Borrelia burgdorferi

Question 1

What does Borrelia cause?

Answer 1

Lyme disease

Question 2

What is the #1 bacterial infection in the world?

Answer 2

Lyme disease

Question 3

Borrelia general characteristics:

Answer 3

Spirochete

Inner &outer membrane

Fastidious

Gram - like, but not a true gram -

Linear chromosome, not circular + many linear and circular plasmids

Question 4

What are the requirements to grow Borrelia?

Answer 4

Grows in complex media @ 35 degrees Celsius

8hr generation time

Question 5

What Borrelia species cause Lyme disease?

Answer 5

B burgdorferi

B garinii

B afzelli

Question 6

What is characteristic of B burgdorferi genome?

Answer 6

It has a single small linear chromosome (not circular like the rest)

And has ~22 linear and circular plasmids

Question 7

____ ______ is the leading vecto-borne bacterial disease of humans in the world.

Answer 7

Lyme disease

Question 8

When and where was Lyme disease first described?

Answer 8

1975

In Lyme, Connecticut

Question 9

Lyme disease is a multi system illness that affects primarily the ____, __________, ______, and _____.

Answer 9

Skin

Nervous system

Heart

Joints

Question 10

Lyme disease is a zoonotic disease acquired from:

Answer 10

Deer tick vector (Ixodes sp.)

Mammalian host: white fitted mouse, rats, squirrels, etc)

Question 11

What is the number of annual cases of Lyme disease reported to the CDC?

Answer 11

30,000 cases

Question 12

How many stages does Lyme disease have?

Answer 12

At least 3 stages

Question 13

Where is Lyme disease common?

Answer 13

North hemisphere

Where there is a large population of the vector and reservoir

Question 14

Why is Lyme disease not common in Africa?

Answer 14

Lack of vector

Question 15

What are the early signs and symptoms of Lyme disease? (3-30. Days after bite)

Answer 15

Fever
Chills
Headache
Fatigue
Muscle/joint aches
Swollen lymph nodes
Sometimes rash

Question 16

Erythema migrants (EM) rash

Answer 16

Lyme disease related rash

Begins at site of bite after 3-30 days avg. 7 days

Expands gradually to reach up to 12in+ (30cm) across

May feel warm, not itchy or painful

Sometimes looks like a target as it enlarges

May appear on any area of body

Question 17

How many infected people get the EM rash?

Answer 17

70-80%

Question 18

Later signs of Lyme disease (days to months)

Answer 18

Severe headache and stiff neck

More EM rashes

Arthritis, severe joint pain, swelling in knees and large joints

Facial palsy

Intermittent pain in tendons, muscles, joints, and bones

Lyme carditis

Episodes of SOB/dizziness

Inflammation of brain/spinal cord

Nerve pain

Shooting pains, numbnesss, tingling in hands/feet

Short term memory problems

Question 19

What tick causes Lyme disease?

Answer 19

Ixodes scapularis

“Black-legged deer ticks”

Question 20

When do most symptoms of Lyme disease occur in humans?

Answer 20

Spring to summer

Question 21

Stages of Lyme disease

Answer 21

Stage 1: localized infection. Causes; EM rash, mild flu symptoms

Stage 2: disseminated infection. Transient blood borne phase. Causes colonization of diverse tissues if no treatment

Stage 3: late stage. Long-term survival of B burg. -arthritis, Lyme encephalopathy, acrodermitis chronic atrophicans (skin) not common b/c treatment

Question 22

Virulence factors of Borrelia causing Lyme disease

Answer 22

Outer membrane proteins: OspA, OspC

Peptidoglycan..endotoxin

Question 23

Diagnosis of Lyme disease

Answer 23

Clinical diagnosis

Bacterial cultures

PCR based assay

Serological assays

Question 24

Treatment of Lyme disease

Answer 24

Doxycycline, amoxicillin, 3rd generation cephalosporin drugs

Oral or could be intravenous

Treatment could last 3-4 weeks

Question 25

Best prevention for Lyme disease

Answer 25

Behavioral: bug spray, layers of clothing, checking for ticks

Question 26

Withdrawn prevention of Lyme disease

Answer 26

Vaccine based on OspA

Question 27

What is another I’mportant spirochete disease?

Answer 27

Syphilis

3rd most common bacterial disease

Treat w/ penicillin
3 stages, late stage not common