Dr.Lacount - Lice and Pinworms - 2 Q

Question 1

Be able to describe how lice is transmitted, and which populations are most
frequently infected.

Answer 1

Pediculosis (lice) - spread through direct contact mainly occurring in children

Pinworm: Helminth infections: Spread from walking bare foot outside, can come from food, Pre-school and school aged children tend to have higher burdens of intestinal worms and schistosomes

Question 2

Be able to describe how pinworms are transmitted, and which populations are most frequently infected.

Answer 2

Entorobiasis (pinworm infection): most common in school age children, institutionalized persons, household members or caretakers, fecal-oral transmission

Pinworm: Helminth infections: Spread from walking bare foot outside, can come from food, Pre-school and school aged children tend to have higher burdens of intestinal worms and schistosomes

Question 3

Be able to describe the symptoms of lice and pinworms infections

Answer 3

Lice: Itching

Pinworm: stunted growth, diminished physical fitness, impaired memory and cognition leading to education deficits

Question 4

Be able to describe the spectrum of activity, mechanism of action, and basis for
specificity (if known) of the following antiparasitic drugs:

Pyrethrin and pyrethroid

Answer 4

MOA: nerve membrane sodium channel toxins that do not affect potassium channels

Question 5

Be able to describe the spectrum of activity, mechanism of action, and basis for
specificity (if known) of the following antiparasitic drugs:
Spinosad

Answer 5

MOA: nicotinic acetylcholine receptor agonist leads to killing of live lice and unhatched eggs

Question 6

Be able to describe the spectrum of activity, mechanism of action, and basis for
specificity (if known) of the following antiparasitic drugs:

Albendazole and Mebendazole

Answer 6

Mechanism of action
- Binds to tubulin
- Inhibits formation of microtubules
-Microtubules grow from “plus” end
-Benzimidazoles cap microtubules
-Microtubules continue to be shortened from minus end
Inhibits cell division, secretion of parasite molecules,
glucose uptake

• Can bind to mammalian tubulin
• Binds with higher affinity to helminth tubulin

Question 7

Be able to describe the spectrum of activity, mechanism of action, and basis for
specificity (if known) of the following antiparasitic drugs:

Pyrantel pamoate

Answer 7

Depolarizing Neuromuscular blocking agent
Ø Causes release of acetylcholine and inhibition of
cholinesterase
Ø Worms are paralyzed & expelled