Head Lice

Question 1

What is head lice also known as?

Answer 1

• pediculosis capitis

Question 2

What parasitic insect causes head lice?

Answer 2

• Pediculus humanus capitis

Question 3

What is the life cycle of head lice?

Answer 3

1. Louse eggs take 7-10 days to hatch
2. Immature lice (nymphs) take 7-10 days to mature into adults
3. Adult lice are up to 3 mm in length
4. female louse lays up to eight eggs per day
5. Transmission of head lice usually requires head-to-head contact
6. Can live for 30 days

Question 5

Which age group are commonly affected by head lice?

Answer 5

• 4-11
• peak age of 7-8 years

Question 6

What are the RF for head lice?

Answer 6

• Age less than 12 years.
• Female gender.
• Families with four or more children.
• Lower socio-economic status.
• Long hair

Question 7

What is the presentation of head lice?

Answer 7

• asymptomatic
• itching
• adult lice or nits have been seen
• live head louse is found - main diagnosis

Question 8

How would you catch head lice?

Answer 8

• Bug Buster® comb
• Wet combing
  
  • 10-15 minutes per head; lice are immobilised by hair conditioner, so are easy to see on the comb.
• Dry combing
  
  • 3-5 minutes per head. Using a comb on dry hair may produce static electricity; when a louse is spotted on the comb, placing a thumb on it before drawing the comb out of the hair prevents the louse being flicked off the comb by the static electricity in the hair.

Question 9

What are the differential diagnosis for head lice?

Answer 9

• Psychogenic itch
• eczema.
• Seborrhoeic scales
• Hair muffs
• Hair spray

Question 10

How would you mx head lice?

Answer 10

• General advice
  
  • Treat all affected household members simultaneously
  • no need to wash clothing or bedding that has been in contact with lice
• mechanical methods
  
  • wet combing
• physical insecticides
  
  • dimeticone
  • isopropyl myristate and cyclomethicone solution
• chemical or traditional insecticides
  
  • malathion 0.5% aqueous liquid (Derbac-M®)

Question 11

What are the cx of head lice?

Answer 11

• Pruritic rash on the back of the neck and behind the ears, caused by a hypersensitivity reaction to louse faeces.
• Excoriation, skin infection and impetigo may occasionally occur.
• Loss of sleep caused by continuous itching is occasionally a problem.
• Anxiety and distress for children and parents