Swine flu’s birthday: Should we have reacted differently?

The worst case predictions are not plucked out of thin air, they are made on the best influenza research available – but we can’t predict exactly what will happen and looking back, what struck me most about what the experts said at this time last year is how often they said “we don’t know”.

Science moves in small steps and each time a new threat comes along we are better prepared to characterise the next one.  And when it comes to infectious diseases, if we “don’t know”, then I am a big believer in preparing for the worst.

The H1N1 swine flu virus is potentially still evolving but how it will evolve and change is something we can’t easily predict. Remember that out there somewhere, still circulating, is the H5N1 avian influenza, otherwise known as bird flu.

This virus is still infecting people and still killing between 50-60% of people it infects. If that virus or another were to become readily transmissible from human to human and keep its nasty ability to kill very large numbers of people we would have a disaster on our hands, far from crying wolf we would have on our hands a wolf with savage fangs that would tear us to shreds. So are we getting any better at identifying aggressive flu strains?

According to Alan Hampson the Chair of the Australian Influenza Specialist Group: “We are far from being able to read influenza viruses like an open book. While we do have some clues as to the factors that make that such a nasty virus, I don’t think we will have that completely defined in a way that would allow us to take a new virus and immediately say that this is going to be a mild virus or a terribly severe virus except for watching what is happening in the population.”

Alan also suggests we are a long way from being able to just look at the virus itself and predict how severe it is going to be. “There are a number of factors that are involved in how severe a virus is likely to be in a population. This H1N1 was a little unusual in that it had a degree of relatedness to viruses that older members of the population may have experienced way back in the past. It might have been the thing that saved it from becoming a more widespread infection,” he said.

The other big challenge is identifying everyone who contracts the virus so that the number of people who die can be put into some perspective to work out how deadly the new strain really is.

Unfortunately this is an area of huge uncertainty. I’m pretty sure I had swine flu last year, was it reported?  No.

I just felt rotten and stayed at home for a few days.

The other big area of uncertainty is who’s most at risk. Dr Ian Seppelt, an intensive care physician who was at the front line of swine flu says one-third of all the people who ended up in intensive care with swine flu last year were apparently healthy people with no underlying illness.

Far from being mild, he saw large numbers of people with influenza passing through intensive care and warns that “if we had twice the case load, or even probably 1.5 times the case load the system could not have coped and it would have led to more difficult triage decisions, including refusing intensive care admission to people who were less likely to do well and that’s the sort of decision we’re not so used to making, but would have to make if there is a future epidemic that is more severe.”

So just because we cried wolf, and the wolf did not savage us all to death, does not mean there wasn’t a wolf or that wolves don’t exist and that we shouldn’t be ready for the next one.