Head Lice, Pubic Lice, Body Lice: What Are the Differences?
There are three different types of lice that can infest humans. Even though they are all called “lice,” they are distinct, depending on which area of the body they inhabit and feed from.
Head lice are grey-white in color and are typically about the size of a sesame seed. A head louse will typically live for about one month, and female lice will produce up to ten nits (eggs) per day, attaching them to the hair shaft on the scalp. The head lice nits are so small that they resemble dandruff and are attached with a glue-like substance that makes them very difficult to remove. The nits will hatch after about a week, making them lice nymphs that will become adults in about ten days.
Head lice are the most common type of lice infestation, with up to 12 million people in the United States infested each year. Children aged three to ten years old are most commonly affected by head lice because preschool, elementary, and day-care centers are most likely to have lice. Lice are most often transmitted via direct head-to-head contact. However, hair length and personal hygiene do not factor into your risk for catching them. Sometimes head lice infestations can be asymptomatic, but usually intense itching will accompany the infestation.
Pubic lice are sometimes referred to as crabs because of their appearance—they resemble tiny sand crabs. The life span of pubic lice is slightly shorter than head lice, at just three weeks. Also, the female pubic louse will produce fewer eggs per day (three) than other types of lice. The eggs will be attached to the base of the pubic hair shaft and will hatch after about one week.
This type of lice is generally transmitted via sexual contact. It has been suspected that they could be transmitted through bed linens and clothing, but this is unlikely since the lice will not survive very long without feeding. Besides just the pubic area, pubic lice can also infest the eyelashes, scalp, and even armpits. Intense itching is usually characteristic of an infestation, as well as bluish-colored sores from the louse bites.
Body lice are slightly bigger than head lice, but otherwise have basically the same appearance. The life cycle of the body louse is also similar. The biggest difference is that body lice primarily live and lay eggs in the seams of clothing or bedding. The lice will only come onto the body to feed. They can also survive for up to 30 days away from its human host, making it much easier to spread an infestation.
Body lice are most common in areas or communities where large populations are dealing with poverty, overcrowding, and poor personal hygiene. If mattresses and bed linens are being reused and shared communally, this increases the risk for body lice infestations. Itching is also a symptom of body lice, generally along the areas where seams of clothing are tight against the body, such as waistband line and bra strap regions. Also, red bite marks may be seen on the body in these areas.