A Victorian couple discovered they were being eaten alive by potentially deadly worms with teeth, after weeks of chronic sickness.
The couple became infected after eating uncooked 'black bream' and ingesting gnathostomiasis larvae while camping in a remote part of Western Australia.
It is the first time humans have been infected by the rare parasite in Australia, The Australian Medical Journal reports.
The parasite is common in 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.
"The parasite goes through the wall of your stomach and goes through your body." Alfred Hospital's Dr Andrew Fuller told 7News.
"It can eat through tissue."
The couple suffered vomiting, swellings on the skin, abdominal cramps, fevers, muscle pains and lethargy.
The 52-year-old man told doctors he could even feel movement under his skin.
The symptoms began about 10 days after the couple ate the fish, believed to be black bream.
Dr Fuller warned it could be a lethal infection, but added: "I wouldn't let this put you off going adventuring, but I think it's very important to cook things properly."
A course of antibiotics killed the parasite and the couple are now said to be well.
The worms can live in the human body for up to 15 years, and can travel to the brain, vital organs and spinal cord. Dr Fuller says the parasite has been known to claim lives.