Public Health South has immunised dozens of hotel staff who worked with a Korean waitress found to have hepatitis A.
Potentially thousands of guest could have been exposed to the disease through contact with the waitress at Queenstown's Copthorne Hotel between April 20 and May 3.
So farno further cases had been reported and this was encouraging, Public Health South medical officer of health Dr Marion Poore said.
However, it would not be until the end of June that the disease's incubation period would be over, she told the Southland Times.
The waitress was newly arrived in New Zealand when she started work at the Copthorne.
Dr Poore said she may have had the disease when she arrived here but it could not be detected until she got sick. She was now recovering and planned to return home.
At Public Health's Queenstown clinic on Saturday, 56 of her close contacts, mainly co-workers, were given an injection of immunoglobulin and a vaccination, to help prevent them developing the disease.
About 15 other close contacts were seen in other parts of the country, Dr Poore said.
The cost of providing immunoglobulin and vaccination would be several thousand dollars.
Hotel staff were helping Public Health South track down the 3000 hotel guests who were exposed to contact with the waitress.
The majority of these people were likely to have left the country and would be contacted through their tour groups.
The disease is highly contagious but will run its course like many other viruses. It can be contracted by hand to mouth contact and food and water which has been contaminated with the virus.
Symptoms include nausea and vomiting, jaundice, lack of energy, stomach upset and pains, fever, and general aches and pains.
