Swine flu has been confirmed to be in New Zeaaland.
At a news conference held tonight, Health Minister Tony Ryall announced that test results confirmed at least three New Zealanders have tested positive to swine flu.
Melbourne tests on 10 Rangitoto College students who tested positive for influenza A came back from the World Health Organisation (WHO) laboratory tonight, confirming three positives to swine flu.
"Unfortunately tonight we can confirm New Zealanders have tested positive to swine flu," Mr Ryall said.
Tests on a fourth sample were continuing, Director of Public Health Mark Jacobs told reporters.
He said three samples all tested positive for the same strain of swine flu. A further sample was being retested.
The swine flu virus has killed close to 150 people in Mexico and infected dozens in the United States, Canada and Europe.
The Rangitoto students returned to Auckland on Saturday from a trip to Mexico. An 11th member of the group has also tested positive for influenza A.
The test results were announced in Wellington tonight, at a press conference attended by Mr Ryall, Director-General of Health Stephen McKernan, Mr Jacobs, and National Co-ordinator Emergency Planning Steve Brazier.
Mr Ryall made a ministerial statement when Parliament sat at 2pm, and told MPs all 10 of the students were recovering.
Mr Ryall told Parliament another 56 people nationwide were being monitored and were being tested to find out whether they had influenza A.
He told Parliament the measures that were being taken were fully justified.
"Officials are ready for any escalation in the domestic or international swine flu situation," he said. "This is a threat that New Zealand has planned for. Many of the best people in the health service are working night and day to protect the health of New Zealanders."
On Saturday morning, flight NZ1 arrived in Auckland from Los Angeles at 5am. On board were the Rangitoto College group which had visited Mexico.
Mr Ryall said the initial response had been rapid, thorough and appropriate for the level of risk at the time.
Their teacher insisted those with flu symptoms contact their doctor and at 12.30pm one of the doctors contacted Auckland Regional Public Health Service.
The Auckland public health response centre was activated by 3pm and by 6pm a team of nurses was assessing the Rangitoto group. All were treated with Tamiflu and isolated with their families by 10pm.
On Sunday night testing revealed the Rangitoto 10 had influenza A. Ministry officials decided they should be treated as probably cases of swine flu.
Mr Ryall said nearly all the passengers on NZ1 had been traced, assessed and offered Tamiflu as a precaution.
The WHO today raised its pandemic alert level to phase 4, indicating a significant increased risk of a pandemic, a global outbreak of a serious disease.
Meanwhile efforts are continuing to trace 18 passengers from the flight whose contact details were unclear.
Watch the full news conference announcing the positive results