Pediculus humanus capitis and Pediculus humanus corporis (Head lice and body lice) By: Michelle Raths

Geographic Location: Pediculus humanus capitis Worldwide Anywhere that there are people. On the scalp so that they can maintain their body temperature. Pediculus humanus corporis Worldwide Anywhere that they are people In clothing (skin to feed)

Common Places/Ways to get Head Lice Caucasian Females Elementary schools – 3 to 11 years old Daycares Slumber parties Sharing clothing Sharing combs, brushes, and towels Lying on the same bed, couch, carpet or pillow that an infected person has also lied on. Sharing stuffed animals

Pediculus humanus capitis 2.1-3.3 mm long

Common Ways/Places to Get Body Lice Being in contact with someone who has it Living under crowded conditions Having poor hygiene Homeless Refugees Natural disaster survivors Infrequent bathing Infrequent changing of clothes

Pediculus humanus corporis 2.3- 3.6 mm long

Head Lice-Life Cycle The life cycle of the head louse has three stages: egg, nymph, and adult. Eggs: Nits are head lice eggs.  They are hard to see and are often confused for dandruff or hair spray droplets.  Nits are laid by the adult female and are cemented at the base of the hair shaft nearest the scalp .  They are 0.8 mm by 0.3 mm, oval and usually yellow to white.  Nits take about 1 week to hatch (range 6 to 9 days).  Viable eggs are usually located within 6 mm of the scalp. Nymphs: The egg hatches to release a nymph .  The nit shell then becomes a more visible dull yellow and remains attached to the hair shaft.  The nymph looks like an adult head louse, but is about the size of a pinhead.  Nymphs mature after three molts (, ) and become adults about 7 days after hatching. Adults: The adult louse is about the size of a sesame seed, has 6 legs (each with claws), and is tan to grayish-white .  In persons with dark hair, the adult louse will appear darker.  Females are usually larger than males and can lay up to 8 nits per day.  Adult lice can live up to 30 days on a person’s head.  To live, adult lice need to feed on blood several times daily.  Without blood meals, the louse will die within 1 to 2 days off the host.

Body Lice- Life Cycle The life cycle of the body louse has three stages: egg, nymph, and adult. Eggs: Nits are body lice eggs. They are hard to see and are often confused for dandruff. Nits are laid by the adult female and are cemented at the base of the hair shaft nearest the skin . They are 0.8 mm by 0.3 mm, oval and usually yellow to white. Nits take about 1 week to hatch (range 6 to 9 days). Viable eggs are usually located within 6 mm of the skin. Nymphs: The egg hatches to release a nymph . The nit shell then becomes a more visible dull yellow and remains attached to the hair shaft. The nymph looks like an adult body louse, but is about the size of a pinhead. Nymphs mature after three molts (, ) and become adults about 7 days after hatching. Adults: The adult louse is about the size of a sesame seed, has 6 legs (each with claws), and is tan to grayish-white . In persons with dark hair, the adult louse will appear darker. Females are usually larger than males and can lay up to 8 nits per day. Adult lice can live up to 30 days on a person’s body. To live, adult lice need to feed on blood several times daily. Without blood meals, the louse will die within 1 to 2 days off the host.

Signs/Symptoms Head Lice Body Lice Asymptomatic Intense itching Tickling feeling Irritability Allergic reaction to the louse saliva Secondary bacteria infection Body Lice Intense itching Allergic reaction to the louse saliva Secondary bacteria infection Heavily bitten areas of skin become discolored (around the midsection “vagabond’s disease”

Diagnosis Head Lice Body Lice Finding a live nymph or an adult louse in the scalp or hair of someone. Finding nits no more than 6 mm from the scalp indicates a current infestation and more than 6 mm indicates a previous infestation. Body Lice Finding eggs in clothing Finding adults crawling in clothing (generally the seams) Finding adults crawling/feeding on the human body

Pathogenesis Head lice does not cause any diseases, but may cause secondary bacterial infections. Body lice does cause disease and secondary bacterial infections. Epidemic typhus (no longer widespread) War Civil unrest Natural or man-made disasters Prisons Trench fever Louse-borne relapsing fever http://natgeotv.com/asia/bite-me/videos/body-lice

Treatment Head Lice Body Lice Treat everyone in the house! Then, retreat them! Treat after eggs have hatched, but before new ones are produced. Wash clothing, etc (in hot water/hot dryer). Lice are killed after 5 minutes in 128.3*F Seal items in a garbage bag (stuffed-animals, hats, scarves, etc) for 2 weeks. Vacuum furniture and floors. Over-the-counter or prescription medication Pyrethrins, Permethrin lotion 1%, Malathion lotion 0.5%, Benzyl alcohol lotion (5%), Lindane shampoo 1%, Body Lice Improve personal hygiene Bathe weekly! Wash clothes, towels, bedding in hot water! And machine dry on the hot cycle! Pediculicide – kills lice, not generally used. Brand name products: A-200*, Pronto*, R&C*, Rid*, Triple X*. Brand name product: Nix*. Brand name product: Ovide* Brand name product: Ulesfia lotion*

Prevention Head Lice Body Lice Avoid head-to-head contact Don’t share any head garments or clothes Don’t share combs, brushes, or towels (Disinfect them!!!) Wash and dry clothes bedding, and other things worn or used by those who are infested Vacuum floor and furniture Avoid activities that are prone to spreading lice! Body Lice Bathe regularly Change clothing regularly Machine wash and dry infested and un-infested clothing regularly Seal clothes in plastic bags. Don’t share beds, clothes, towels, or bedding Dusting with chemical insecticides may be necessary to prevent the spread of disease.

Pthirus pubis(crabs)- Pubic lice -1.1 to 1.8 mm in length -Typically found in the pubic area, but may be found on other coarse- haired areas (armpits, eyelashes, eyebrows, beard, mustache chest) -Spread through sexual contact (can indicate sexual abuse to children) -Don’t have sexual contact with an infected individual. -Don’t share clothing, bedding, or towels. -Beware of the toilet seat!!!!!!! Pthirus pubis(crabs)- Pubic lice

REFERENCES: http://www.cdc.gov/parasites/lice/pubic/prevent.html http://www.cdc.gov/parasites/lice/head/prevent.html http://www.licesos.com/lice.html http://www.cdc.gov/parasites/lice/body/index.html http://natgeotv.com/asia/bite-me/videos/body-lice

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