Lice

The three types of lice that affect humans are head lice, body lice, and pubic lice. These small parasitic insects feed on blood and have a life cycle of about one month. They can be transmitted in several ways, such as through direct contact with an infested person. The most common symptom of lice is itching, although some people with lice have no symptoms. Treatment options for a lice infestation include medication, nit picking, and treating the house.

 

What Are Lice?

Lice are small, wingless parasitic insects that feed on a human's blood. They can be found on various parts of the body, depending on the type of lice. Lice are most often spread through close contact with someone already infested with lice or through sharing personal belongings.
 
When a person is infested with lice (whether it is head lice, body lice, or pubic lice), the condition is known as pediculosis.
 

Types of Lice

The three kinds of lice that affect humans include:
 
  • Pediculus humanus capitis (head lice)
  • Pediculus humanus corporis (body lice)
  • Phthirus pubis (pubic lice or crab lice; also called crabs).
     
Each type of lice looks similar. They are very small (about 2 mm), flat, and wingless. They have three pairs of legs located directly behind the head. The legs end in sharp claws that are designed for feeding and allow for the louse to hold on tightly to hair or clothing. The head louse is the largest in size; the crab louse is the smallest.
 
(Lice Continued: Page 2)
Written by/reviewed by: Arthur Schoenstadt, MD
Last reviewed by: Arthur Schoenstadt, MD
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