Bacillus (B. Anthracis) Pseudomonas And Burkholderia

Front 1

Is there anything in common between the 3 genera of Bacillus, Burkholderia and Pseudomonas species?

Back 1

- environmental organisms (not transmittable)
- important exotic diseases (scheduled and notifiable) and control by slaughter
-some zoonotic

Front 2

Bacillus species are characteristic for what?

Back 2

large gram positive rods

endospores

Front 3

How many species of Bacillus are there?
How would you classify most of them?

Back 3

200 species

most are saprophytes

Front 4

Name 3 important pathogens of Bacillus species.

Back 4

1. Bacillus anthracis
2. Bacillus cereus (causes food poisoning)
3. Bacillus licheniformis.

note: (Clostridium piliforme) was the former name for Bacillus

Front 5

Bacillus ID (in general)

Back 5

large Gram + rods
endospores produced
aerobic or faculatative anaerob
non-enriched media
Most motile
Most catalase +
Most oxidase -

Front 6

Bacillus epidemiology:
B. anthracis

Back 6

most non-pathogenic environmental
SPORES survive long periods (50yrs) in soils
Wide spread: air, soil and water.

Front 7

B. anthracis epidemiology

How do spores survive?

Back 7

Spores build up
- alkaline, fertile soil
- organic matter
- low lying areas

major outbreaks in summer, end of drought
major earthworks (EARTHWORMS)
infection by infestation in animals

Front 8

B. anthracis epidemiology

What leads to spore formation in the host?
( how are animals infected?)

Back 8

1. infection through grazing, flies contaminate herbage

2. infection by animal to animal transmission:
B. anthracis is shed by haemorrhage from orifices or through scavenging

Front 9

B. anthracis epidemiology

What is the extent of sporulation in the host once ingested from environment?

Back 9

Many factors

** vegetative form in host.

nutrient depletion and temperature are important for spore formation.

Front 10

B. anthracis epidemiology

why are susceptible species unequally affected in same area?

Back 10

Difference between browsers and grazers.

Grazers eat grass which could be contaminated by flies.

* this is why Anthrax is now more in wildlife.
ex. cattle in Texas

Front 11

B. anthracis Pathogenicity

How are virulence factors encoded and gene expression regulated by host?

Back 11

2 plasmids- (Both target the host immune response)

pXO2- capsule (poly - y- D- glutamic acid)

pXO1- two exotoxins
Oedema toxin-
impairs phagocytosis/alters cytokine production.

Lethal toxin-
death of macrophages,
impairs Ig production by B cells,
disrupts toll like receptor signaling

Front 12

Describe the unique characteristics of the capsule of bacillus anthracis

Back 12

It is a polypeptide capsule that inhibits complement fixations; it is similar to the M protein of group A strep

Front 13

Describe the exotoxin of bacillus anthracis

Back 13

It consists of three proteins: the edema factor, protective antigen, and the lethal factor; the lethal factor and the edema factor must be bound to the protective antigen in order to function

Front 14

Describe the function of the protective antigen of the bacillus anthracis exotoxin

Back 14

It binds to host cell surfaces and facilitates the entry of the edema factor and lethal factor

Front 15

Describe the edema factor

Back 15

It is an adenylate cyclase that increases the intracellular cAMP, leading to cellular swelling

Front 16

Describe the lethal toxin of bacillus anthracis

Back 16

It is a protease that cleaves MAP kinases, disrupting cellular signaling and leading to cell death

Front 17

B. anthracis Pathogenicity

Where do endospores germinate and where do they go in the body?

Back 17

initially germinate in macrophages
multiply in bloodstream
carried to lymphatics

Front 18

B. anthracis Pathogenicity

What is the result of B. anthracis in lymphatics and bloodstream?

Specifically the lethal toxin?

Is there anything that increases toxin production?

Back 18

septicaemia, toxaemia and death

Lethal toxin: causes shock through myocardial dysfunciton and disruption of vasculature

Toxin production is increased by High CO2 and 37c

Front 19

B. anthracis disease

Back 19

cattle: fever, depression, resp distress, congestion -> sudden death; haemorrhage; rapid bloating and incomplete rigor mortis; splenomegaly

swine and horses: edema of throat and head;

Man: cutaneous black scars and septicaemia, pulmonary rapid death

Front 20

B. anthracis diagnosis

Back 20

clinical signs
PM signs (do not open carcass, it will facilitate spread)
Culture: MAC (no growth) and BA
PCR, blood smears with Giemsa or M'Fadyean's polychrom methylene blue (dyes capsule pink)

Front 21

B. anthracis control if outbreak or endemic

Antibiotics?
Vaccination?

Back 21

Penicillin G if given early enough may help

Vaccination (Sterne vaccine (lack pXO2, no capsule), and chemoprophylaxis

Front 22

B. anthracis control in countries free of anthrax

Back 22

protection and surveillance zones
control movement and pest animals
disposal of carcasses
fumigate contaminated buildings * best form
disinfect (spores very resistant though)

Front 23

Bacillus licheniformis

source?
what does this cause?

Back 23

source: poor silage

causes: sporadic abortion in cattle
* so does Listeria and Fungi... be careful

Front 24

Psuedomonas Spp
- how to ID and other important features

which organism should we know?

Back 24

Gram-negative rods, medium sized
ubiquitous in environment
most exclusively saprophytes (like moist areas)

Psuedomonas aeruginosa

Front 25

Psuedomonas Spp.

What is the pathogen type?
What is the source?

Back 25

OPPORTUNISTIC.

point source ( traced back to one source)
nosocomial (moisture)

Front 26

Psuedomonas Spp
What does this species cause?

Back 26

wound, ear, urogenital infections, mastitis

Fleece Rot

Front 27

Psuedomonas Spp
What are the Virulence factors that cause severe inflammation?

Back 27

flagella, endotoxin, TTSS delivers effector proteins, Exotoxin, exoenzymes, siderophores, biophilm

Front 28

Psuedomonas Spp

Is there resistance?

Back 28

Yes, resistant to many drugs and disinfectants

Front 29

What is Burkholderia mallei?

Back 29

Glanders
* former name was psuedomonas

Front 30

What is Glanders- Burkholderia mallei?

Back 30

Horses, donkeys and mules
primary pathogen- (of cystic fibrosis)
zoonosis
last case in Ireland 1920
scheduled (class A) and notifiable
Gram negative rod

Front 31

Why do we care about Glanders- Burkholderia mallei since the last case in Ireland was in 1920?

Back 31

international transport of horses.

* Iran, Iraq, Brazil, mongolia, china

Front 32

Glanders- Burkholderia mallei

Epidemiology

Back 32

Clinically and subclinically infected Equidae
little resistance- will not survive >2 weeks outside the body
WAR (Iran and Iraq, disease control break down)

Sheep, dogs, cats can be infected but do NOT maintain the disease.
(aka don't shed the organism... dead end host)
needs to be tight control

Front 33

Glanders- Burkholderia mallei

characteristics

Back 33

2 small chromosomes (host restricted)
DANGEROUS (to work with in lab)
culture of pus of exudate

Front 34

Glanders- Burkholderia mallei

Diagnosis

Back 34

grows on BA with 1% glycerol @ 37c
no growth on MAC
CFT (common fixation test)
Mallein test
Strauss reaction (lab animal test)
PCR

Front 35

Burkholderia mallei

Glanders Disease
acute vs chronic form
cutaneous form

Back 35

affects lungs
acute form- mules and donkeys, septicaemia nad bronchopneumonia

chronic form- HORSES
'Farcy'- cutaneus form

Front 36

Glanders- Burkholderia mallei

why are horses special?

Back 36

Chronic pneumonia or chronic farcy are the source.
ONLY HORSES

Front 37

Burkholderia mallei
Treatment and Control

Back 37

Treatment not advised. HORSES SHOT
scheduled and notifiable in EU (imports strictly controlled)

outbreak, slaughter all clinical cases
movement restriction on in-contacts and Mallein test every 28 days- slaughter eactors

Front 38

Burkholderia pseudomallei- Melioidosis
* don't worry about this organism

Back 38

gram negative rod
2 chromosomes
many animal species including man
exotic to EU
tropics and subtripics
Habitat: soil
DISEASE
ex. soldiers from vietnam war get signs years later
chronic disease: abscessation of internal organs

Front 39

SUMMARY of Bacillus/Burkholderia/Pseudomonas

Back 39

Environmental organisms
B.mallei= exception, has become host adapted
specific virulence factors
some major pathogens- specific controls
Pseudomonas- sporadic opportunistic infections but can cause outbreaks
Pseudomonas- antimicrobial resistance.

Front 40

Bacillus anthracis colony morphology

Back 40

non-motile
flat, dry, greyish colored colonies with irregular edge
Polyglutamic capsule (not polysaccharide)

Front 41

B. licheniformis colony morphology

Back 41

dull, opaque, rough, wrinkled colonies that appear "lich-like". The colonies are strongly adherent to the surface of hte agar and hair-like growth from colonies are common

Front 42

Which bacillus species causes Anthrax?

Back 42

B. anthracis

Front 43

Which Bacillus species causes Food poisoning?

Back 43

Bacillus cereus

Front 44

Which Bacillus Species causes sporadic abortions in cattle, sheep?

Back 44

B. licheniformis

Front 45

Under direct microscopy, how would B. anthracis appear?

Back 45

polychrome methylene blue stained (blood smears)
M'Fadyean rxn: square ended, blue staining rods in short chains surrounded by pink capsular material.

Front 46

How is B. anthracis isolated in lab?

Back 46

Blood agar aerobically at 37c for 24-72 hours

Front 47

Annual outbreaks of anthrax are common in what animal populations?

Back 47

Livestock and wild game animals such as deer