As far as we know, there have not been any clinical studies proving any human population to be immune to head lice. However, head lice can have difficultly attaching their eggs to hair that is thick or coarse; therefore, those individuals may be less likely to experience head lice infestation.
Although head lice can feed on different blood types, they cannot thrive on different Rh blood factors. Therefore, lice will only prefer to move to somebody else of the same rhesus factor irrespective of the blood type.
In the United States, infestation with head lice is much less common among African-Americans than among persons of other races. The head louse found most frequently in the United States may have claws that are better adapted for grasping the shape and width of some types of hair but not others.
Adults are not immune to head lice. In fact, if you have any close contact with children or even parents of children you can be at risk of catching them if they have them. Lice transfer primarily through head to head contact, so you would have to get close to the other person.
In order to have nits, you had to have had an adult female lay them. But it is possible to have Nits and no lice in the very early stages of an infestation.
People who had medium long hair had the highest incidence of lice compared to those who had short and long hair. People with short hair were least likely to have lice, and people with thick hair more often had lice than those with thin hair.
Anyone can get head lice, but some people are at greater risk than others. Those people include: Children between the ages of 3 and 11 years. Girls are more likely to get head lice than boys, possibly because of their play styles and sharing of personal items.
Head lice can affect anyone but occur most often among children between the ages of 3 to 11 years old, along with their families. Children are more at risk, as they make head-to-head contact with other children when playing together and may share items that have contact with their hair.
Getting Lice While Bald
They find it difficult to feed and quickly die off. Lice may attempt to attach, but the environment is unsuitable for their survival. While bald people may become temporarily affected by head lice they often leave for a better suited host or die off. Thin or sporadic hair can still attract lice.
Preschool and elementary-age children, 3-10, and their families are infested most often. Girls get head lice more often than boys, women more than men. In the United States, African-Americans rarely get head lice.
Hair gels, hairspray, oils or other non-medicated hair products including dandruff shampoo will not kill lice or prevent eggs from hatching or sticking to the hair.
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.
Head lice infestations can be asymptomatic, particularly with a first infestation or when an infestation is light. Itching (“pruritus”) is the most common symptom of head lice infestation and is caused by an allergic reaction to louse bites.
Look for lice crawling on the scalp where the hair is parted or on the hair shaft. The lice will be dark in color and the size of a poppyseed. Look for nits near hair follicle about ¼ inch from scalp. Nits (eggs) will be white or yellowish-brown.
Infestation timeline
So if you look on the scalp and see no visible adult lice and several small nits, it's likely that you've caught lice in the earlier stages and had them for less than 2 weeks. Nits and nymphs: 1.5 to 2 weeks. If you see nits and small, moving lice, you've likely had lice for 1.5 to 2 weeks.
Small studies have also shown that tea tree oil in combination with lavender oil can kill lice eggs and reduce the number of live lice. Tea tree oil seems to be relatively safe for use on the skin, although it can cause irritation or swelling for some. Remember, though, that it is poisonous if swallowed.
Anyone can get lice, regardless of age, social status, race or gender. Luckily, lice don't spread disease contrary to popular misconception, but they do itch! Lice are parasites that live off human blood. They leave their saliva where they bite, which makes the bite itch.
How many head lice are usually found on an infested person? 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.
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.
They hang around children often
Naturally, parents, teachers and other adults who spend time within close vicinity of children are more susceptible to lice infestations. To sum it up, the reason why some people do not get lice is due to pure luck.
Children can have a few nits without actually having a case of head lice. Usually children have no more than 10 to 20 live lice. Good lighting is important when you are checking. Head lice move fast and are hard to see.
Untreated head lice may degrade the scalp and affects it health and that of the hair. If the follicles become blocked, then hair loss may occur. It is hard to have well-conditioned hair if it is covered in head lice eggs, lice and bacteria.
If you do not comb out all the remaining nits, they will hatch and restart the cycle in 7-10 days from that point. That's why we recommend 3 treatments over a 12-day period of time. This stops the life cycle of lice. These are nits at different stages and a louse.