According to a new report in The Australian Medical Journal a couple were being eaten alive by tiny worms with teeth
The Victorian pair discovered this after weeks of chronic sickness.
They first became ill after cooking fish they had caught while on a camping holiday in Western Australia, and ingesting the gnathostomiasis larvae.
It is the first time humans have been infected by the parasite in Australia.
Patients with the same condition contract the illness overseas, including south east Asia and Japan.
The worms are 1-3mm long, have got sharp teeth and can work their way around the body until it dies or is killed by the human immune system.
"They move under the skin and cause itchy lumps that can make you feel sick - and it can be very hard to diagnose," Alfred Hospital's Dr Andrew Fuller was quoted as saying in the Herald Sun.
"They eat your tissues."
The 52-year-old man told doctors he could even feel movement under his skin.
A course of antibiotics killed the parasite and the couple have recovered.
The worms can live in the human body for up to 15 years, and can travel to the brain, vital organs and spinal cord.