A rise in infections from a gut parasite in Queenstown

Another two cases of Cryptosporidium infection have been confirmed in the past 24 hours - to a total of at least 17.

Authorities have issued a precautionary boil water notice, although the source of the outbreak still isn't clear.

Te Whatu Ora Medical Officer of Health, Doctor Susan Jack, says the biggest health risk from the illness is dehydration.

She says pregnant people, young children, those with weak immune systems - and older or younger people with symptoms should keep drinking.