Lice are blood-sucking insects and specific parasites of human beings; pubic lice are slightly smaller than head lice and body lice

Aetiology

• Acquired by close genital skin contact

Pathophysiology

• Lice bite skin and feed on blood, which causes itching in pubic area
• Female louse lays eggs on hair next to skin
• Males on average live for 22 days, females for 17 days

Clinical features

• Itchy red papules are the most common presentation
  • Itching takes 1-3 weeks to develop after the first infestation but may occur immediately following re-infestation
  • Itching tends to be worse at night
• Blue macules may be visible at feeding sites
• Minute dark-brown specks of louse excreta are sometimes seen on the skin and underwear

Investigations

• The diagnosis is based on finding adult lice or eggs

Management

• Two applications of malathion 0.5% aqueous lotion or permethrin 5% dermal cream, seven days apart