Flashcards in 24-Zoonosis Deck (61)
Regarding bioterrorism select agent classification, there are 3 categories (A,B and C). Which is most dangerous and which is least dangerous?
A is most dangerous (easily disseminated) while C is least dangerous (requires engineering to become easily disseminated)
Yersinia pestis, Fransicella and Brucella are all select bioterrorism agents. What categories do they belong to?
Yersinia and Fransicella are in A while Brucella is in B.
There are 4 biohazard safety levels based on the disease causing ability and difficulty to treat various diseases (agents). What level do Yersinia pestis, Brucella and F. Tularensis belong to?
All are level 3 (Potentially lethal if inhaled, vaccine or treatment available)
What are the 3 Yersinia pathogens?
Pestis, enterocolitica and pseudotuberculosis
What yersinia subtype is characterized by bipolar staining and is a facultative intracellular parasite?
What yersinia subtype is associated with bubo formation, and bacteria in the blood stream?
Why is the bubonic plague called black death?
It causes vascular thrombi (petechia) in skin
What is the cause of death with bubonic plague?
Sepsis leading to hypotension and death
What is the vector for yersinia pestis? This vector is also the cause of epidemics
What disease arises when bubonic plague remains untreated and spreads to the lungs?
True or false: Both bubonic and pneumonic plague are spread person to person?
False, only pneumonic is
Regarding the urban vs. sylvatic plague, what are their respective reservoirs?
Urban plague - rats, while sylvative plague - prairie dogs (also domestic cat)
True or false, urban and sylvatic plague are what lead to pneumonic plague?
False, they both cause human infection and cause bubonic plague
What is the most common type of plague seen in the US? Where in the US?
Sylvatic plague, mainly in the western US
What is the vector for the sylvatic plague?
Fleas assoc. with wild rodents
What are the 4 corner states associated with plague?
New Mexico, Utah, Arizona and Colorado
What type of bubonic plague is likely to result in isolated cases? What about epidemic?
Sylvatic is likely to be isolated, urban likely to be epidemic
When was the last recorded case of bubonic plague in the US? Where?
November 2002 in NYC
What are the 3 major virulence factors unique to Yersinia pestis?
Yops, F1 antigen and Type 3 protein secretion system
What is the function of Yops?
Allows entry and survival inside macrophages (prevents engulfment)
How are Yops delivered into the host cell?
Type 3 protein secretion system (like a hypodermic needle)
What is the function of the Yersinia F1 antigen?
Antphagocytic to neutrophils
True or false, Yersinia grows slowly in the blood and has pigmentation for iron acquisition.
False, It grows fast AND has pigmentation for iron acquisition
What is the cause of Yersinia associated DIC and surface purpuric lesions?
What are the 2 components of Yersinia virulence factor regulation?
Calcium and temperature
True or false, Yersinia's virulence factors are on plasmids?
True. Check our slide 26 in the notes for details on all 6
What plasmids is associated with Yops, F1 antigen and Type 3 protein secretion system ?
How is Yersinia Pestis diagnosed? Where would you get a sample from?
DIrect fluorescent antibody, stain a sample from a bubo aspirate
How would you treat yersinia pestis? What are 2 components of this treatment?
Antibiotics (Streptomycin and tetracycline)