Q-Fever Flashcards
- What are the other names that Q-fever goes by?
a. • Query Fever
b. • Coxiellosis
- What is the causative agent of Q-fever?
a. . Coxiella burnetti
- Is Coxiella burnetti gram positive eor gram negative?
a. Graham neg
- Is Coxiella burnetti a spore former?
a. Yes
- Can pasteurisation kill Coxiella burnetti?
a. Yes
- Coxiella burnetti exists in ______ antigenic phase
a. Two
- What are the two antigenic phases that Coxiella burnetti exists in?
a. •Phase 1: virulent
b. •Phase 2: less pathogenic
- What is the phase 1 of Coxiella burnetti?
a. Virulent
- What is phase 2 of Coxiella burnetti?
a. Less pathogenic
- Where does Coxiella burnetti replicate?
a. Monocytes or macrophages
- What was Coxiella burnetti thought to be originally and why?
a. Rickettsial agen
b. Transmitted by tick
- What phylum does Coxiella burnetti belong?
a. Proteobacteria.
- What other bacteria are part of the proteobacteria?
a. Legionella and salmonella
- What percentage of bacteria are proteobacteria?
a. 32%
- All proteobacteria are Gram Positive (t/F)
a. False
- Is Coxiella burnetti an environmentally stable organism?
a. Yes
- Why is Coxiella burnetti able to be so resistant to deissinfection agents that normally kill bacteria?
a. Its spore structures
- How long can Coxiella burnetti spore survive in room temperature outside of a host?
a. 7-10 days
- How long can Coxiella burnetti spores survive in a fresh meat stored at 4C?
a. A month
- How many day s can Coxiella burnetti spores survive in dust?
a. 120days
- How long can Coxiella burnetti spores survive in skim milk?
a. 40 months
- How can Coxiella burnetti spores be killed?
a. pasteurisation
- What is the phase that Coxiella burnetti is most commonly found?
a. Phase 1
- When is phase 2 of Coxiella burnetti typically discovered?
a. Through multiple passes of cell culture in the lab.
- Phase one is a _________ infection whereas phase two is a ________ infection.
a. Chronic
b. Acute
- How does Coxiella burnetti infect macrophages?
a. Binds to an αvβ3 integrin: Triggering phagocytosis
i. This is an actin dependent mechanism
b. Nascent (beginning once inside the cell) Coxiella-containing vacuole (CCV) acquires early endosome markers
i. RAB5 , EEA1 and microtubule-associated protein light-chain 3 (LC3 - autophagosome marker)
ii. This can take place within 5 minutes of the bacterium being internalised
c. Autophagosome binds to the nacent CCV
i. Lowers the pH to ~5.4
d. Maturing CCV acquires RAB7 and lysosome-associated membrane glycoprotein 1 (LAMP1)
i. The pH then decreases even further ~5 pH
e. Lysosomal enzymes – eg cathepsin D (CTSD) start to accumulate
i. pH drops again to ~4.5
ii. This happens within 2 hours of internalisation
f. Conversion of bacteria from small cell variants (SCVs) to metabolically active large cell variants (LCVs) - involves the recruitment of both RHO GTPase and RAB1B
i. RAB1 is recruited from the endoplasmic reticulum thought to acquisition of additional membranes to create a large vacuole
- What is the estimated life cycle from invasion of macrophages to production of large replication vacuoles?
a. 20 hours
- _________ – Febrile disease -Abattoir workers, Brisbane: What was the desease called at this stage and why?
a. 1935
b. Query fever
c. As the cause fo the disease was unknown
- The disease is named after a scientist called _____?
a. Burnet
- _________ Montana, USA – pathogen isolated from ticks in the nine mile.
a. 1938
- ________ the bacterium got the name coxella burnetti because of the two scientists
a. 1938
- ______ a lot of cases being reported amongst military personal, both USA and British, in Mediterranean particularly Italy
a. 1940
- In the 1940s those in cities became ill form Coxiella burnetti, these cities where down wind of infected farmsm, which led to what discovery
a. The disease is Airborne
- Ho can Coxiella burnetti be transmitted?
a. Aerosol
b. Direct contact
c. Fomites
d. Ingestion
e. Ticks: Arthropods
- What is the most common animal to spread Coxiella burnetti to humans and through what transmission route?
a. Cows, sheeps, and goats
b. Aerosols
- How can aerolisation of Coxiella burnetti happen?
a. Parturient fluids
i. • 109 bacteria released per/gram /placenta
b. – Urine, faeces, milk
c. Blood from meat plants
- What is a parturient fluid?
a. Birthing fluids
b. NASSSY
- What fomites can be an issue?
a. Can survive on clothes for 7-10 hours
b. Can survive on animal bedding and other items
- How is Coxiella burnetti typically consumed?
a. Unpasteurised milk
b. Infected meats
c. Placenta when eaten by animal, including pets