At least 100 dead from swine flu worldwide

Hundreds of air travellers will be offered Tamiflu as reports of suspected swine flu cases spread across the country.

As the global death toll rose above 100, New Zealand health officials were investigating suspected cases in Auckland, Hamilton, Palmerston North, Nelson, the West Coast, Canterbury and Otago. Some patients were isolated at home and were being treated with the anti-viral drug as a precaution.

In Wellington, a district court trial was aborted because the judge, who had flown back from the United States at the weekend, was concerned about her flu symptoms.

Pharmacies were inundated with inquiries from worried customers wanting Tamiflu and face masks.

The Health Ministry was still waiting for results last night from screening swabs taken from three Northcote College students who exhibited flu-like symptoms after a school trip to Mexico. They were among a group of 14 who returned home on Air NZ flight NZ5 on Saturday. The test results today revealed they tested negative for Influenza A.

The ministry will begin tracing the 269 passengers on that flight today. It has already traced most of the 364 people on another flight NZ1 after cases of influenza A were confirmed in 10 Rangitoto College pupils who had been on board.

Two of the 10 were taken to hospital. Both have since been discharged after treatment with Tamiflu.

Health Ministry emergency planning national co-ordinator Steve Brazier said last night that the drug would be offered to every passenger on flights NZ1 and NZ5, regardless of symptoms. "We've got the Tamiflu and that's what it's there for. We're ready to ring-fence around the problem and blitz it."

The ministry will not know until later this week whether the infected people have swine flu. Swabs have been sent to the World Health Organisation laboratory in Melbourne for analysis.

Ministry director of public health Mark Jacobs said the facts that initial testing had identified the Rangitoto College strain as influenza A and that the pupils had been in Mexico suggested it was swine flu, rather than a seasonal strain. He said it was unlikely the virus would have spread through the plane. Only those passengers who had sat near the infected pupils were likely to be affected.

Health officials began screening incoming passengers from the Americas yesterday. About 1000 passengers from five flights were observed as they arrived at Auckland and were told to contact a health professional if they had flu-like symptoms.

The ministry says anyone with flu-like symptoms who has returned from trips to North America and Mexico in the past two weeks should see a doctor.

This season's flu vaccine is not thought to give substantial protection against swine flu, but Tamiflu does. It usually takes about six months to develop a vaccine for a particular strain.

WHY ARE HUMANS CATCHING PIG FLU?

Normally, swine flu affects only pigs, or occasionally people who have direct contact with pigs. But the new influenza H1N1 virus is a never-before-seen mix of different animal and human versions of swine flu. Although it's called swine flu, the new strain is not infecting pigs and is being passed human to human.

HOW DANGEROUS IS IT?

More than 100 people have died in Mexico and thousands have become sick. A worrying fact is most of the dead were aged between 25 and 45 rather than being elderly or very young. The first victims of the deadly Spanish flu pandemic of 1918 which caused 50 million deaths worldwide were also healthy young adults.The good news is that Tamiflu appears to be effective against the new strain. So far the suspected cases found in New Zealand do not appear to be serious.

WHY SO MANY DEAD IN MEXICO?

One theory is that something increased the strain's potency, like co-infection with another microbe or unwittingly dangerous treatment.

HOW DOES IT KILL?

Viruses kill their host by over-stimulating immune systems that are robust and healthy. That is why healthy adults with strong immune systems can be hit hardest. Inflammation and leaking fluid in lung cells can effectively drown victims from inside.

HAS IT HAPPENED BEFORE?

An outbreak among soldiers in New Jersey in 1976 caused one death. A 2005 outbreak in China killed 34 people.

CAN I CATCH IT FROM PORK?

No. Cooking pork kills all bacteria and viruses.

- By REBECCA PALMER and MATT CALMAN, The Dominion Post