CHARLOTTE, N.C. — Many women are getting eyelash extensions from technicians that apply lash by lash. But now, some optometrists say they're seeing an increase of tiny mites, similar to lice. 

If you're a fan of eyelash extensions, you might want to think about the last time you cleaned them. 

While you might not want to ruin your new set of lashes by cleaning them, one nurse said you really should -- if you don't, it can get pretty gross. 

Optometrists are seeing more mite infestations, or "Demodex." This is due to eyelash extensions that are glued lash by lash. 

"People are getting these instructions, don't rub on them, don't clean them with harsh remover, but people are completely disregarding cleaning them at all," Piedmont Medical Center Registered Nurse Lindsey Neal said.

Neal said the lack of cleaning can lead to a build-up of bacteria.

"If you're not taking care of them, [you] can get an infestation of eyelash mites," Neal said. 

While we all have mites on our bodies naturally, they flock to dirty eyelashes. If they overpopulate, they can cause a serious infection. Symptoms include itching, redness, and swelling. 

Warning: Eyelash extensions could bring tiny mites

Even more alarming? Neal said they are contagious. She said it's critical not to share eye makeup. In addition, she urges people to regularly clean their eyelids and make sure tools used to apply extensions are clean.

Neal also recommends using tea tree oil to clean your lashes. 

The condition is treatable but, it can take some time. Doctors say even if you don't have extensions, you can still get mites if you don't clean your eyes, or if you don't change out your eye makeup. 

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