If you hear that your kid (or one of their friends) has head lice, your first reaction might be a mixture of disgust, panic, and an urge to disinfect everything in your house. That would be overkill, as the CDC recognizes: They do not recommend that children with lice be sent home from school. Head lice may be icky, but they aren’t an immediate threat to anyone’s health and they don’t spread easily.
Head lice aren’t dangerous
Head lice are little insects that live in hair, feeding off blood in the scalp. Gross, to be sure. They are perfectly adapted to living on our heads: Their little feet hook onto strands of hair. When they lay eggs, they glue them to individual hairs, right next to the scalp.
That’s all they do, though. They don’t transmit disease, or cause any major health problems. Their distant cousins, body lice, do, but those are clothing-dwelling bugs that are only an issue if you go without changing your clothes for weeks. A case of head lice, on the other hand, doesn’t mean you’re living in filth. Head lice can survive shampooing, so they can end up on any head, no matter how clean.
Head lice need to bite your scalp for every meal (again, ew) and after a few weeks of this, you might become sensitized to their saliva, and begin to itch. Kids often aren’t diagnosed with lice until a parent or teacher sees them scratching their head. I asked pediatrician Dr. Cynthia D. Devore, who wrote the American Academy of Pediatrics’ 2015 guidelines on head lice (there has since been a 2022 update) what the worst case scenario is for a kid with a terrible case of head lice. She said it’s possible that with enough scratching, a kid could end up breaking the skin, which could maybe lead to infection. The same would be true of any kind of scratch or cut, though. She asked me to “please stress…that lice are a nuisance, not a life-threatening condition.”
A few years ago, hard-to-kill “super lice” began making the news. A paper in the Journal of Medical Entomology reported that a gene that gives the bugs resistance to some insecticides was more widespread than we previously thought. But this is just putting numbers on a problem that doctors and entomologists already knew about: some bugs are resistant to some insecticides.
Head lice don’t spread that easily
You don’t have to worry about your pets, your stuffed animals, or your furniture. Head lice live on human heads—that’s it. They die after a day or two without a meal (of human blood, sorry), so you have little to fear from a hat that was last worn a week ago, or a stray louse that fell onto your carpet.
In fact, you’re not likely to get lice from a hat or pillowcase at all. Transmission this way is possible, but rare. Instead, lice move from head to head directly. If two kids are engrossed in the same book or iPad game, staring at it with their heads touching, that’s when lice can spread.
In fact, most “back to school” cases of lice probably don’t come from schools at all, since kids aren’t usually rubbing their heads together during class. Devore points out that if you don’t catch a case of head lice until the kid starts scratching their head, you’re probably only spotting cases that are at least a few weeks old. That means if they start itching in September, they’re more likely to have caught the lice at summer camp.
If you want to notice lice when they first move in, you’ll have to check your kid’s head frequently. Lice can be hard to see, so this isn’t an easy job. While Devore recommends it, I don’t see myself taking time out for regular inspections of my kids’ hair.
It’s probably smart to avoid sharing hats and other items that come into contact with hair, but there’s no need to be paranoid about it. If a sports team is sharing helmets, for example, it’s better to wear the helmet than to put yourself at risk of head injuries for fear of lice. Wiping a hat or helmet with a wet paper towel is usually good enough to remove stray lice, Devore says. You could also let the hat sit in a plastic bag for 72 hours. She doesn’t recommend insecticide sprays, because there’s virtually no benefit to outweigh the risks of exposing kids to the chemicals in the spray.
It’s annoying, but not impossible, to get rid of head lice
Every year, six to 12 million children get head lice. Adults can get them, too. You’ve probably heard of a few cases in your school (some schools notify parents) or maybe heard the buzz about “super lice” in your state. If you do end up with head lice—on your kid’s head, or even on yours—don’t give up hope.
First, if it’s a teacher or school nurse that discovers the lice, they should not pull your kid out of school for the day. Schools’ policies vary, but the American Academy of Pediatrics is adamant that children “should not be restricted from school because of lice, because head lice have low contagion within classrooms.” The National Association of School Nurses agrees. Devore says that a child with lice should stay in class, and their parents can treat them for lice that evening. The school nurse should then inspect the child’s head for lice daily for two weeks. Some schools demand that children stay home until the treatment is finished and the eggs are gone. Devore says if your kid stands to miss a lot of school and you want to fight the policy, consider contacting the U.S. Department of Education’s Office of Civil Rights, because this shouldn’t be interfering with their right to an education.
The best treatment for lice is to use an insecticidal shampoo, but there are some caveats here. First, you may want to check that your child actually has lice before dousing their head in pesticides. Dandruff and dirt are often mistaken for louse eggs, and even if you find actual eggs, they may be from an earlier infestation that resolved itself before you ever noticed. Instead, you’re looking for actual living lice. They’re tiny, about the size of a sesame seed, and their eggs will be within half an inch of the scalp. Use a louse comb; a typical infestation only has about 10 live lice, so they’re hard to see. The comb catches nits and lice and removes them from the hair.
Insecticidal shampoos aren’t perfect, but they are the most reliable treatment
There are many different kinds of shampoos that kill lice, but the bugs, including those previously mentioned “super lice,” can be resistant to some of them.
Checking in with your pediatrician is a good idea, Devore says, because they may have a sense of which shampoos tend to work best on your local lice. They can also hook you up with prescription strength shampoos. (Here’s a handy chart of the different treatments that are available.) The prescription strength ones have a higher price tag, up to $250, according to Devore. Drugstore treatments are more often in the $25 price range, but if they don’t work and you end up trying them multiple times, they could end up being more expensive in the long run.
Besides resistance, there could be other reasons a treatment doesn’t work. The CDC outlines the culprits here: you may not have followed the instructions exactly, there may have been conditioner on the hair to start with, or you may have used a two-treatment product but applied the second treatment too early or too late. It’s worth double checking that you’ve followed instructions perfectly to avoid having to do the treatment all over again.
If insecticidal shampoos sound too complicated or dangerous, you may be tempted to just smother your kid’s hair in mayo and call it a day. The idea behind mayonnaise or olive oil treatments is to smother the lice, but there’s not enough evidence to say whether these treatments work. Take a chance on them, if you like, just be aware of the uncertainty.
By the way, if your kid really wants to shave their head, that is an effective treatment. It’s by no means necessary, though. If that’s not their preferred hair style, stick with the shampoos and such.
There’s one more option: a professional head lice removal service. They can use the same treatments you might try at home, but many also use an AirAllé, a device that dehydrates lice with air. It’s sort of like a low temperature, high-speed hair dryer. AirAllé’s maker lists removal services that use their product here. Many others are independent, local businesses that you can find by searching in your area or asking around for recommendations. Technology aside, I imagine the big attraction of hiring a service is that you don’t have to get up close and personal with your kid’s headful of bugs.
In case there are a few lice on shared pillowcases or hats, just wash or dry them. Temperatures above 130°F will kill lice. Letting items sit in a plastic bag for a few days will kill any live lice, and if you’re paranoid that eggs may be able to hatch on that hat or hairbrush (unlikely since they need body heat to survive), you can keep the bag closed for two weeks.
