Lice are six-legged parasites that are becoming increasingly resistant to shampoos and over the counter treatments. Spread from student to student as they huddle over their phones and iPads, lice are resurgent as a major American health problem.
Chances are that "nitpicker" isn't a career possibility you explored with your high school guidance counselor. Removing lice the old-fashioned way, by combing them out of the hair, has nonetheless become a growth industry in the United States as a problem that used to be short-term and rare has become chronic and common.
As shampoos stop working and schools allow lice-infested students to attend classes rather than requiring them to stay at home, more and more children and teens--the American Pediculosis Association estimates 12 million children every year--are coming down with infestations of the creepy crawly insects. One famous nitpicker, Lauren Salzberg, also known as The Potomac Lice Lady, sees clients in her office in her stately suburban Washington, D.C., from as far away as Atlanta, and professionals like her are popping up all over the United States. When some people come in to see professional nitpickers, they are panicked. Most of them are itchy.
What Are Lice, and What Is Lice Infestation?
Lice are one of the oldest human health problems. Archaeologists have found fossilized louse eggs that are 10,000 years old. Humans have been dealing with lice for so long that references to lice are even part of the language in words and terms such as "lousy," "nitpicking," and "going over things with a fine-toothed comb."
A louse (plural, lice) is a tiny parasite that lives on human skin, especially in hairy areas. Lice do not infest any organisms other than humans, and you can't catch lice from or give lice to your pets, although chimpanzees are susceptible to a closely related species. This wingless insect is no more than about 2 to 3 mm long even as an adult, unable to fly or hop, forced to crawl from one place to another. There are several species of lice, Pediculus capitis (lice on the head, common among children), Pediculus corporis (body lice, especially on arm pits), and Pthirus pubis (pubic lice, often called “crabs”).
Body lice can lay their eggs in the seams of clothing, but head and pubic lice lay their eggs at the bases of hair shafts. A female louse lays about 10 eggs a day, gluing them in place on clothing or on the skin. The baby lice called nits hatch in 8 or 9 days and mature in another 10 to 12 days. Adult lice live about 30 days if they are able to stay on the human body, but they die in just 1 or 2 days if they are deprived of contact with their human hosts.
Lice feed on human blood. Approximately five times a day they attach themselves to the skin with hooklets on their six legs. Their mouth parts retract into their bodies when they are not drinking blood. Lice digest blood slowly enough that lice have been used to identify victims and assailants in crime scene investigations.
Lice infestations usually consist of just 10 adult female lice, although up to 1000 of the insects have been removed from heavily infested people. The presence of these tiny insects is not benign. Their bites trigger itchy, sometimes painful allergic reactions. Head lice do not carry other infectious diseases, but body lice can spread R. prowazeki, which causes typhus; B. quintana, which causes trench fever; and B. recurrentis, which causes relapsing fever.
About 30 percent of people who have pubic lice also have a sexually transmitted disease such as gonorrhea, chlamydia, syphilis, or HIV.
How Common are Head Lice? And Who Gets Them?
Just how common are lice infestations? School surveys have found head lice infestations in:
- Up to 4 percent of children in schools in Mali.
- Up to 8 percent of children in schools in Saudi Arabia.
- Up to 9 percent of children in schools in Belgium.
- Up to 31 percent of students of schools in the UK.
- Up to 59 percent of students in schools in Turkey, and
- Up to 61 percent of students in schools in the United States, where no-nit policies result in 24,000,000 absences from school every year.
Head lice are more likely to affect girls than boys (since girls have longer hair). They are more likely to affect whites and Asians (due to the shape of the hair shaft).