Intro

Question 1

What bacteria causes rocky mountain spotted fever?

Answer 1

Rickettsia rickettsii

Question 2

What bacteria causes rickettsiapox?

Answer 2

R.Akari

Question 3

What bacteria causes epidemic typhus?

Answer 3

Rickettsia Prowazekii

Question 4

What baceria causes murine typhus?

Answer 4

Rickettsia Typhi

Question 5

What bacteria causes scrub typhus?

Answer 5

Orientia Tsutsugamushi

Question 6

What bacteria causes Ehrlichiosis

Answer 6

HME(human monocyte): E.Chaffeensis

HA(Human Anaplasmosis): A.Phagocytophlium, E.Ewingii

Question 7

What bacteria causes Q fever?

Answer 7

Coxiella Burnetii

Question 8

What are the general characteristics of these bacteria?

Answer 8

Obligate Intracellular
Transmitted by arthropods
clinical: fever, HA, rash

Question 9

What are the morphology of these bacteria

Answer 9

Small Gram Neg Rods (Giemsa stain)
LPS/peptidoglycan missing in some
No flagella

Question 10

Are these bacteria able to make their own ATP?

Answer 10

Yes
Early infection - use host
Later: use their own

Question 11

What kind of stain can be used to visualize these bacteria?

Answer 11

Giemsa; Stain poorly with gram stain

Question 12

Describe the pathogenesis of these bacteria?

Answer 12

Enter via endocytosis -> replicate in cytoplasmi vesicles or cytoplasm ->Exit via budding or lysis

Question 13

Which bacteria replicate in cytoplasmic vesicles?

Answer 13

Phagosome: Ehrlichia, Anaplasma

Phagolysosome like vesicle: Coxiella

Question 14

Which bacteria replicate in the cytoplasm?

Answer 14

Rickettsia

Orientia

Question 15

How do ehrlichia and anaplasm avoid killing by lysosomes?

Answer 15

Prevent fusion of phagosome with lysosome

Question 16

How does Coxiella prevent death from lysosomal fusion?

Answer 16

Prmotes delayed fusion with endosomes

Requires low pH for growth -> forms CCV (coxiella containing vesicle)

Question 17

How do rickettsia and orientia replicate in the cytoplasm?

Answer 17

Escape vesicle using phospholipase A -> multiplay in cytoplasm -> migrate intracellularly using actin polymerization -> can use this to transfer between 1 cell to neighboring cell without exposure to immune system

Question 18

Which ricketssia species does NOT use actin polymerization for migration intracellularly?

Answer 18

R.Prowazekii

Question 19

What is unique about coxiella compared to rickettsia, orientia, ehrlichia anaplasma?

Answer 19

It can survive outside of the host as ti is resistant to drying

Rickettsia, orientia, ehrlichia, and anaplasm are unstable and die rapidly

Question 20

Which disease are transmitted by ticks?

Answer 20

Rocky moutain spotted fever

Ehrlichiosis

Question 21

Which disese are transmitted by mites?

Answer 21

Rickettsialpox

Scrub Typhus

Question 22

Which disease are transmitted by lice?

Answer 22

Epidemic Typhus

Question 23

Which disease are transmitted by fleas?

Answer 23

Murine Typhus

Question 24

Which disease can be spread by aerosols from large mammals?

Answer 24

Q fever: Coxiella

Question 25

What is the primary lesion due to bacterial infeciton and multiplicaiton with these species?

Answer 25

Rash -> vasculitis in many organs

Question 26

How are diagnosis made for these bacteria?

Answer 26

Clinical findings + Epidemiologic information
Culturing is difficult and dangerous (obligate intracellular pathogens -> wont grow out in cultures in lab)

Serology: used to CONFIRM dx
IFA
MIF (microfluorescence assay)
PCR

Question 27

How do we treat these infections?

Answer 27

Therapy before seroconversion - treat before dx confirmation

Tx: Tetracyclines and Chloramphenicol => bacteriostatic

DON’T USE SULFONAMIDES -> ENHACES DISEASE

Question 28

Which diseases forms an eschar?

Answer 28

Rickettsialpox

Scrub Typhus

Question 29

Whcih disease have a gradual onset of sx?

Answer 29

Epidemic Typhus