5 important things to know about lice — and why it’s OK to send your kids to school even if they have them

Head lice have been a dreaded parasite for years, with some schools temporarily shutting down over lice outbreaks. But while many schools and day care facilities have a policy that someone with lice must have no lice eggs (called nits) in their hair before returning, the American Academy of Pediatrics says that's overkill.

In newly published guidance, the AAP says it's actually fine to send kids to school with lice. In the guidance, the AAP points out that head lice are "not a health hazard nor sign of poor hygiene." However, the AAP says that sending a child with head lice into quarantine could cause "significant stigma and psychological stress.”

The AAP's guidance echoes recommendations from the Centers for Disease Control and Prevention (CDC), which says that students diagnosed with live head lice "do not need to be sent home early from school." Instead, the CDC says, "they can go home at the end of the day, be treated, and return to class after appropriate treatment has begun." Nits "may persist after treatment," the CDC says, "but successful treatment should kill crawling lice."

Given how much lice are usually feared, it's understandable to have questions. Here are some lice facts every parent needs to know.

Lice spread through close contact

Head lice are about 2 to 3 millimeters long, and they usually infest the head or neck and attach their eggs to the base of the hair shaft, according to the CDC. They feed on the blood of their host and will die within a day or two without a blood meal, says the CDC. Lice move around by crawling, but they can't hop or fly.

The CDC points out that head lice is spread most commonly by close person-to-person contact. "It's spread when a kid has lice in their hair and they get their head close to another kid," Dr. Danelle Fisher, pediatrician and chair of pediatrics at Providence Saint John’s Health Center in Santa Monica, Calif., tells Yahoo Life. "It's not like the lice are going to jump 50 feet across a classroom to land in another kids' hair."

There are certain signs of lice to be on the lookout for

Keep these lice symptoms on the back burner, according to the CDC:

• Tickling feeling of something moving in the hair

• Itching, caused by an allergic reaction to the bites of the head louse

• Irritability and difficulty sleeping (head lice are most active in the dark)

• Sores on the head caused by scratching

You can also spot head lice and their nits. The nits look like tiny grains of rice that are attached to strands of hair near the base of the scalp. They can easily be mistaken for dandruff, scabs or hair spray droplets, the CDC says. Live lice are about the size of a sesame seed, have six legs and are tan to grayish white, the CDC says.

There are treatments for lice

There are a few different options when it comes to treating lice. Topical treatments such as shampoos and lotions that contain pyrethroids are usually considered the first-line treatments for head lice, the AAP says.

"There are some nonmedicinal ways that lice can be treated but do not have FDA or clinical trial approval," Margaret Quinn, a clinical associate professor at the Rutgers School of Nursing, tells Yahoo Life. The AAP also stresses that they're not approved or endorsed by the Food and Drug Administration (FDA) or AAP for this use. Those can include:

• Essential oils like tea tree oil, geranium oil and lavender oil

• Vaseline

• Mayonnaise

• Melted butter or margarine

• Olive oil

"These can coat and suffocate the lice, but they're not considered as effective as pyrethroids," Fisher says.

It's also a good idea to do the following, according to the CDC:

• Machine wash and dry items that the infested person used up to two days before treatment, including hats, scarves, pillow cases, bedding, clothing, and towels.

• Items that can't be laundered can be dry-cleaned or sealed in a plastic bag for two weeks.

• Vacuum furniture and floors that may contain an infested person's hairs (that could have nits attached).

It can take a while to fully get rid of lice

Getting rid of lice can be a tedious process. A pyrethroid treatment needs to be used again in nine or 10 days in order to be effective, the CDC says. You'll also need to use a special comb on the hair and actually try to pick nits out that you spot, Fisher says. "That is key," she says. (Otherwise, the nits can hatch and cause issues all over again.) But, Fisher adds, "the combing out and nit-picking can be very tedious."

Dr. Jennifer Haile, a pediatrician at Connecticut Children's, tells Yahoo Life that it's important to make sure you look at everyone in the home as a possible lice target. "The biggest thing is, if you have close household contacts, that you're making sure you're treating those household contacts and treating the home appropriately," she says. "Anything you can't wash or vacuum needs to be in a sealed plastic bag for two weeks. You don't want to reinfect anyone."

Dr. Fred Archer, a clinical assistant professor of pediatrics in the Jacobs School of Medicine and Biomedical Sciences at the University at Buffalo and with UBMD Pediatrics, tells Yahoo Life that this whole process can take a while. "Barring reinfection, it can take between 14 and 21 days to completely clear an infection," he says. "Most active lice and nits are removed in the first round of topical treatments, though 20% to 30% can survive the initial treatment."

Anyone can get lice

According to CDC data, an estimated 6 million to 12 million head lice infestations happen each year in the U.S. in children 3 to 11 years old. It's most common in preschool children who go to child care, elementary school children, and the household members of infested children, the CDC says.

"It's more common in younger children, because they're more likely to be all over each other," Fisher says. Still, "everyone can get lice," Quinn says, noting that "lice affects all homes, all demographics and all people."

If lice enter your home, you need to be wary. "Living with a child — or adult — with head lice creates a lot of these opportunities for the lice to spread from person to person," Dr. Gary Reschak, pediatrician at Northwestern Medicine McHenry Hospital, tells Yahoo Life

If your child happens to get lice, Fisher says it's important to watch yourself for symptoms too. "If your child has been near you, lay on your pillow or used your hairbrush, it's prudent that you do the same treatment and wash your bedding and clothing in hot water," she says.

Haile adds: "If you don't stop it, it just doesn't leave the house. It can be really frustrating."

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