Vector-borne and zoonotic bacterial infections

Question 1

Rickettsia species causes

Answer 1

Spotted fevers and typhus

Question 2

Erlichia chaffeensis causes

Answer 2

Human monocytic ehrlichiosis

Question 3

Anaplasma phagocytophilum causes

Answer 3

Anaplasmosis

Question 4

Borrelia burgdorferi causes

Answer 4

Lyme disease

Question 5

What does borrelia burdorferi look like?

Answer 5

Spirochete, hard to visualize with gram stain because it’s so small.

Question 6

Lyme disease rash called

Answer 6

Bulls eye or erythema migrans

Question 7

Can lyme disease affect the heart?

Answer 7

Yes causes heart block.

Question 8

What is the vector for B. burgdorferi?

Answer 8

Ixodes scapularis (blacklegged tick).

Question 9

Where is B. burgdorferi common?

Answer 9

Northeast

Question 10

Reservoir for burgdorferi?

Answer 10

White footed mice, which are bitten by Ixodes scapularis

Question 11

Why are deer significant in lyme disease?

Answer 11

Because they keep adult ticks (that are carrying Borrelia burgdorferi) alive

Question 12

What stage of ixode development is most significant for causing disease?

Answer 12

Nymph

Question 13

Phases of lyme disease

Answer 13

Early localized: characterized by erythemia migrans and mild systemic symptoms (fever, chills).

Early disseminated: Meningitis, Bell’s Palsy, heart block, rash.

Late disease: Arthritis on knees, chronic neurological problems

Question 14

How to diagnose?

Answer 14

Clinical picture, IgG and IgM antibody tests.

Question 15

How to treat lyme disease

Answer 15

Oral doxycycline (amoxicillin in children), or if it gets serious, cefriaxone.

Question 16

Leptospirosis caused by

Answer 16

Leptospira species. Comes from raccoon urine that is picked up by dogs, can be transmitted to humans.

Question 17

Diagnosis of leptospirosis?

Answer 17

Serology, look for serum antibodies

Question 18

Treatment of leptospirosis

Answer 18

Penicillin

Question 19

Symptoms of leptospirosis

Answer 19

Hematogenous spread causing fever and headache. Then full blown disease occurs causing meningitis, nephritis, hepatitis, rash.

Question 20

Rickettsia Rickettsii causes

Answer 20

Rocky Mountain Spotted Fever

Question 21

Rickettsia Rickettsii gram stain?

Answer 21

None.

Question 22

Reservoir?

Answer 22

Hard ticks, also the vector

Question 23

Why is it so important?

Answer 23

23% mortality

Question 24

How is R. rickettsii pathogenic?

Answer 24

Obligate intracellular organism

Question 25

Where does R. rickettsii occur?

Answer 25

Southeast

Question 26

What are the symptoms of rocky mountain spotted fever?

Answer 26

Fever, headache, spotted rash.

Question 27

How does R. rickettsii enter the cell?

Answer 27

At endothelial cell! Induces its own phagocytosis, releases phospholipase to escape from the phagosome and propels itself by using host cell actin.

Question 28

Ehrlichiosis caused by?

Answer 28

Ehrlichia chaffeensis

Question 29

What happens in ehrlichiosis?

Answer 29

Monocytes are invaded

Question 30

What causes anaplasmosis?

Answer 30

Anaplasma phagocytophilium

Question 31

What happens in anaplasmosis?

Answer 31

Granulocytes invaded.

Question 32

Where do ehrlichiosis and anaplasmosis occur?

Answer 32

E: Southeast
A: Northeast

Question 33

How to treat rickettsia, ehrlichiosis, and anaplasmosis?

Answer 33

Immediate doxycycline.