When one woman went to the doctor complaining about her eyes itching, he immediately knew what the problem was. It wasn’t allergies or an infection that had been causing her discomfort. Instead, it was simply a matter of hygiene.

The Chinese woman known as Xu, had been suffering from itchy eyes for over two years. She had tried everything to remedy the problem. She had tried allergy medication and eye drops, but nothing seemed to give her relief. Finally, when her eyes became so swollen and irritated that she could barely see she went to the doctor for help.

After examining her eyes, the doctor immediately knew the problem and asked Xu how long it had been since she had washed her pillow and bed sheets. It was 2017 when she was visiting the doctor and she admitted that it had been at least 2012 since she’d last washed her bedding.

The doctor explained to Xu that she had a bad case of eyelash mites and her bedding was to blame. The easiest fix for her problem was to go home and wash her soiled pillows and bedding.

Eyelash mites are microscopic bugs that thrive in dirty conditions, and Xu had created a perfect breeding ground for the bugs by not changing her sheets. The doctor said she had at least 10 mites on every single one of her eyelashes and that the bugs had been crawling around on her face for years unnoticed.

As disturbing as it may sound, eyelash mites are not uncommon. Doctors say that millions of people are infected with the mites and don’t even know it. Until the condition gets so bad that it causes an allergic type reaction like Xu’s most people never have a clue they have an infestation.

The best protection from the mites is to wash bedding in hot water and detergent regularly.