They crawl around your face at night, feeding off your oil and skin cells. They have no anus, so eventually explode inside your hair follicles.
Meet the demodex mite, an eight-legged arachnid that mates on your face during the night before turning your facial pores into a nest.
“Everybody's got them. They're a normal thing that lives on the skin,” medical director of Skin & Cancer Foundation Australia Stephen Shumack said.
“It's part of our natural skin flora and fauna.”
Even if the demodex mites are “normal”, their state in life is enough to make you squirm.
Demodex are tiny mites and usually live down the hair follicles on hair-bearing skin, Dr Shumack said.
They grow in size on a meal of facial oil and skin cells during the day, then spend their evenings having sex on the surface of the skin before the female demodex will lay eggs inside the hair follicle.
“It eats what's left on your skin like oil and old skin cells and starts to grow inside. As it does that, it grows in size and when it dies it can cause inflammation on the skin,” said registered skincare nurse Alexandra Matkevich, from Sydney's ENT Wellbeing clinic.
The mites are a natural part of the environment and can transfer between people by a simple touch.
The organisms are often found in eyebrow hair follicles or around the eyes, she said, and can only be seen under a microscope.
An overgrowth of the mites has been linked to conditions such as rosacea, where people over the age of 30 develop sensitive red lumps and bumps over their nose or the middle of the face.
However, Dr Shumack said it was unknown whether demodex cause rosacea or if the inflammation of the skin provides a conducive environment for the mites to increase in numbers.
But before you go scrubbing your face with heavy duty exfoliant, Dr Shumack warns that excessive cleaning can throw one's skin off-balance and introduce less favourable bacteria.
“Everything in moderation - the quick cold showers, don't over scrub or wash, don't use too much antiseptic. Just be fairly gentle with your skin,” he said.
“If you've got normal skin you shouldn't be thinking about demodex because they're normally there."
Ms Matkevich said soap and water was the best method to keep natural organisms in check, such as staphylococcus - also known as golden staph, a common bacterium found on the skin but which can develop into a “nasty infection” if it enters a cut in the skin.
“Usually the bacteria is quite helpful so that's why it's important not to use hospital grade skin cleansers because they kill off good bacteria on your skin.
“If you cut yourself, use water to wash it and if you notice any infection head straight to your doctor for antibiotics,” Ms Matkevich said.