Borellia & Rickettsiae

Question 1

Other organism that can fit into this category

Answer 1

Yersinia pestis

Question 2

Borrelia organism size, shape, and visualization

Answer 2

.4um

spirochete (long)

Light microscope visible

Question 3

Borrelia gran staining

Answer 3

Gram negative

*but NO LPS

Question 4

Borrelia contains _________ in outer membrane

Answer 4

inflammatory proteins

(OspA + OspC)

Question 5

B recurrentis and B hermsii cause _____.

Three stages of symptom progession?

Answer 5

Relapsing fever

• General bacteremia (within one week)
• Sudden onset fever, subsides in 3-5 days
• Recurrence of symptoms 5-10 days

Question 6

Symptom recurrence of B. recurrentis + hermsii caused by _________

Answer 6

Antigenic variation

may go through 5-10 cycles

Question 7

What is the most common Borellia?

What does it cause?

Answer 7

burgdorfi

Lyme disease

Question 8

Symptoms of lyme disease (early, and chronic)

Answer 8

Early = Flu-like, erythema chronicum migrans

*Early disseminated symptoms = CN7 palsy, meningitis

Chronic infection = arthritis, joint pain (may affect heart and nerves)

Question 9

What is behind the pathology of borrelia symptoms?

Answer 9

Autoimmune antibodies

Question 10

Is borrelia Human > Vector > Human transmission possible?

Answer 10

Only with recurrentis (relapsing fever borrelia)

Question 11

B. recurrentis spread via ______

Answer 11

human louse

(innoculated when louse is scratched into skin)

Question 12

B. hermsii is spread via…

Answer 12

soft-bodied ticks from rodent reservoir

(transovarian cycle in the tick)

Question 13

Many ticks in western US are infected with B. hermsii, but…

Answer 13

outbreaks are rare

Question 14

B. burgdorferi spread via…

Answer 14

Deer tick nymph (lxodes scapularis)

*from deer, mouse, or bird reservoir

Question 15

Up to ___% of ticks are infected with B. burgdorferi

Answer 15

50%

Question 16

Main virulence factor for B. recurrentis + hermsii

Answer 16

antigenic variation

Question 17

Antigenic variation of borrelia is based on ________

Answer 17

VMP protein antigen

• *Most population has one form, but a few mutants have another one
• *host antibodies select against the mutants

Question 18

Borrelia (recurrentis and hermsii) latency is when…

relapse is when…

Answer 18

Latency = most of the population has been killed

Relapse = mutant variety grows to repopulate

Question 19

B.burgdorferi antigenic variation

Answer 19

doesn’t occur

Question 20

Why do you get multiple rounds of symptoms with burgdorferi if it doesn’t undergo antigenic variation?

Answer 20

Probably a second infection with a different strain of burgdorferi

Question 21

Preventive control of B. burgdorferi

Answer 21

hygenic delousing

long pants

check body for ticks

Question 22

Antibiotics for Borellia

Answer 22

Doxycycline or synthetic penicillins

*Can use 3rd gen ceph for recalcitrant (uncooperative) infections

Question 23

Borrelia vax?

Answer 23

No effective vax

OspA vax developed in 90’s but withdrawn