Pediculosis: Definition, Symptoms & Treatment

Instructor: Marisela Duque

Marisela teaches nursing courses at the college level. She also works as a unit educator, teaching experienced nurses about changes in nursing practice.

After completing this lesson, you will be able to define pediculosis and describe the symptoms and treatment for this condition. A short quiz follows this lesson.

You Are Surrounded!

It's every parent's worst fear to hear that one of their child's classmates has head lice. Those creepy little bugs are probably all over your kid's hair, on their clothes, or in their backpack. Then you wonder if they've already invaded your home, examining every speck of dust as a potential intruder. Suddenly you notice the dog scratching himself more than usual, he probably has some, too. Then the unthinkable happens, you start to itch and you know that you are surrounded! Not even your dreams are safe, they are filled with human-size bugs building nests and sipping Bloody Marys, oblivious to your suffering. Is there no end to this madness?

While this may seem like a scene from a scary movie, pediculosis which is the medical term for a lice infestation, is a very real, very annoying condition that can drive anyone mad. Luckily, there are remedies that can help you reclaim your sanity.

Defining Pediculosis

The term pediculosis comes from the Latin word pediculus, meaning louse. Lice are white or reddish-brown bugs that are about 1-3 mm long.The three species of lice that affect people are head lice - Pediculus humanus capitis, pubic lice - Phthirus pubis, and body lice - Pediculus humanus corpus. Lice crawl onto you and lay egg nests, called nits, that stick to your hair or clothes. These nits hatch and create an infestation which is extremely itchy for the host. Lice are found all over the world and survive by drinking human blood several times a day

Lice do not hop or fly, they spread by close physical contact or by sharing clothes with an infected person. Lice that feed on humans do not thrive on animals (so Fido is safe). Head and pubic lice are diagnosed by a health care provider finding a live nymph or louse. Body lice live on clothing and only move to the skin to feed.

Head lice are the most common type of human lice, and they're most often found on young children and the people that live with them. According to the Center for Disease Control in 2013, about 6-12 million people are infected with head lice every year in the United States (now that's scary)! Pubic lice, which are sometimes called crabs because of their shape, are considered a sexually transmitted disease (STD) and infected persons should be checked for other STDs. Body lice are often found among homeless or overcrowded populations and on people who do not change their clothing and bedding often. While head and pubic lice do not generally cause any other diseases, body lice can spread typhus and trench fever.

Symptoms of pediculosis include:

  • Itching
  • A feeling that something is moving in your hair or on your body
  • Difficulty sleeping- because the lice are most active during the night
  • Sores caused by scratching

The Louse Life Cycle

The adult head louse is about the size of a sesame seed and lives for about 30 days. On the head, they are usually found close to a the scalp, behind the ears and around the neckline. Female lice are bigger than the males and can lay 6 eggs a day. That's like giving birth to 180 kids in one month! The eggs are contained inside the nit (egg nest), which cements itself to the hair shaft and can be difficult to remove.

A magnified image of an adult head louse gripping the hair shaft.

Nits are oval-shaped and can appear white or clear, they can easily be mistaken for dandruff in the hair. Nits hatch in 8-9 days and the offspring are called nymphs. Nymphs look like adult lice, just smaller. It takes 9-12 days for them to mature into adults.

A nit (egg nest) attached to the host

Body lice and head lice have a similar life cycle and appearance.

An adult body louse is similar in appearance to the head louse.

Adult pubic lice are smaller and broader than head and body lice. They are also known as a crab lice, due to their shape.

An adult pubic louse is smaller with a broader body than a head or body louse.

To unlock this lesson you must be a Member.
Create your account

Register to view this lesson

Are you a student or a teacher?

Unlock Your Education

See for yourself why 30 million people use

Become a member and start learning now.
Become a Member  Back

Resources created by teachers for teachers

Over 30,000 video lessons & teaching resources‐all in one place.
Video lessons
Quizzes & Worksheets
Classroom Integration
Lesson Plans

I would definitely recommend to my colleagues. It’s like a teacher waved a magic wand and did the work for me. I feel like it’s a lifeline.

Jennifer B.
Jennifer B.
Create an account to start this course today
Used by over 30 million students worldwide
Create an account