The number of swine Flu cases at time of writing is > than 100 but health authorities are urging people to remember that most cases have been mild. So far in Australia the rate has only spread very moderately. Dr Jodie Mc Vernon from Melbourne’s population health departments warns it is unlikely the disease will remain mild and the spread contained.

As most of the population have no immunity to swine flu, unlike the ordinary seasonal flu that affects 10% of the population, swine flu is likely to affect up to 40%. Particularly younger people. And when the illness infects another person it doesn't make a "perfect copy" of itself, so every now and then it may mutate into a more severe disease, she said.

Professor Adrian Sleigh from the Australian National University's epidemiology department agreed people shouldn't over-react.
“Seasonal flu caused about 250,000 deaths worldwide a year, he said.
So far, there have been 97 deaths from swine flu around the world.”
http://www.medicalsearch.com.au/News/VicDont_panic_over_swine_flu_health_experts_are_urging-38861/