Over the years, the newer strain of lice has become more resistant to the different toxic chemicals that are used in these OTC treatments. So no matter how strong those treatments are, the lice have the power now to stay stubbornly alive.
In existence for basically as long as humans have been around, lice aren't likely to become extinct any time soon. In particular, head lice are very common, and getting them is not an indication of improper hygiene.
They serve no greater purpose in the ecosystem, as they are literally just a parasite that lives on the human. No animal has them as a staple of their diet, so if they went extinct, all that would happen is that we'd no longer get lice.
Clade B head lice are thought to have originated in North America, and then to have migrated to farther reaches of the world, including Australia and Europe.
Throughout ancient Egypt, people were tormented with lice. Remedies for the common person included eating a special meal mixture with warm water, and then vomiting it up. Others believed a recipe of spices mixed with vinegar rubbed on the scalp over a few days would suffocate them out.
Lice and nits can't survive the high heat. It's true that lice and nits can't survive temperatures above 113°F (45°C). This makes them susceptible to any heat source, such as a hairdryer or the plates of a hair straightener.
There are recent studies that show that treatment of lice with heat can be quite effective in killing head lice. Products such as Lousebuster are very effective but even a home hairdryer can successfully treat lice.
The oldest physical evidence of head lice on a human was a nit found on the hair of a 10,000-year-old body at an archeological site in Brazil. Lice combs have been found in the tombs of Egyptian royalty, and even Cleopatra was said to have solid gold lice combs buried with her.
The most likely explanation is that by the time H. sapiens evolved in Africa about 200,000 years ago we had our own lineage of head lice, and then picked up more from H. erectus on our travels, says Reed. The study is reported in the current issue of PLoS Biology1.
In the middle ages, humans couldn't get away from lice. They were an unavoidable part of their life and lice didn't discriminate; they infected all parts of society from serfs to royals. People in the Middle Ages took lice to their grave as well.
Lice for Building Immunity
Recent studies have shown the benefits of having lice. While it may sound ridiculous and unbelievable, there's scientific evidence that a certain kind of louse can be beneficial in reducing the chances of developing immune deficiencies.
The head lice may have become resistant to the treatment. If the treatment used does not kill the head lice, your health care provider and pharmacist can help you be sure the treatment was used correctly and may recommend a completely different product if they think the head lice are resistant to the first treatment.
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.
Head lice are a common problem, especially for kids. They spread easily from person to person, and sometimes are tough to get rid of. Their bites can make a child's scalp itchy and irritated, and scratching can lead to infection. Head lice are annoying, but they're not dangerous and they don't spread disease.
It is unclear whether or not any of these concoctions actually worked or not, but they certainly sound interesting. In the 1700s, humans' dealings with lice inspired a trend of wearing perukes, also called powdered wigs. For the perukes to fit the right way, the head had to be shaved.
Head-to-head contact with an already infested person is the most common way to get head lice. Head-to-head contact is common during play at school, at home, and elsewhere (sports activities, playground, slumber parties, camp). Although uncommon, head lice can be spread by sharing clothing or belongings.
You can find head lice on the scalp, neck, and ears.
In the United States, infestation with head lice (Pediculus humanus capitis) is most common among preschool- and elementary school-age children and their household members and caretakers.
Blow dry your child's hair. It has to be thoroughly dry down to the scalp to suffocate the lice. Expect this to take 3 times longer than normal drying.
So, the realistic answer is “No, you can't drown lice.” The best treatment for lice is to get them picked out by a professional – Lice Geeks, for example – using the right comb. Even over-the-counter shampoos and products aren't as effective as a well-trained professional wielding the proper comb.
Shaving Will Not Get Rid of Lice.
The reason shaving will not work is because lice live on the base of the hair, and on the scalp. The nits are laid right at the base of the hair oftentimes against the scalp. Shaving will not get close enough to make an impact on the lice and nits.
Typically, 10–15 head lice are found. The number of lice often depends on personal hygiene, for example, how often the person bathes, shampoos, or changes and washes his/her clothing.
Hairspray makes it harder for the louse to grab hold. The smell of hairspray and the use of solvents (sad but true) in them can also deter creepy crawlies from finding their way in. Not to mention that if you're tying longer hair back, you've got a double whammy.
Tea tree oil appears to be able to kill some live lice (at least when used in conjunction with lavender oil), however we know that over-the-counter lice treatments are far more effective at killing live lice and getting rid of the eggs once an infestation has occurred.
Items that cannot be laundered such as headgear, earphones, and bike helmets, can be placed in a plastic bag and put in a freezer. If the freezer is 5°F or lower, all lice and eggs should be dead within 10 hours. Also, keep items and areas off-limits to people for 48 hours to limit exposure to any live lice.