Zoonotic Infections

Question 1

What is Rickettsia?

Answer 1

Gram-negative rod, obligate intracellular bacteria. Vector borne.

Question 2

What is classic presentation of Rickettsia?

Answer 2

fever-headache-rash

Question 3

Where do rickettsia replicate?

Answer 3

in cytoplasm of endothelial and muscle cells of small blood vessels

Question 4

What disease does R. rickettsia cause? What are its presentations?

Answer 4

Rocky Mountain Spotted Fever. Flu symptoms withere severe headache and a rash that spreads from ankles and wrists to soles, palms and trunk. Muscle pain (especially calf)

Question 5

How is RMSF diagnosed?

Answer 5

Weil-Felix test and confirmed by convalescent sera.

Question 6

What does Weil-Felix test for?

Answer 6

measures cross-reactivity of anti-rickettsial antibodies to Proteus OX strains.

Question 7

What is treatment for RMSF?

Answer 7

doxy

Question 8

What disease does R. prowazekii cause?

Answer 8

epidemic typhus. Rash spreads from trunk to extremities (opposite of RMSF). Flying squirrels?

Question 9

How is R. prowazekki transmitted?

Answer 9

human-to-human via body lice (not a zoonosis)

Question 10

How is erhlichia transmitted?

Answer 10

by ticks

Question 11

How does erhlichia replicate?

Answer 11

intracellular in white blood cells.
E. chaffeensis - monocytes
A. phagocytophilia - granulocytes

Question 12

Would a Weil-Felix reaction be positive or negative for Ehrlichia?

Answer 12

negative

Question 13

How do you diagnose E. chaffeensis?

Answer 13

Wright/Giemsa stain of blood smear. Look for morulae in MONOCYTES

Question 14

What causes Rocky Mtn. SpotLESS fever?

Answer 14

A. phagocytophilia.

Question 15

How is A. phagocytophilia infection diagnosed?

Answer 15

wright/giemsa stain of blood smear. morulae in GRANULOCYTES

Question 16

What is the cause of Lyme Disease?

Answer 16

B. burgdorferi

Question 17

How is B. burgdorferi transmitted?

Answer 17

nyph Ioxodes deer ticks

Question 18

What are the three stages of LD?

Answer 18

Early - flu-like, bulls eye rash
Disseminated - arthritis, facial palsy, peripheral neuropathy
Chronic - erosive arthritis in knees, numbness, bell palsy

Question 19

How is B. burgdorferi infection diagnosed?

Answer 19

Two step serology: ELISA then Western Blot

Question 20

How is LD treated?

Answer 20

doxy

Question 21

What causes relapsing fever?

Answer 21

B. hermsii or B. recurrentis

Question 22

How is B. hermsii transmitted? B. recurrentis?

Answer 22

hermsi by tick

recurrentis by louse

Question 23

How is relapsing fever caused by B. hermsi treated?

Answer 23

doxy

Question 24

How is leptrospira interrogans contracted?

Answer 24

contact with urine contaminated water in broken skin.

Question 25

What are the symptoms of leptrospira?

Answer 25

Flue, jaundice and renal damage (Weil’s disease), meningitis. NO SKIN LESIONS

Question 26

What is the treatment of leptrospira?

Answer 26

penicillin

Question 27

What is the cause of cat-scratch fever?

Answer 27

Bartonella henselae

Question 28

What is presentation of Bartonella henselae infection?

Answer 28

mostly seen in peds, which have swollen lymphs near scratch. Adults have flu symptoms

Question 29

What would cause eschar at site of infection?

Answer 29

anthrax

Question 30

What would cause swollen glands in groin or axilla?

Answer 30

bubos from plague

Question 31

What would cause ulcer at site of infection?

Answer 31

tularemia

Question 32

How is R. typhi spread?

Answer 32

transmitted to humans by rat flea

Question 33

What disease does R. typhi cause?

Answer 33

endemic (murine) typhus

Question 34

What is more severe: epidemic or endemic typhus?

Answer 34

epidemic typhus more severe

Question 35

What do morulae in monocytes indicate?

Answer 35

E. chafeensis

Question 36

What transmits the bug that produces morulae in human granulocytes?

Answer 36

A. phagocytophilia (rocky mtn spotless fever) is transmitted by ixodes deer ticks