Where do head lice come from?
When your child or someone close to you gets lice, dozens of questions come to mind. What’s the best way to get rid of it? How did they get it? Is it spreading?
Next, most people start questioning what they think they know. Old wives’ tales and outdated information get mixed in with facts, and it’s hard to know what is true and what is myth. Unless you’ve dealt with lice before, there are a lot of unknowns.
Fortunately, the basics of lice removal, care, and prevention are pretty clear. So whether you’re dealing with it right now, or preparing for the future, it’s always a good idea to take a minute to separate lice facts from lice myths. Read on for more head lice facts!
Do lice like clean hair or dirty hair?
Hygiene is not a risk or prevention factor for lice. They don’t care how clean or dirty a person’s hair is, and are just as likely to infest a clean head as an oily one.
Do lice like clean hair? You may have heard that lice prefer dirty hair, or that you can get lice from not washing your hair enough, but it’s an unfortunate myth. Poor personal hygiene may be a risk factor for body lice, but head lice aren’t picky.
Do lice jump?
So, do lice jump? Head lice can crawl but they do not jump. They do not have powerful legs, so they cannot jump. They don’t have wings, so they cannot fly. However, they can crawl short distances and move quickly. Jumping lice is a persistent myth—perhaps because fleas jump, and they seem very similar to many people—but it’s not true.
Can you go to school with lice?
There was a time when children with lice would be sent home early and asked to stay home until the lice were treated and completely removed. This is no longer a concern.
Children or teenagers with lice do not need to be sent home early. They should be instructed to avoid head-to-head contact with other students—such as hugging or putting heads together to look at a book or tablet—but otherwise they can stay in school until the end of the day. The lice should be treated as soon as possible when they do get home, and they can return to school the next day.
The idea that kids should stay away from school if they have lice is an especially unfortunate myth because it singles out kids and can often inspire bullying. Excluding kids from normal activities because of the presence of lice fuels other lice myths about hygiene and disease, and provides a basis for bullying.
Where do lice come from?
A commonly asked question we receive is “where do lice come from?”:
A lice infestation on one individual usually comes from contact with another infested person—usually when heads touch during hugging or huddling around a small object.
The female louse lays eggs, called nits, that attach to hair shafts. Lice nits hatch in about one week, and the lice grow to adults in about one more week.
Are there natural remedies for lice?
There are a few natural, home remedies for lice that many people have heard of, including:
- Wet-combing — Wet-combing involves spraying conditioner on wet hair and using a lice comb (and a magnifying glass) to remove each individual louse. It can be effective, but it is extremely time-consuming.
- Smothering — Smothering lice is really a variation of wet-combing that involves coating the hair in olive or almond oil before combing. This process needs to be repeated daily for a week or more to be effective.
- Treating with essential oils — Essential oils are sometimes used with combing as well. Several oils have been used to kill lice, but additional research is still needed to prove which essential oils are harmless to children. All essential oils should be diluted before being applied to children’s skin.
Most natural remedies for lice involve intense combing, and most are still being proven as safe and/or effective. It might be too drastic to call smothering or essential oils myths, but further testing is needed.
There is one natural remedy that has been scientifically proven to eliminate head lice. NovoKid is an all-natural, pesticide-free lice treatment that only takes four, 10-minute treatments to eradicate lice. It is simple, dry, and does not require combing.
Can Black people get lice?
Do black people get lice? It is much less common, but yes, Black people can get lice, just like any other human with hair. Lice do not discriminate.
The idea that Black people can’t get lice is a very common myth because it happens so rarely. One study found that only 0.3% of Black school children in the U.S. got lice, compared to about 10% of white school children. It’s easy to understand how the myth survives.
Most experts agree that the shape, and resulting density, of afro-textured hair is what makes lice so uncommon in Black communities. It is harder for lice to crawl through the scalp, and it is harder for them to cement nits to hair follicles.
There is some debate about whether the use of oils in Black hair kill lice, but this is probably another lice myth.
Does hair dye kill lice?
Hair dye might kill lice, but it is not an effective treatment for lice.
Hair dye uses strong chemicals, so it makes sense that microscopic insects would not be able to survive being coated in it. The difficulty is that hair dyes are not regulated and tested the way that lice treatments are: every brand uses a different combination of chemicals. So if one brand does successfully kill lice, another may not.
Further, hair dye is applied in a single application and no hair dye uses chemicals that can kill nits. So if a particular hair dye does kill lice, the nits will still hatch up to seven days later and cause a second infection. You would have to dye your hair once per week, for two or three weeks, for hair dye to be an effective lice treatment.
Finally, hair dye does not prevent lice. Once the dye is applied and the hair washed, you’re just as susceptible to head lice as at any other time. Dyed hair is not a preventative measure.
Does chlorine kill lice?
Chlorinated water cannot kill head lice. Lice may be temporarily immobilized when submerged in chlorinated water, but they recover quickly once removed from the water.
The CDC further reports that lice have been observed to cling tightly to hair underwater. This confirms that lice cannot be killed in a swimming pool, but also that lice are not commonly spread in swimming pools either. If you’ve heard that taking your child to the public pool to kill off lice is an effective treatment, you’ve encountered another lice myth.
Can you spread lice by sharing a hat or brush?
Lice can, technically, spread by sharing personal items like hats, brushes, and combs, but it is extremely uncommon. Lice is usually spread by direct head-to-head or hair-to-hair contact.
Lice are not particularly sturdy insects. They need to feed every one or two days, so they don’t survive long off of a host. Nits need the warmth of a host to mature and hatch, and if they are removed from one host, they can’t reattach themselves to another one. Nits that are removed from hair will die without hatching.
Again, not technically a myth, but very unlikely.
Can pets get lice?
Pets cannot get lice from a human, nor can they spread head lice to humans. If someone in your house has head lice, you don’t need to worry about protecting your pet—and your pet was definitely not the source.
There are several species of lice, and each one exclusively feeds off of a different type of host. “Head lice,” for example, is the common term for Pediculus humanus capitis, which only feeds on humans. Felicola subrostratus is a species of lice that only feeds on cats.
Do you have to remove every lice nit?
It is not necessary to remove every lice nit. Most lice treatments require multiple applications over the course of one or two weeks. This accounts for hatching cycles.
Lice nits hatch after about seven days. The first application of a lice treatment will kill most of the hatched lice on the scalp. The next treatment will ensure that existing lice are killed, as well as any new nymphs that have hatched. After a full course of treatment, all the nits will have hatched, and the insects treated.
Close inspection may reveal yellow nits still attached to the hair, but these are not viable. Many get attached more than a quarter of a inch from the scalp, which is too far for them to get the warmth they need to develop and hatch. Additionally, you may see white casings, which are nits that have hatched and those insects have been treated.
Can adults get lice
Yes, adults can get lice. Children seem to lice more often—because of behavior or because of pH levels in their scalps—but anyone with hair is equally vulnerable to lice.
Do lice spread disease?
Head lice do not spread disease. They are annoying, and excessive scratching can make the scalp sensitive—or even open the skin to a secondary infection.
But the idea that lice spread disease is another unfortunate myth. It has likely gained traction along with the myth that lice prefer dirty hair, or that bad hygiene is a cause of lice, but it’s just as false.
Lice Myths Roundup
There are a lot of lice myths that continue to circulate and cause unnecessary worry:
- Myth: Lice prefer dirty hair. The truth is, lice have no preference and hygiene is not a factor in getting lice.
- Myth: Lice can jump. Fleas can jump, but fleas and lice are not the same insect—they’re not even related. Head lice cannot jump or fly.
- Myth: Kids shouldn’t be in school with lice. As long as kids avoid head-to-head or hair-to-hair contact, they don’t need to leave school early with lice, and they don’t need to stay home.
- Myth: Most natural lice removal remedies are just as effective as pharmaceutical treatments. Most natural remedies have not been proven, except for the Novokid system.
- Myth: Black people cannot get lice. Lice don’t care about hygiene, age, or ethnicity. Lice is less common in Black communities because afro-textured hair makes infestations harder, but it is possible.
- Myth: Hair dye is an effective lice treatment. Some hair dyes might kill lice, but no hair dyes kill nits, which makes it an ineffective treatment option.
- Myth: Chlorine can kill head lice. Chlorinated water does not kill head lice.
- Myth: Lice is spread in public pools. While lice can survive underwater, they cling tightly to hair follicles when submerged and are not generally spread in pools.
- Almost myth: You can spread lice by sharing hats and brushes. This does occasionally happen, but it’s extremely rare.
- Myth: You can get lice from (and give lice to) pets. Head lice only live on human scalps. You cannot spread lice to, or get lice from, your furry family members.
- Myth: You have to remove every nit to fully treat lice. Most nits are not viable and what often appear to be nits are empty casings. Neither threatens a future infestation.
- Myth: Adults cannot get lice. Lice are more common on children, but anyone with hair is fair game for lice.
- Myth: Lice spread disease. The CDC does not consider head lice a public health issue, because they have never been known to spread disease.
If your child has lice, don’t panic. It’s annoying, but there’s no greater risk at hand, it’s not a sign of poor hygiene, and your pets are fine.
If your child has lice, or if a friend or classmate has lice and you want to be prepared, the first step is to effectively separate lice fact from lice myth. The second step is to decide on a treatment option. Even if you’re not dealing with head lice right now, it’s never a bad idea to have an over-the-counter or natural lice treatment option on-hand.