Week 3 - Bacillus Flashcards
Bacillus anthracis is ______
Bacillus cereus –> not _____
Bacillus thuringiensis –> not _____
Bacillus licheniformis
zoonotic, pathogenic, pathogenic
Bacillus is _____, gram ______.
Large, positive
Bacillus produces _________. When is an un-ideal environment, it is still able to produce _______ which makes them _______, especially in the ____.
endosopores, spores, resistant, soil
Bacillus is an ______ bacteria.
Aerobic
Bacillus grows on ___-_____ media
non-enriched
Bacillus is _____.
motile
Bacillus is Catalase _____, Coxidase ______.
positive, negative
Majority of Bacillus are _____-_______.
non-pathogenic
Bacillus anthracis causes ______ in domestic animals, including ______.
anthrax, humans
Bacillus licheniformis: produces ______ ______ in cattle and sheep
sporadic abortions
alpha toxin is almost common for all the C. perfringes and it has similar biological activities
Bacillus Morphology
_____, in pairs or ____ chains
Rods, long
Bacillus is ______ distributed in the environment
- Endospores can survive ____ than ___ years.
- Resist _______, ____ temperatures, and chemical _______
widely, more, 50, desiccation, high, disinfectants
What is this an image of?
Piece of paper with substrate. When this paper is contact with bacteria sample, the bacteria have the oxidase enzyme, transform or change the color of ?. Tetramthyl-p-…. This chemical compound accepts electrons that are given by oxidase. When this happens, this chemical compound changes from white to blue. The bacillus are negative, so you will not see any change of color here.
Bacillus anthracis
Colonies up to __ mm in diameter, ___, ___, _____ appearance (_____ head at edge of the colony)
No _____.
5, flat, dry, greyish, medusa, hemolysis
What bacteria is this?
What can be seen when you look closely?
Bacillus anthracis
The spore (not stained).
Rod shaped, long chain
Rectangular shape with sharp ends on each side of the bacteria.
What can be seen here?
Bacillus anthracis
No hemolysis seen on blood agar
What can be seen here?
Bacillus anthracis
Medusa head; very characteristic morphology
Bacillus cereus
Colonies similar to ____ ______ but larger with a _____ tinge _______ around the colony
B. anthracis, greenish, Hemolysis
What can be seen here?
Bacillus cereus
Similar morphology to bacillus anthracis
What can be seen here?
Bacillus cereus
Hemolytic (hemolysis of RBC). This is not present in bacillus anthracis
Bacillus licheniform
Colonies are ____, ____, _____ and strongly ____ to the agar
dull, rough, wrinkled, adherent
Spore is rich in _______.
What is important in the formation of spore?
calcium,
Can survive for a long period of time when they are in the spore (Can survive for up to 50 years).
soil rich in ca and nitrogen.
What can be seen here?
Bacillus licheniform
Colonies have rough/dry surface. They attach to the surface of the?
Clinical manifestation of B. anthracis in cattle, sheep.
Very susceptible.
Can develop acute or peracute septicaemic antrhax
Clinical manifestation of B. anthracis in pigs?
Acute anthrax with oedematous swelling in pharyngel region and intestine
Clinical manifestation of B. anthracis in horses?
Subacute anthrax with localized edema, septicemic colic
Clinical manifestation of B. anthracis in humans?
Contact (skin), spore is inhaled, or enters intestine via ingestion.
Clinical manifestation of B. cereus in cattle?
Sometimes can produce mastitis, but is not very common
Clinical manifestation of B. cereus in humans?
Food poisoning, eye infections
Clinical manifestation of B. icheniformis in cattle, sheep?
sporadic abortion; not very common
Describe the epidemiology of Bacillus.
Endospore can survive for long period of time in the soil that are alkaline or contain Ca/N. These spores can contaminate the pasture grasses; the soil, when animals are infected OR when animals die on farm and are buried. –> When it rains or for some reason the water from underground rises to the surface and carries spores –> spores are ingested/inhaled/contact with skin.
Describe the pathogenesis of Bacillus
Capsule provides resistance to phagocytosis
Toxins components: Protective antigen (helps bacteria binding moiety), edema factor (toxic for ?) and lethal factor.
Neutrophils is the target of the edema factor.
Macrophages, dendritic cells neutrophils and some epithelial and endothelial cells are
the target of the lethal factor
Describe the clinical signs of Bacillus
Clinical signs: Cattle and sheep are more susceptible and develop fever, depression, congested mucosae and petechiae, eventually abortion.
When animals die, it is not recommended to do necropsy. Usually report it to health agencies must dispose the body properly.
Describe the lesions caused by Bacillus
Lesions: rapid bloating, incomplete rigor mortis, ecchymotic hemorrhages and oedema, blood is dark, unclotted blood and blood stained fluids in cavities, extremely large soft spleen (main characteristic in cattle).
How do you diagnose Bacillus?
- Presence of unclotted blood in mouth, nostrils and anus.
- Do not open the carcasses.
- Blood sample or fluids Gram staining
- Bacterial culture Blood agar: 37C, 24-48h.
- PCR
- Ascoli test, precipitation or gel diffusion
How do you treat cases of Bacillus?
- Penicillin, oxytetracyclin
How do you control Bacillus in endemic regions?
Annual vaccination –> Sterne strain, live vaccine, the spores convert in non-encapsulated avirulent
vegetative organisms.
How do you control Bacillus in non-endemic regions
- Avoid movement of animals
- Personnel must wear PPE
- Foot baths (formalin + peracetic acid)
- Immediate disposal of carcasses
- Lock all buildings and fumigate with formaldehyde)
What can be seen here?
Characteristic lesion caused by Anthrax in humans
What is this graphic depicting?
Inhalation of spore/ingestion/by flies or mosquito that carries bacteria
What can be seen here?
Contaminated animal dies –> bacteria starts to produce spores –> spores in ground can be transported during rainy season to another farm.
Fumigate with bacteria, 45 degrees Celsius
Characteristics of Clostridiums
• ______ or ______ ____ rods.
• Produce ______. The ___, ____ and ____ of the endospores can be used for species differentiation.
• More than ___ species but less than __ are pathogenic.
Straight, slightly, curved, endospores, size, shape, location, 100, 20
rods can be in pairs; ends are more rounded.
Clostridial cultures typically emit ____ ____
putrid odors
Tissue degradation produces a lot of gas. Usually different type of volatile fatty acids, which produces this odor.
Peptide catabolism is the?
most common mode of energy production by clostridiums
What is this graphic showing?
Spore at the end of the rod. When spore is located on one end, we can characterize the spore as a terminal spore. If the spore is in the center, is it called central spore.
If between center and end it is subterminal.
Anthracis = center
Clostridia are ______, they constitute part of the ______ _____ flora and some may be
sequestered as _______ in _____ or ____. Sequestered endospores, if _____, may produce disease
saprophytes, normal intestinal, endospores, muscle, liver, activated