogens
21
Q
Usual Host: Cattle
Clinical significance: Abortion, orchitis
A
B. abortus
22
Q
Usual Host: Goats, sheep
Clinical significance:Abortion, orchitis, arthtritis
A
B. melitensis
23
Q
Usual Host: Pigs
Clinical significance:
-abortion
-orchitis
-spondylitis
-infertility
A
B. suis
24
Q
Usual Host: Sheep
Clinical significance:
-Epididymitis in rams
-sporadic abortion in ewes
A
B. ovis
25
Usual Host: Dogs
Clinical significance:
-Abortion
-Epididymitis
-Discospondylitis
-Sterility in male dogs
B. canis
26
Usual Host: Dessert wood rat
Clinical significance:
-not isolated from domestic animals
B. neotomae
27
Usual Host: Cetaceans
Clinical significance:
B. ceti
28
Usual Host: Pinnipeds
Clinical significance:
B. pinnipedialis
29
Species occasionally infected:
-Sheep
-Goats
-Pigs
Clinical significance:
-Sporadic abortion
B. abortus
30
Species occasionally infected:
-Horses
Clinical significance:
-Bursitis
B. abortus
31
Species occasionally infected:
-cattle
Clinical significance:
-sporadic abortion
-brucellae in milk
B. melitensis
32
Species occasionally infected:
-Humans
Clinical significance:
-Malta fever
-severe systemic disease
B. melitensis
33
Species occasionally infected:
-Humans
Clinical significance:
-intermittent fever
-systemic disease
B. suis
34
Species occasionally infected:
-Humans
Clinical significance:
-Mild systemic disease
B. canis
35
Species occasionally infected:
-Dolphins
Clinical significance:
-May cause abortion
-Neurological disease has been described
B. ceti
36
Species occasionally infected:
-Humans
Clinical significance:
-little evidence of disease
B. ceti
37
Species occasionally infected:
-Humans
Clinical significance:
-little evidence of disease
B. pinnipedalis
38
B. abortus:
-Number of biotypes
-Requirement for CO2
-7
-v
39
B. melitensis
-Number of biotypes
-Requirement for CO2
-3
- negative
40
B. suis
-Number of biotypes
-Requirement for CO2
-5
- negative
41
B. ovis
-Number of biotypes
-Requirement for CO2
-1
- positive
42
B. abortus
-production of H2S
-Urease activity
- v
- positive
43
B. melitensis
-production of H2S
-Urease activity
-negative
-v
44
B. suis
-production of H2S
-Urease activity
-v
-positive
45
B. ovis
-production of H2S
-Urease activity
negative
46
B. canis
-production of H2s
-Urease activity
-negative
-positive
47
B. abortus:
Growth in media
-Thionin: v
-Basic fuchsin: v
48
B. melitensis:
Growth in media
-Thionin: positive
-Basic fuchsin: positive
49
B. suis:
Growth in media
-Thionin: positive
-Basic fuchsin: variable
50
B. ovis:
Growth in media
-Thionin: positive
-Basic fuchsin: negative
51
B. canis:
Growth in media
-Thionin: positive
-Basic fuchsin: negative
52
Conducted on bulk milk samples for monitoring infections in dairy herds. Sensitive but may not be reliable in large herds
Brucella milk ring test
53
Useful screening test. Antigen suspension is adjusted to pH 3.6, allowing agglutination by IgG1 antibodies. Qualitative test only, positive results require confirmation by CFT or ELISA
Rose-Bengal plate test
54
Widely accepted confirmatory test for individual animals
Complement-fixation test (CFT)
55
Reliable screening and confirmatory test
Indirect ELISA
56
Recently developed test with high specificity; capable of detecting all immunoglobulin classes and can be used to differentiate infected animals from S19-vaccinated cattle
Competitive ELISA (using monoclonal antibodies)
57
A tube agglutination test which lacks specificity and sensitivity; IgG1 antibodies may not be detected, leading to false negative results
Serum agglutination test (SAT)
58
Sensitive test for detecting non-agglutinating antibodies not detected by the SAT
Antiglobulin test
59
Differentiated by
-colonial appearance
-biochemicsl tests
-specific cultural requirements and growth inhibition by dyes
60
Definitive identification
-agglutination with monospecific sera
-susceptibility to bacteriophages
-Molecular methods
61
Occur in smooth forms, small, glistening, bluish, translucent. Colonies become opaque with age.
-B. abortus
-B. melitensis
-Brucella suis
62
Primary isolates always occur in rough forms. They are dull, yellowish, opaque and friable.
-B. ovis
-B. canis
63
Brucella on blood agar
Non-haemolytic
64
Used to detect presence of important surface antigens
Slide agglutination with monospecific antisera
65
Important surface antigens
-abortus antigen A
-melitensis antigen M
66
Feature of the rough brucellae B. ovis and B. canis, can be detected by anti-R serum
R antigen
67
Isolates of B. abortus is lysed by a specific bacteriophage at routine test dilution
Tbilisi phage
68
Could differentiate between:
-B. abortus biovars 1,2 and 4
-B. melitensis
-B. ovis
-B. suis
AMOS-PCR
69
A new multiplex PCR assay described in the OIE Terrestrial Manual identifies most Brucella species in a single step, including newly describe species from marine mammals and B. abortus and B. melitensis vaccine strains
Bruce-ladder
70
Less virulent Brucella
-lacks outer membrane
-produce rough colonies
-rough forms are usually eliminated unlike smooth which persist and multiply
71
Brucella persist within ____ but not within____
-macrophage
-neutrophils
72
Non-opsonized brucellae are taken up through interaction of the O side- chains of LPS with cholesterol-rich regions of the phagocyte plasma membrane, termed as
Lipid rafts
73
Once engulfed, brucellae persist within the acidified phagosome or
'Brucella-containing vacuole'
74
Is important as it induces changes in gene expression of the Brucella organism, which favor intracellular survival
Acidification of phagosome
75
Constituents of the outer membrane. Helps in the prevention of phagolysosome fusion
Cyclic beta-1,2-glucans
76
Major mechanism for intracellular survival. Important determinant of bacterial virulence.
Inhibition of phagosome-lysosome function
77
Effectors secreted by a type ____ secretion system encoded by the ____. Important in maturation of the vacuole and it's transport to, and fusion with, the rough endoplasmic reticulum
-type IV system
-virB operon
78
Virulent brucellae are transported to
Regional lymph nodes
79
Spread and localization in the reproductive organs and associated glands in sexually mature animals
Intermittent bacteremia
80
-Acts as a growth factor for brucellae.
-Present in high concentrations in the placentae of cattle, sheep, goats and pigs
-Growth factor is also found in other organs such as mammary gland and epididymis (targets of brucellae)
Erythritol (polyhydric alcohol)
81
-Strongly influenced by the stage gestation.
- Increases in late gestation, when the cells actively secrete steroid hormones
Intracellular replication in trophoblastic cells
82
Organisms may localize in joints or intervertebral discs
Chronic brucellosis
83
Responsible in part for the persistent infections seen with this pathogen.
brucellae may inhibit or delay the host immune repsonse
84
Although each Brucella spp has its own natural host,______, ______, and ______ can infect animals other than their preferred host.
-B. abortus
-B. melitensis
-biotypes og B. suis
85
Bovine brucellosis
B. abortus
86
Caprine and Ovine brucellosis
B. melitensis
87
Ovine epididymitis
B. ovis
88
Ovine epididymitis (B. ovis):
-Rams
-Ewes
-epididymitis
-placentitis
89
Porcine brucellosis
B. suis
90
B. suis:
Host: Infects pigs
Brucella suis biovar 1 to 3
91
Brucella suis:
-wild boat (host)
-European hare (reservoir host)
-produces military lesions particularly in reproductive tract
B. suis biovar 2
92
B. suis:
-Infects reindeer and caribou in Northern Canada, Alaska, Siberia
B. suis biovar 4
93
B. suis:
-Infects wild rodents
B. suis biovar 5
94
-Canine brucellosis
- Rough form (low virulence)
B. canis
95
Brucellosis in humans known as undulant fever
Severe:
-B. melitensis (Malta fever)
-B. suis biovars 1 and 2
Moderately severe:
-B. abortus
Mild:
-B. canis
