These organisms are called demodicids. The tiny parasites live in pores and hair follicles around the eyelashes, feasting on dead skin cells and oils. Demodicids are extremely common in humans. Although the presence of parasites on people might sound alarming, demodicids are harmless and don’t transmit diseases. In some people, usually those with extremely oily skin, or those who use cosmetics heavily, large populations may develop.