Torres Strait Islanders have received ‘boil water’ alerts after cryptosporidium was detected in their water supplies.

The parasite was found at levels of 2.0 (oo)cysts/10L in samples tested by Cairns Regional Council's Water Laboratory.

The is no official guideline for the parasite in the Australian Drinking Water Standards, but it is required that cryptosporidiosis is reported immediately.

The water test was organised by a private citizen who was concerned that governments at all levels were not responding.

A joint Torres Strait Council and Queensland Health statement was issued telling people to boil their water, citing “turbidity and a bacterial risk” in the water supplies of Thursday, Horn and Hammond Islands.

Residents say water quality has deteriorated in the past two years.

“There's a dirty colour to the water … people are getting sick, stomach bugs and stuff,” Thursday Island resident Rita Kebisu told the ABC.

“We seem to be going backwards into third world standards when we still need to boil our water.”

Queensland Health says there have been no unusual levels of water-related illnesses at island hospitals.

“We all put it down to the normal virus going round, a 24-hour virus, you've got a bit of diarrhoea, vomiting,” said another island resident, Chi Chi Fujii.

So far, eight cases of cryptosporidiosis have been reported in the Torres and Cape region this year.

The Queensland Government pledged $12 million in its most recent budget for projects to deliver improved water quality on the islands, but these projects will not be completed for another two years.