Other Zoonotic or Vector Borne diseases

Question 1

francisella tularensis

Answer 1

causes rabbit fever/tularemia/glandular fever

Gram neg rod that grows in macrophages, cysteine-supplemented media required

vector is hard tick or contact with infected rabbit

VERY infectious –> low infectious dose

at risk: hunters, vets, lab workers

Question 2

Answer 2

francisella tularensis

small gram - coccobaccilus/rod

grows in macrophages

causes tularemia/rabbit fever/glandular fever

Question 3

different tularemia infections

Answer 3

Ulceroglandular tularemia - d/t primary infection of the skin

-skin ulcer (animal/insect bite), Swollen and painful LNs, fevers, chills

Oculoglandular tularemia - affects the eyes/conjunctiva

• Eye pain, redness, swelling, eyelid ulcer, light sensitivity

Pneumonic tularemia - resembles pneumonia; aerosol transmission or spread to lungs

-Dry cough, Chest pain, Difficulty breathing

Typhoidal tularemia - d/t ingestion

-High fever, exhaustion, N/V/D, hepatosplenomegaly, Pneumonia

Question 4

culture medium for tularemia requires

Answer 4

cysteine

Question 5

brucella species

Answer 5

intracellular parasites of the RES in humans

no vector!!, genitourinary pathogen in animals –> shed in milk

-acquired by infected milk or contact with cattle, sheep, pigs, goats

causes brucellosis (undulant fever)

Question 6

increased risk factors for brucellosis

Answer 6

• slaughterhouse workers and meat-packing
• vets/lab workers/hunters

and

UNpasteurized cheeses (tourists!!!)

Question 7

pathogenesis of brucellosis

Answer 7

multiplies in macrophages and phagocytic cells of the RES

creates granulomas with recurrent bacteremia

Question 8

chronic brucellosis (undulant fever) symptoms

Answer 8

Incubation period: 2- 8 weeks

Fever, night sweats, headaches, chills, myalagia, weight loss

Organs of the RES often NOT enlarged

Complications = hepatic lesions, arthritis, meningitis, and endocarditis

Question 9

bartonella diseases and their vectors

Answer 9

bartonella henselae (cat scratch) = flea

bartonella quintana (trench fever) = lice

bartonella bacilliformis (carrions disease) = sand fly

Question 10

cat scratch disease

Answer 10

bartonella henselae

cat flea is vector

in immuno competent –> catscratch disease (inflammation)

in immuno compromised –> bacillar angiomatosis (erythrocyte and endothelial colonization)

Question 11

Answer 11

bacillary angiomatosis

due to bartonella

Question 12

trench fever

Answer 12

caused by bartonella quintana

vector is lice; human reservoir

5 days of fever (febrile bacteremia) in immuno competent

immunocompromised –> bacillary angiomatosis and endocarditis

Question 13

bartonellosis by nartonella bacilliformis

Answer 13

vector is sandfly; human reservoir

causes Biphasic disease –> carrions disease

1st phase = oroya fever (hemolytic anemia)

2nd phase = verruga peruana (blood filled/purple warts)

Question 14

treatment for cat scratch disease?

Answer 14

azithromycin

Question 15

rickettsiaceae bacteria

Answer 15

obligate intracellular bacteria that are usually transmitted by arthropods

gram -coccobacilli; visible with giemsa stain

2 types - rickettsia and orientia.

Question 16

R. Rickettsii causes….

Answer 16

RMSF rocky mtn spotted fever

vector = ticks

Question 17

spread of rickettsia from cell to cell involves….

Answer 17

actin polymerization

Question 18

pathogenesis of spotted fever and typhus (rickettsiaceae)

Answer 18

vasculitis!!

caused by proliferation of the organisms in the endothelial lining of small vessels

vascular lesions in skin are prominent

Question 19

rickettsia rickettsii

Answer 19

cause of RMSF

tick borne

Question 20

tick vector in the west

tick vector in the east

tick vector in part of arizona

Answer 20

west = dermacator andersonii

east = dermacator verabilis

az = rhipicephalus sanguineus

Question 21

Answer 21

rocky mountain spotted fever

d/t R. rickettsii

Question 22

best treatment for rickettsial infections including RMSF?

Answer 22

doxycycline

Question 23

rickettsia akara

Answer 23

Cause of rickettsial pox

mite-borne (rodent –> mite –> human)

occurs in USA and everywhere.

Rash more like that of chicken pox (papulovesicular); Eschar at site of mite bite (mimics cutaneous anthrax)

Question 24

rickettsia prowazekii

Answer 24

cause of epidemic typhus

Body louse

not in USA; in places of war (Somalia)

Question 25

rickettsia typhi

Answer 25

Cause of endemic or murine typhus

disease occurs worldwide to include USA (Gulf Coast area)

flea-borne; rodent vectors

Question 26

ehrlichia and anaplasma

Answer 26

obligate intracellular bacteria that survive in cytoplasmic vacuoles of mammalian hematopoetic cells

(in contrast to Rickettsia and Orientia that live in endothelial cells)

Question 27

Rickettsia and Orientia

vs

ehrlichia and anaplasma

Answer 27

R/O – live in endothelial cells

E/A - live in cytoplasmic vacuoles of mamal hematopoetic cells

Question 28

lone star tick is geographically located

Answer 28

south east US

Question 29

anaplasma phagocytophilum

Answer 29

primarily infects granulocytes (neutrophils and rarely eosinophils).

The pathogen is often referred to as the agent of HGE.

Transmitted by Ixodes scapularis -can co-transmit the agent of Lyme disease, Borrellia burgdorferi

Question 30

coxiella burnetii

Answer 30

humans infected through contact with cattle, goats, sheep

ticks probably important in animal to animal transmission

flu like illness (Q fever) –> atypical pneumonia; rarely endocarditis

Question 31

Ticks cause….(8)

Mites cause…(2)

Lice cause…(3)

Fleas cause… (4)

Answer 31

Ticks-Lyme disease, HGE, HME, STARI, endemic relapsing fever, RMSF and sometimes tularemia and Q fever

Mites-Scrub typhus, Rickettsialpox

Lice-Trench fever, epidemic typhus, epidemic relapsing fever

Fleas- endemic typhus (=murine typhus), murine typhus like, bubonic plague, cat scratch fever

Question 32

characteristics of ticks that make them high potential vectors

Answer 32

• Persistent bloodsuckers - attach firmly
• Slow feeding - allows wide dispersion
• Highly sclerotized - resistant to environmental stresses
• Relatively free from natural enemies
• Wide host range - certain source of blood
• Longevity - may live 14 years or more (soft ticks)
• Transovarian transmission - pass infection onto progeny
• Reproductive potential - may deposit up to 18,000 eggs