Torres Strait Islanders believe they are being denied a basic first-world human right to clean drinking water after cryptosporidium has been detected in the water supplies of three islands.
There is no set guideline value for the parasite in the Australian Drinking Water Standards, but cryptosporidiosis is an immediately reportable infectious disease.
The water test was organised privately by a Thursday Island resident in May, concerned with the lack of response by governments.
"There's a dirty colour to the water … people are getting sick, stomach bugs and stuff," said Thursday Island resident Rita Kebisu.
Queensland Health said Thursday Island's hospital has seen no unusual levels of water-related illnesses.
Eight cases of cryptosporidiosis have been reported in the Torres and Cape region in 2018, up from two last year, while there were 23 cases in 2016.