At some point, most of us have received a note from our kid's school about exposure to head lice. That’s no surprise, since the Centers for Disease Control and Prevention (CDC) estimates that anywhere between 6 million and 12 million kids are infected each year in the U.S. But when you get that note, what exactly are you looking for? Here’s all you need to know about what head lice and nits look like.
Head lice have three forms: egg (nit), nymph, and adult.
What do nits look like? Oval-shaped nits are about the size of a knot in thread. They're difficult to see, but you can feel them if you run a fingernail down the hair shaft from the scalp. Nits are usually light gray, tan, yellowish, or white in color. "They can look just like a grain of sand, and they're not easily removed from the hair," says Paradi Mirmirani, M.D., a board-certified dermatologist with the American Academy of Dermatology. After the nits hatch, dull yellow shells remain on the hair shaft.
What do lice look like? An immature louse (or nymph) looks like an adult, but it’s about the size of a pinhead. After a week after hatching, the louse grows to the size of a sesame seed, with six clawed leg and a tan to grayish-white color. Note that the CDC says lice may look darker on people with dark hair.
Head lice and their nits are found almost exclusively on the scalp, particularly behind the ears, on top of the head, and near the neckline. They sometimes appear on eyelashes and brows, but this is rare.
Lice grasp the hair shaft with hooklike claws. Since they don’t like light and they're extremely fast, you may only see or feel the nits when closely examining your child's hair. Grab a flashlight, and look or feel for the tiny bumps, which will be cemented firmly to the hair shaft about a quarter-inch from the scalp. Lice can be tough to remove even after hatching, when only the empty casings remain.
If you find nits or head lice when you're examining your kid's hair, stay calm. It's an annoying problem, but a solvable one. "Remember: Lice don't carry disease," says Dr. Mirmirani. "They're icky, yes. But they're no harm to your child's health." Find out about how to treat lice with this helpful guide.