Scabies

Question 1

What causes scabies?

Answer 1

The mite Sarcoptes scabiei

Question 2

How is scabies spread?

Answer 2

Prolonged skin contact

Question 3

What causes the itch in scabies?

Answer 3

Intense pruritus is associated with scabies due to a delayed type IV hypersensitivity reaction to mites/eggs which occurs about 30 days after the initial infection

Question 4

What are the features of scabies?

Answer 4

Widespread pruritus
Linear burrows on the hands
Infants: face and scalp
Scratching, excoriation and infection

Question 5

What is the management of scabies?

Answer 5

Permethrin 5%
Malathion 0.5%
Pruritus persists for up to 4-6 weeks post eradication

Question 6

What patient guidance should be given on the treatment of scabies?

Answer 6

Avoid close physical contact until treatment is complete
Household all treated
Launder, iron or tumble dry all laundry on the first day of treatment to kill off the mites.

Question 7

How should insecticide be applied in scabies?

Answer 7

To cool, dry skin.
All over
Leave for 8-12 hours before washing off, reapply if washed off
Repeat after 7 days.

Question 8

When might crusted (Norwegian) scabies occur?

Answer 8

In those with suppressed immunity, especially HIV.

Ivermectin is the treatment