SWINE flu infections have spiked in Australia this week, with younger, healthy people being struck down amid warnings the situation will probably get worse over the next two months.
Experts have warned a mass vaccination is needed. The Federal Government has ordered 21 million shots of a vaccine, but it will not be available until after the traditional end of the flu season.
The number of confirmed cases in Australia was approaching 10,000 today. There were around 3000 new cases detected in the last week, after just over 6000 were diagnosed in the first months of the swine flu scare.
A fifth NSW resident was confirmed to have died from the disease, taking the national death toll to 20. A further 32 NSW residents are in intensive care, at least six of them young and otherwise healthy.
"There's good evidence from overseas and emerging in Australia that some fit, healthy young people who contract the disease can deteriorate rapidly with respiratory difficulty, and if this happens then they should seek urgent medical attention," Australia's chief medical officer Jim Bishop said.
The latest victim was a 55-year-old man with underlying health problems who died in St George Hospital.
Medical professionals are now bracing for a possible stronger, deadlier version of the virus next winter, just like the Spanish flu that wiped out millions of people across the world after World War I.
The World Health Organisation (WHO) labelled the A(H1N1) pandemic "unstoppable", but the immunisation rollout in Australia is not expected to begin until October.
Influenza Specialist Group chairman Alan Hampson said he would not be surprised if swine flu continued to infect people after September, when the normal flu season usually finished.
"In historic terms, we still haven't really seen it play out its full course," Dr Hampson said on ABC Television. "It's still in its early stages. As we get more fully into the southern hemisphere winter, we might see some changes in the virus."
Thousands of deaths
Computer modelling by University of Western Australia pandemic experts revealed that unless there was a widespread vaccination program, 27 per cent of the population would get swine flu.
The Federal Government had already requested the avian flu modelling conducted for WHO by Professor George Milne, on which the new research was based. "In our simulation we estimated it was 27 per cent," he said of the new data.
According to the official NSW Health influenza pandemic action plan, an infection rate of 25 per cent means 10,000 people could die within two months in NSW alone.
"As there are about 45,000 deaths per year from all causes in NSW, a 25 per cent attack rate could therefore result in more than double the usual number of deaths over a two-month period," it said.
Infectious diseases and epidemiology expert Professor Raina MacIntyre, part of the influenza scientific advisory group to the Commonwealth Chief Medical Officer, backed the figures.
"That's certainly in the ball park," she said of the 10,000 potential deaths - 10 times the usual number of flu deaths in a whole year.
NSW Health sought to play down the threat, and said early indications were that swine flu was not as severe as other strains.