Arthropods

Question 1

vector

Answer 1

transfer pathogen between hosts

mechanical or biological

Question 2

mechanical vector

Answer 2

moves pathogen from one location to another
not required for pathogen development
spread diarrheal diseases
flies, roaches

Question 3

biological vector

Answer 3

life cycle stages of pathogen occur in vector

mosquito, lice, ticks

Question 4

resorvoir

Answer 4

organism maintains pathogen in nature

usually mammal or bird

Question 5

transovarial transmission

Answer 5

all stages of vector infected
passed from adult directly into arthropod eggs
ticks (Rickettsia prowazekii)

Question 6

Ricketsia prowazekii

Answer 6

cause of typhus
vector- body louse
louse bites and defacates into wound

Question 7

Florence Nightengale

Answer 7

recognized cleanliness would eliminate typhus

Question 8

Anne Frank

Answer 8

died of typhus in a concentration camp

Question 9

Yersinia pestis

Answer 9

bubonic plague
vector- oriental rat flea
reservoir- wild rodents
Yersinia blocks the fleas digestive tract and the flea is starved
urban rats die when infected and the fleas start feeding on humans
lymph nodes swell- bubo
pneumonic plague- lungs, most virulent
low infection dose- 30 to 50 cells

Question 10

ticks

Answer 10

larvae- hatch from eggs and feed on infected rodents
nymph- feed on any vertebrae
adult- feeds on deer and rodents
2-3 year life cycle
requires 3 blood meals

Question 11

Rickettsia rickettsii

Answer 11

Rocky Mountain spotted fever
transmitted by dog, wood and Lone Star ticks
transovarial
symptoms- chills, fever, headache, muscle pain

Question 12

Borrelia burgdorferi

Answer 12

Lyme disease
Ixodes tick
requires different mammalian reservoirs- field mice or deer

Question 13

yellow fever

Answer 13

human reservoir
Aedes aegyptii mosquito vector
skin to lymph nodes to liver
causes jaundice
high mortality
Walter Reed proved is was spread by mosquito

Question 14

jungle yellow fever

Answer 14

monkey reservoir

Question 15

West Nile virus

Answer 15

horses and birds are the normal reservoir- humans accidentally infected
encephilitis

Question 16

Dengue fever

Answer 16

hemorraghic
Aedes mosquitos vector
unknown reservoir
"breakbone" fever
endemic in Caribbean

Question 17

scabies

Answer 17

Sarcoptes scabiei