A Victorian couple have found they were being eaten alive by small worms with teeth after falling sick several weeks ago.

The couple became chronically ill when they caught and ate a fish, also ingesting gnathostomiasis larvae, while on holiday in Western Australia.

This is the first case where humans have been infected with the parasite in Australia, according to The Australian Medical Journal.

The worms are 1-3mm long, have sharp teeth and can work their way around the body until it dies or is killed by the human immune system.

It can be difficult to diagnose as the worms move under the skin and cause itchy lumps that can make you feel sick.

The 52-year-old man told doctors he could feel movement under his skin.

A course of antibiotics killed the parasite and the couple have recovered.

Worms can live in the human body for up to 15 years, and can travel to the brain, vital organs and spinal chord.