Borrelia

Question 1

Physical description of Borrelia

Answer 1

• long spirochete
• G negative
• no LPS
• inflammatory proteins in O.M. (OspA, OspC)

Question 2

Known types of Borrelia

Answer 2

• B. recurrentis, B. hermsii and others: relapsing fever

- B. burgdorferi and others: Lyme disease

Question 3

Clinical presentation of B. recurrentis and B. hermsii

Answer 3

• general bacteremia within 1 week of inoculation
• sudden onset of fever, intense headache, muscle pain
• subsides in 3-5days
• symptoms recur after 5-10days latency
• recurrence caused by antigenic variation

Question 4

Clinical presentation of B. burgdorferi

Answer 4

• early symptoms flu like; fever, headache, myalgia
• early localized disease includes bulls eye rash
• erythema chronicum migrants lead to; facial nerve palsy, meningitis, carditis
• chronic infection; arthritis, joint pain, nerves and heart affected

Question 5

Epidemiology of B. recurrentis

Answer 5

• spread by human louse from human reservoir

- inoculated when louse is scratched into skin

Question 6

Epidemiology of B. hermsii

Answer 6

• spread by soft bodied ticks from rodent reservoir
• transovarian cycle in the tick
• many infected ticks in W. US

Question 7

Epidemiology of B. burgdorferi

Answer 7

• spread by deer tick lymph from deer, mouse, bird reservoir

- NE and upper Midwest

Question 8

Pathogenesis of B. recurrentis and B. hermsii

Answer 8

• main virulence factor is antigenic variation
• VMP protein antigen
• most population has one
• host Abs act as a selective agents
• latency is when most of population has been killed
• relapse when mutant variety grows to repopulate

Question 9

Pathogenesis of B. burgdorferi

Answer 9

• does NOT undergo antigenic variation

- multiple rounds of symptoms, second infection with different strain

Question 10

Control of Borrelia

Answer 10

• avoid vectors; hygienic delousing and clothing
• Doxycycline or synthetic penicillins to treat
• 3rd generation cephalosporins for recurrent