Other Zoonotic & Vector-Borne Diseases

Question 1

Zoonoses

Answer 1

Infections normally found in nonhuman vertebrates that are

transmitted to humans

Question 2

Franciscella tularensis

Answer 2

“Rabits eat tulips”

Rabit fever

Tularemia = ulcers at the site of infection, fever, and weight loss

Glandular fever (think EBV/mono fever)

Question 3

Small gram (-)

coccobacilli

stains poorly

Faculatative intracellular

Requires cysteine

Answer 3

Franciscella tularensis

Question 4

Transmission of Franciscella tularensis

Answer 4

Highly infectious (alert lab before sending sample for serology)

Hard Tick bites, Exposure to mucous membranes, Aerosol (has been used as germ-warfare), Ingestion

Question 5

Diseases transmitted by hard ticks

Answer 5

Lyme disease

Rocky Mountain spotted fever

Tularemia

Colorado tick fever

Human tick-borne ehrlichiosis

American babesiosis

Tick paralysis

STARI (Southern tick-associated rash illness)

Anaplasmosis

Question 6

Diseases transmitted by soft ticks

Answer 6

Tick-borne relapsing fever

Question 7

Types of infections with Franciscella tularensis

Answer 7

Ulceroglandular (most common, skin)

Oculoglandular

Pneumonic (30% fatal)

Typhoidal (ingestion)

Question 8

Why is Franciscella tularensis a good biological weapon?

Answer 8

Low infectious dose

Severe disease

Airborn transmission

Question 9

Who is at risk for Franciscella tularensis

Answer 9

Rabit hunters

Kids who run over rabits while mowing the lawn

Lab workers

Veterinarians

Question 10

Undulant fever after drinking unpasteurized milk

Answer 10

Brucella suis

Question 11

Brucella suis

Answer 11

Humans: facultative intracellular parasites of RES

Animals: GU pathogens shed in milk (no vector)

Enter via mucous membranes, skin, ingestion/inhalation; engulfed by PMNs and macrophages; travel to regional lymph nodes; multiply in macrophages; phagocyctic cells of RES; killed by phagocytic cells or contained within granulomas (prone to recurrent bacteremia)

Question 12

Which profession is most at risk for acquiring Brucella suis?

Answer 12

Lab workers

Question 13

Complications of Brucella suis

Answer 13

Fever, night sweats, headache, chills, myalgias, and weight loss

Hepatic lesions, arthritis, meningitis, endocarditis

Question 14

Lymphadenopathy + new kitten

Answer 14

Bartonella henselae (flea vector)

Question 15

Trench fever + Vector

Answer 15

Bartonella quintana (body louse)

Question 16

Carrion’s disease

Answer 16

Limited to the Andes (Peru)

Bartonella bacilliformis (sand fly vector)

1st phase: Oroya fever (hemolytic anemia)

2nd phase: Verruga peruana (Peruvian warts)

Question 17

Febrile bacteremia

Answer 17

Trench Fever (5 day fever)

Bartonella quintana

Immunocompromised = bacillary angiomatosis + endocarditis

Question 18

Girl scratched by cat

Two-week history of swelling behind her ear

Diagnosis/confirmatory test/treatment?

Answer 18

Bartonella henselae

Serologic analysis

Lymph node drainage + azithromycin

Question 19

Vector for brucella?

Answer 19

Does not have one

Question 20

Can grow on artificial media

Found in RBCs

Answer 20

Bartonella

Question 21

Obligate intracellular bacteria

Transmitted by arthropods

Answer 21

Rickettsiaceae

Question 22

Tick-borne Rickettsia

Answer 22

Rickettsia rickettssii (RMSF)

Question 23

Mite-borne Rickettsia

Answer 23

Rickettsia akari (Rickettsialpox)

Orientia tsutsugamushi (scrub typhus)

Question 24

Louse-borne Rickettsia

Answer 24

Rickettsia prowasekii (epidemic typhus)

Question 25

Flea-borne Rickettsia

Answer 25

Rickettsia typhi (murine endemic typhus)

Question 26

Gram - coccobacilli Requires host cell for many functions Movement from cell to cell involves actin polymerization

Answer 26

Rickettsia

Question 27

Pathogenesis of Spotted Fever and Typhus (the two groups of Rickettsia)

Answer 27

Vasculitis Proliferation of the organisms in the endothelial lining of small arteries, veins, capillaries Skin rash + Severe headache

Question 28

EM slide with comet-like tail

Answer 28

Rickettsia Do not confuse with comet-tail from ultrasound (pulmonary edema)

Question 29

Which age group is most susceptible to RMSF (Rickettsia rickettssii)?

Answer 29

Age 0-9 are 5x more likely

Question 30

Most effective treatment for RMSF

Answer 30

Doxy Common misperceptions about side effects. Short courses = no problems with tooth staining or weakening of enamel

Question 31

Rash that looks like chicken pox Eschar at site of bite

Answer 31

Rickettsia akari *Do not confuse this eschar with that of anthrax*

Question 32

Rickettsia prowazekii

Answer 32

***P**r**owa**zekki* ***P**laces **o**f **wa**r (Somalia)* Causes epidemic typhus Typhus means "smoky/hazy" (describing complications in the mind) Signs of meningoencephalitis begin with the rash and continue into the 2nd or 3rd weeks. Other signs of meningoencephalitis include sensitivity to light or photophobia, delirium or altered mental status, or coma

Question 33

Military importance in Vietnam

Answer 33

Orienta tsutsugamushi aka Scrub typhus

Question 34

Rickettsia typhi

Answer 34

Murine/Endemic typhus Form of typhus transmitted by fleas (Xenopsylla cheopis), usually on rats

Question 35

Obligate intracellular Survive in cytoplasmic vacuoles of mammalian **hematopoetic cells**

Answer 35

**Anaplasmataceae (Anaplasma & Ehrlichia)** *Contrast with Rickettsia/Orienta that live in endothelial cells*

Question 36

Transmitted by the lone star tick Inclusions in monocytes/macrophages Headache, Muscle Ache, Fatigue

Answer 36

Ehrlichia chaffeensis (HME)

Question 37

What does Ehrlichia chaffeensis (HME) do?

Answer 37

Blunts the immune system, allowing opportunistic infections to take over

Question 38

Inclusions in granulocytes Transmitted by Ixodes tick

Answer 38

Anaplasma phagocytophilum

Question 39

Transmitted via tick feces or cattle placenta Flu-like symptoms Diffuse perspiration

Answer 39

Q fever Coxiella burnetti

Question 40

Other complications of Coxiella burnetti

Answer 40

Atypical pneumonia Rarely, endocarditis Can occur decades after initial infection

Question 41

Any question that mentions armadillos

Answer 41

Mycobacterium leprae