Bacillus Flashcards
Describe Bacillus species - gram, spores?
gram positive
spore forming
non-bulging
where are Bacillus species found?
soils, decaying organic material, water, human microbiota
what Bacillus species is responsible for anthrax and is nonmotile?
B. anthracis
what Bacillus species causes sporadic abortions in sheep/cattle?
B. licheniformis
what Bacillus group is Bacillus anthracis in?
Bacillus cereus sensu lato group
what is the infectious agent in Bacillus anthracis? how long is is it viable?
spores and viable for years
What must be done since Bacillus anthracis is a CDC category A priority pathogen?
report if you have suspected or confirmed infection
What is Sap in the S-layer of Bacillus anthracis?
primary protein during exponential growth
what is EA1 in the S-layer of Bacillus anthracis?
replaces Sap as cell enters stationary growth phase - strong target for vaccines
Are all B. anthracis strains virulent in humans?
no
what is the significance of pXO1 in B. anthracis?
extrachromosomal plasmid carrying lethal factor (LF), edema factor (EF), and protective antigen (PA)
Can LF cause disease on its own? How does it cause disease?
no it need PA
LF + PA -> lethal toxin
cleaves host cell MAP kinase proteins
Can EF cause disease on its own? How does it cause disease?
no it needs PA
EF + PA -> edema toxin
inc cAMP levels in host cell > swelling and edema (imbalance of ions)
what is the significance of pXO2 in B. anthracis?
encodes for capsule production (inhibits phagocytosis)
capBCDAE operon encodes genes necessary for poly-y-D glutamic acid capsule
what population is anthrax a primary disease of?
herbivores
what are the routes of infection of B. anthracis?
inoculation
ingestion
inhalation - NOT PENUMONIA
How do cattle, sheep, and goats present when infected with B. anthracis?
peracute - extremely rapid progression, illness often not observed b/c so rapid
what helps indicate this cow was infected with B. anthracis?
How do horses present when infected with B. anthracis?
Which animal once infected with B. anthracis die first - cow or horse?
cow
How does a pig infected with B. anthracis present?
sudden death, oropharyngitis, or mild, chronic form
what is oropharyngeal anthrax characterized by?
rapidly progressive swelling of throat
What should you not do with the carcass when onsite of a B. anthracis case?
do not open carcass - promotes endospore formation
what sites do B. anthracis cases usually have unclotted blood from post morteum?
mouth, nose, anus, vulva
How is B. anthracis diagnosed?
sample sources with PPE
y-phage lysis
M’Fadyean stain (polychrome methylene blue)
BaDxx - growth chamber and later flow detection
Tetraacore Redline Alert - lateral flow detection
why is y-phage lysis useful in diagnosing B. anthracis?
y-phage is specific to B. anthracis (and handful of B. cerus isolates)
Are bacterial strain static?
no
Since B. cereus has been shown to be naturally competent in some conditions what does it suggest about B. anthracis?
would also be competent
what other Bacillus species can cause anthrax? How?
How is anthrax prevented?
vaccination of animals - live culture of strain with no pXO2
How are infected carcasses infected with anthrax handeled?
incinerate carcasses and burn soil during incineration
How are animals treated that are infected with anthrax?
penicillin G or oxytetracycline
How are humans treated that are exposed to anthrax if inhalation anthrax is possible?
doxycycline and ciprofloxacin for 60 days
latency in spore germination requires lengthy abx course
what are the antibodies that treat humans infected with anthrax? what are they antibodies to?
Obiltoxaximab and Raxibacumab - monoclonal antibodies to PA
Based on the spore location what is each bacteria?
