A potential positive Covid-19 case stayed at a Department of Conservation hut in Fiordland National Park overnight on Saturday in a party of five.
Anyone who visited Green Lake Hut between 7pm on Saturday and 8am on Sunday was being urged to self-isolate, and get a test immediately and on day five after they were exposed at this location of interest.
It is a remote access backcountry hut that uses a first in, first-served basis.
"The hut sleeps 12, but because it does not go through a booking system, it is not known how many people accessed the hut during the period of interest," the Department of Conservation said.
"DOC will follow MOH [Ministry of Health] guidance on whether the hut needs to be deep cleaned or closed. At this stage, it remains open."
There was no DOC staff member positioned at the hut, and it was unknown whether the affected person was vaccinated or where they came from.
They were considered low risk, DOC said.
"Anyone who was at Green Lake Hut, or a contact of someone who was there on Saturday night, needs to follow health guidelines.
"DOC is still working towards the 15 December compulsory double-vaccination requirement for people to use DOC accommodation."