Lice… The word alone makes most people start to itch… but what do you really know about them? How they survive, how they reproduce, how common they are–especially here, in the Rio Grande Valley?

Lice have a three-stage life cycle: the egg — or nit, nymph and adult.

Experts say nits are laid by adult female lice, close to the base of your hair, typically within 6 millimeters of the scalp.

“Whenever you don’t have control of it, and you don’t get rid of them, it’s a nightmare.”

In about a week, nits hatch, and become nymphs. The nymph stage lasts another week, before the insects mature into adult lice, which are about the size of a sesame seed.

“They lay eggs about 9-10 days later, then after that, every time they lay eggs, it will be around 9 to 10 eggs, and the cycle repeats every two weeks.”

Adult lice cling to the base of the hair, with tiny claw-like feet. They’re usually found around the ears, and along the hairline, near the back of the neck. According to the centers for disease control, adult lice can live for up to 30 days on a person’s head, feeding off their blood.

“If the head lice falls from the hair, it will die within 24 hours, because it needs the hair temperature to continue to be alive.”

Head lice can’t survive in extremely cold or hot temperatures. They’re most healthy at 80 degrees Fahrenheit, and they become more active when humidity is high, making the Rio Grande Valley, a perfect habitat.