Ectoparasitic Infections 🦟

Question 1

What is the incubation period for Crusted (Norwegian) Scabies

Answer 1

one month!

Question 2

Scabies infection first time = itchy in ____ (timeframe)

Scabies infection reinfection = itching in _____(timeframe)

Answer 2

first time = weeks to develop

reinfection = 24 hours

Question 3

Flea bite or scabies??

concentrated in the lower extremities like feet, legs

Answer 3

flea bites

Question 4

How is pubic lice transmitted

Answer 4

sexual contact

contaminated bedding

Question 5

Symptoms of Rocky Mountain spotted fever

Answer 5

2-14 days after tick bite

SUDDEN ONSET of fever and headache*
RASH* (2 types)

N/V, abd pain, lack of appetite, etc.

Question 6

How does Pulex irritans (human flea) attach to the host

Answer 6

short spike on legs allow attachment

Question 7

Phthirus pubis - the nits can be found _____ and the adults can be found ______

Answer 7

nits = cemented to hair

adults = bite and feed in pubic area

Question 8

Rickettsia rickettsii =

gram (+/-)
motile?
shape?
type of pathogen?

Answer 8

gram negative

non-motile

pleomorphic

OBLIGATE INTRACELLULAR***

Question 9

What is the species for pubic lice “crabs”

Answer 9

Phthirus pubis

Question 10

Flea bite or scabies??

raised bumps or halo surrounding the actual bite site

Answer 10

flea bites

Question 11

What are the two types of rash in rocky mountain spotted fever

Answer 11

1. small flat PINK non itchy spots on wrists, forearms, and ankles that spreads to trunk, Palms* and Soles* (2-5 days after infection).
2. RED to purple spotted petechial rash, pinpoint hemorrhages.Sign of late and severe disease(6 days after infection)

Question 12

Where do female Sarcoptes scabiei go on the skin?

Where do male Sarcoptes scabiei go on the skin?

Answer 12

female = burrows into epidermis, 5 week life span, dies in burrow

male = remains on skin surface/ or shallow burrow

Question 13

How do identify scabies

Answer 13

apply mineral oil

scrape lesion

visualize microscopically - look for whole mites or mite parts, eggs or fecal pellets in burrows

Question 14

What is “vagabond’s disease”

Answer 14

years of infestation of pediculus humanus

bite irritation - blood sucking parasite

darkened, thickened skin

Question 15

What type of scabies is often seen in HIV patients

Answer 15

Crusted (Norwegian) Scabies

Question 16

Burrowing mite that is the most serious of the mites

Answer 16

Sarcoptes scabiei

Question 17

What are the 3 ticks that are arthropod vectors for rocky mountain spotted fever (Rickettsia rickettsii)

Answer 17

American dog tick

Rocky mountain wood tick

Brown dog tick

Question 18

What is the life cycle of Sarcoptes scabiei

Answer 18

eggs laid under the skin

larva emerges from the eggs after 5 days of incubation

adult mite develops 2 weeks after hatching

Question 19

intensely pruritic eruption that is worse at night

Answer 19

Sarcoptes scabiei

Question 20

Flea bite or scabies??

pimple like rash that leads to intense itching at night

Answer 20

scabies

Question 21

“small mite with short legs” **

Answer 21

Sarcoptes scabiei

Question 22

Flea bite or scabies??

do not live on humans- prefer pet hair

Answer 22

flea bites

Question 23

ectoparasite bigger than Sarcoptes scabiei with LONG LEGS*

Answer 23

Phthirus pubis

Question 24

What type of scabies is similar to Crusted (Norwegian) Scabies but lesions are BLOOD-FILLED

Answer 24

pediatric scabies

Question 25

Flea bite or scabies?? can spread from skin-to skin contact

Answer 25

scabies

Question 26

Flea bite or scabies?? can occur anywhere on the body including the web of the skin between fingers and toes, folds of the wrists, on the waist, under the breasts or genitals

Answer 26

scabies

Question 27

Flea bite or scabies?? not contagious

Answer 27

flea bites

Question 28

Flea bite or scabies?? capable of jumping long distances

Answer 28

flea bites

Question 29

Flea bite or scabies?? appear in a tunnel or burrow like rash beneath the skin

Answer 29

scabies

Question 30

How does Rickettsia Rickettsii infect the body?

Answer 30

painless bite invades ENDOTHELIAL CELLS THAT LINE BLOOD VESSELS*********

Question 31

Flea bite or scabies?? live on human skin and even lay eggs beneath it

Answer 31

scabies

Question 32

Flea bite or scabies?? cannot jump nor fly. crawl very slowly

Answer 32

scabies

Question 33

What is the gold standard for diagnosing Rickettsia Rickettsii

Answer 33

indirect immunofluorescence with a R. rickettsii antigen 2 samples 2-4 weeks apart (dx tests are not good! most dx is clinical!)

Question 34

Flea bite or scabies?? groups of three or four, generally in a LINEAR pattern

Answer 34

flea bites

Question 35

Flea bite or scabies?? anyone can get bites

Answer 35

flea bites

Question 36

How is scabies transmitted?

Answer 36

direct person contact usually an STI in adults found in crowded living conditions (LIKE A NAVY BASE WHERE I GOT THIS GROSS ASS THING)

Question 37

What is the main manifestation of Pulex irritan (human flea) infestation

Answer 37

RASH during blood meal, injects saliva that initiates allergic response

Question 38

What do Pulex irrians (human flea) ABSOLUTELY need to survive

Answer 38

BLOOD BLOOD BLOOOOOOOD

Question 39

ectoparasite that is MUCH MUCH bigger than Phthirus pubis and Sarcoptes scabiei

Answer 39

Pediculus humanus (head lice)

Question 40

Flea bite or scabies?? more common in children and elderly

Answer 40

scabies

Question 41

What is responsible for rocky mountain spotted fever in Arizona

Answer 41

brown dog tick

Question 42

What time of year does Rocky mountain spotted fever appear in Arizona?

Answer 42

April to October peaks in June and July