10.13pm: Confirmation that 11 Rangitoto College students have swine flu is no reason for the public to panic, health officials say.
Health Minister Tony Ryall tonight announced the World Health Organisation had returned positive swine flu results from three of the 11 Rangitoto College students who had tested positive for influenza A.
That was enough to assume all 11 were positive.
However, Director of Public Health Mark Jacobs said the general public was at no greater risk of contracting swine flu than any other type of flu.
"There is no indication it is any more or less contagious than any other form of influenza," he said.
It was most contagious a day before symptoms appeared and up to seven days after. The greatest risk was in the early days.
No age group was any more or less at risk, Dr Jacobs said.
"So far there doesn't seem to be any particular age group that is showing up although, again, as numbers increase around the world we'll get more and more good information on that.
"The reports from Mexico are that it is affecting all age groups."
Dr Jacobs urged people to keep the illness in perspective and said anyone not directly exposed to it was unlikely to contract it.
9.12pm: Tests have "unfortunately" confirmed at least three New Zealanders have tested positive to swine flu, Health Minister Tony Ryall announced tonight.
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 have swine flu.
Tests on a fourth sample were continuing.
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 on Saturday from a trip to Mexico.
6.30pm: The result of tests on 10 Rangitoto College students who tested positive for influenza A are expected from the WHO laboratory in Melbourne tonight and an 11th member of the group has also tested positive for influenza A.
Mr Ryall made a ministerial statement when Parliament sat at 2pm, and told MPs all 10 of the students who tested positive for influenza A after visiting Mexico were on the road to recovery.
But this evening Auckland Regional Public Health Service (ARPHS) clinical director Julia Peters said that one more member of the quarantined Rangitoto College group had been confirmed with influenza A.
2.01pm: Seasonal flu jabs available each year will not work against the new swine flu virus emerging from Mexico, the National Influenza Strategy Group (NISG) says.
There is currently no vaccine available against the strain of swine flu. The group advised that Tamiflu was an anti-viral treatment for influenza - not a vaccine.
"Immunisation can help protect an individual against seasonal influenza strains that are already circulating in the world, but if a new strain of influenza virus emerges, the seasonal vaccine is unlikely to protect against it," said NISG spokeswoman Nikki Turner.
However, seasonal influenza immunisation was still worthwhile, she said.
Influenza immunisation is free for New Zealanders at high risk of complications - people aged 65 and over and people of any age including children, with long-term health conditions.
It is available free from a doctor or nurse to these groups until June 30.
1.08pm: A portrait is emerging of a slow and confused response by Mexico to the gathering swine flu epidemic. And that could mean the world is flying blind into a global health storm.
Two weeks after the first known swine flu death, Mexico still hasn't given medicine to the families of the dead. It hasn't determined where the outbreak began or how it spread. And while the government urges anyone who feels sick to go to hospitals, feverish people complain ambulance workers are scared to pick them up.
Meanwhile, the number of confirmed swine flu cases in the US has risen to 48 after further testing was carried out at a New York City school.
12.51pm: Health authorities say a South Korean citizen is being tested for possible swine flu.
The government's disease control centre said in a statement today that the person is one of three people reported to have swine flu symptoms after trips to Mexico.
The office said the two others have tested negative. It did not give any more details.
News cable channel YTN said it is expected to take about three days to determine whether the person has swine flu.
12.41pm: Scientists in Hong Kong are trying to develop a test that will cut the time it takes to diagnose the new swine flu strain from a few days to a few hours.
Researchers in Hong Kong played a big role in discovering and determining how to treat SARS - a separate deadly virus that spread rapidly in 2003, killing more than 900 people. The island was the second hardest hit after mainland China.
12.07pm: Health Minister Tony Ryall said today that passengers on flight NZ5 (the flight which carried Northcote College students earlier suspected of being at risk) were now in the same category as anyone who had returned from Mexico or the United States in the last fortnight.
They should be vigilant about contacting their GP if flu-like symptoms occurred and would be offered Tamiflu.
Other New Zealanders needed to respond to flu-like symptoms as they always had.
"It's a time for caution and concern, but not alarm," Mr Ryall said.
Public Health director Mark Jacobs said it was likely there was an increased rush of people getting checked for flu symptoms.
He said it was the time of the year when common cold and flu viruses struck and urged the public not to panic if there was no reason to suspect anything worse.
11.36am: Stephen McKernan, New Zealand's Director General of Health says the samples of influenza A taken from the group from Rangitoto College were sent to Melbourne for testing yesterday.
"These samples take a level of preparation and packaging. That was undertaken and they left for Melbourne yesterday afternoon," he said.
10.59am: New Zealand health officials are now investigating 56 more possible cases of swine flu. Ten people from Rangitoto College have already tested positive for influenza A and a further 56 people who have recently returned from America or Mexico and have flu-like symptoms are being tested.
All but 18 of the 356 passengers on NZ1 - the flight the Rangitoto College students were on - have been contacted.
The Ministry of Health is no longer trying to contact passengers who were aboard flight NZ5 as the Northcote College pupils on that flight who were earlier believed to be at risk of influenza A have tested negative.
10.35am: Ten Queenslanders are being tested for deadly swine flu and one passenger has been detained after returning to Australia from Los Angeles displaying symptoms.
Two other people in Queensland were cleared of the virus yesterday after exhibiting symptoms and another two were cleared during the weekend.
Queensland chief health officer Dr Jeannette Young told ABC Radio that the person detained on today's flight would be tested.
"(We'll) then work through whether it's likely they meet the case definition, take swabs, if we do think they've potentially got this new swine flu, then we'll give them a face mask and ask them to go home and minimise contact with other people," she said.
Premier Anna Bligh is holding a press conference to discuss the suspected cases.
10.22am: Health Minister Tony Ryall says it will take between six and eight months to make a vaccine for the new swine flu virus.
Mr Ryall made the announcement at a press conference in Wellington this morning.
10.18am: Canada is tightening the screening process for incoming Mexican agriculture workers in an effort to limit the spread of swine flu.
Immigration Minister Jason Kenney says all Mexican seasonal workers will need to have a fever-check by two doctors, fill out a questionnaire and undergo a physical before entering Canada.
The steps are being taken with thousands of Mexican migrant workers set to arrive on Canadian farms, which rely on foreign help to meet labour shortages during the growing season.
Kenney said the measure was devised in consultation with the Mexican government.
The medical exams must occur before they leave Mexico, Kenney told Parliament.
Canada has four confirmed swine flu cases in Nova Scotia and two confirmed cases in British Columbia. All have links to Mexico.
9.56am: Mexico City's football clubs are expected to keep playing behind closed doors, a measure designed to help stem the outbreak of the swine flu epidemic in the Mexican capital.
Three games were played in fanless stadiums over the weekend, with other sports taking similar preventive measures. A top baseball team is moving its games this week to northern Mexico, and a weekend diving tournament - headed by leading Chinese divers - was held without any fans at all.
With the death toll rising from the epidemic, playing games in empty stadiums is part of a wider effort to contain the outbreak.
"We are going to wait to see how the outbreak develops," said a spokeswoman at the Mexican Football Federation, who said she was not authorised to give her name.
"There is no general policy yet, it all depends on the decision of the individual clubs."
9.31am: Tourism New Zealand consultants overseas are telling potential travellers to New Zealand about the situation regarding influenza, amid the global outbreak of suspected swine flu cases.
Tourism New Zealand Chief Executive George Hickton says tourism officers are working in major overseas tourist markets such as America, Britain, Australia and Japan.
"We make sure that they're in touch with the local travel trade so that if there are inquiries coming in from potential travellers about whether or not it is safe to come to New Zealand, we can answer that accurately.
"The key thing for us at the moment is to ensure that if travellers have questions about New Zealand they get the right information because it is very easy for people to jump to assumptions."
Mr Hickton says one thing in New Zealand's favour is that it does not get a lot of visitors from Mexico.
He says it is too early to speculate on the damage the flu situation is having on New Zealand's international reputation.
Tourism New Zealand is also monitoring international media organisations to make sure they are reporting accurate information on New Zealand.
8.48am: Mexico says the World Health Organisation has raised its pandemic alert for swine flu by one level, two steps short of declaring a full-blown pandemic
Mexico health department spokesman Carlos Olmos confirmed the move.
The WHO says the phase 4 alert means sustained human to human transmission causing outbreaks in at least one country. It signals a significant increase in the risk of a global epidemic, but doesn't mean a pandemic is inevitable.
Many experts think it may be impossible to contain a flu virus already spreading in several countries.
The WHO has confirmed human cases of swine flu in Mexico, the United States, Canada and Spain. Only Mexico has reported deaths from the new strain.
8.30am: The test results on three Auckland students have come back negative for influenza type A, a strain of swine flu.
The students from Northcote College on the North Shore were tested after returning on Saturday from a school trip to Mexico, where more than 100 people have died from suspected swine flu.
They were treated with the anti-viral medicine tamiflu and asked to stay at home.
Test results from students from Rangitoto College are still being analysed in Melbourne after a group also arrived back from a class trip to Mexico over the weekend. The results are expected by the end of the week.
Auckland public health staff are continuing to meet and screen passengers arriving in Auckland travelling from Mexico and the Americas.
Public health staff are also continuing to contact individuals on Air New Zealand flights NZ1 and NZ5 that arrived in New Zealand from Los Angeles on Saturday.
5.50am: Health authorities are trying to track down all cases of illness that may relate to possible swine flu.
In the Auckland region, ten cases of influenza A, a subset of swine flu have been confirmed after groups from Rangitoto College and Northcote College returned from school trips to Mexico. Further test results from three Northcote College students are expected to be made public this morning. It is not yet known if any of the cases are the H1N1 swine flu.
There are also two suspected cases in the Nelson/Marlborough region and two in Waikato. In Canterbury, seven people with flu symptoms have been tested. Officials in Otago and Southland are keeping an eye on nine people who have recently returned from Mexico.
The virus is suspected to have caused more than 100 deaths. There are also suspected cases in Brazil, America, Canada, Australia, Israel and France. Two people are in isolation in a hospital near Glasgow in Scotland as Britain's first cases are confirmed.
Auckland Regional Public Health Service clinical director Julia Peters says authorities are dealing with an evolving situation which involves tracing people who have come into contact with suspected cases and investigating any new cases. Dr Peters says health authorities will also continue their presence at the border and work to support primary care practitioners.
GPs are being inundated with queries about swine flu.
Alistair Sullivan, White Cross Accident and Emergency Centres CEO, says there is not a lot of clear information in the public domain but anyone with concerns, especially people who have recently been in Mexico and the United States, should see their doctor.
A number of his staff are taking the anti-viral drug Tamiflu after dealing with possible flu carriers.
Key developments so far:
* The new virus is called a swine flu, though it contains genetic segments from humans and birds viruses as well as from pigs from North America, Europe and Asia.
Health officials had seen combinations of bird, pig and human virus before - but never such an intercontinental mix, including more than one pig virus.
People appear to have no immunity to the new virus and it seems to spread easily from person to person.
Deaths: 149, all in Mexico, 20 confirmed as swine flu and the rest suspected.
Sick people: 1,995 people have been hospitalised with pneumonia in Mexico but the government does not yet know how many were swine flu, 40 confirmed in the US, 28 at one New York City school. Elsewhere: 6 confirmed in Canada, 10 suspected in New Zealand, 1 confirmed and 17 suspected in Spain, 1 suspected in France, 1 suspected in Israel.
Locations in Mexico: 17 states, including Mexico City, Mexico State, Veracruz, Oaxaca, Baja California and San Luis Potosi. Some, including Oaxaca, Mexico City and Baja California, have tourist areas, but authorities have not said where in these states the outbreaks occurred.
Locations in the US: 8 in New York, 7 in California, 2 in Kansas, 2 in Texas and 1 in Ohio.
Safety measures in Mexico: In Mexico City, surgical masks are being given away on the subway system, public events have been cancelled, schools and public venues have been closed and church services postponed. President Felipe Calderon has assumed new powers to isolate infected people.
Safety measures in the US: Roughly 12 million doses of Tamiflu are being moved from the federal stockpile to be delivered to states. Travellers at the border are being asked about travel to flu-stricken areas. St Francis Preparatory School in New York, where eight cases are confirmed, was closed yesterday and today. St Mel's Catholic School in Fair Oaks, California, is closed until at least Thursday as officials investigate possible infection of seventh grader.
Safety measures worldwide: Airports screening travellers from Mexico for flu symptoms. China, Russia and Taiwan plan to put anyone with symptoms under quarantine. Hong Kong and South Korea warn against travel to Mexican City and three provinces. Italy, Poland and Venezuela advised citizens to postpone travel to affected areas of Mexico and the United States.
- NEWSTALK ZB, AP, AAP, NZPA, NZ HERALD STAFF
10.13pm: Confirmation that 11 Rangitoto College students have swine flu is no reason for the public to panic, health officials say.