Wellington - Swine flu has spread so quickly in New Zealand that it has replaced seasonal influenza that hits every winter as the dominant strain, according to an expert quoted on Saturday. "The speed at which it has replaced seasonal influenza as the predominant strain just within the last week is incredible," Sue Huang, head of the national influenza centre told Wellington's Dominion Post.
"It's quite alarming," she said, dubbing the new influenza A(H1N1) virus the most contagious bug she had seen.
The so-called swine flu, which has killed at least six people in New Zealand so far, accounted for about 75 per cent of all confirmed influenza cases in the country during the last week, Huang said.
The government this week offered free vaccinations for seasonal winter flu to the entire population in a bid to relieve pressure on doctors swamped by three times as many patients with influenza symptoms as last winter. It was previously free only to pensioners and people with respiratory conditions.
The vaccinations do not counter swine flu, which Huang said had fortunately not mutated and was not yet resistant to the antiviral drug Tamiflu.
She said all cases in which people have died or become seriously ill seemed to be related to individuals with a pre-existing condition rather to than the virus alone.
The New Zealand health ministry reported Friday that 1,555 cases of H1N1 flu had been confirmed, though the actual number is much greater because not all patients are being tested for the new strain.