Over the past three or four days, the news about swine flu has ramped up and up and up. On Monday I watched the headlines for the very same story get more powerful and frightening, moving from flu-in-Mexico to “Doctors brace for flu pandemic” in about six hours.

It’s not that the mass media has been outrageously sensationalist; after all, editors do have to sell newspapers and to some extent they are only responding to the ramping-up that’s happening in the halls of government, where politicians and some health officials have upped the ante, moved the response systems to the next number up and spoken grave warnings that sound great in a lead article.

Nonetheless the headlines and politicians between them are almost certainly ramping up to way past the point justified by the actual event.

The problem for everyone is — will this be the once-in-a-hundred-years flood (or, in our part of the world, the once-in-several-centuries-tsunami)?

And the answer is, almost certainly not.

Firstly, such events are incredibly rare, by definition. Secondly, the data so far — especially the low virulence reported in cases outside Mexico — doesn’t look that bad.

Not that you’d know that: as happened in the case of SARS six years ago, the media reports only the total number of cases (or suspected cases, even worse), not the daily incidence rate. That may well be declining by now, showing that the outbreak is already half over.

And thirdly, with any luck our surveillance and response mechanisms are going to be good enough to ensure that events like this or like SARS can almost always be nipped in the bud fast enough to prevent them from developing into Big Ones. As indeed they are proving to be so far.

The current heavy scrutiny of travellers is simply public health deliberately erring on the cautious side, making sure they’re on top of everything, just in case. I bet most members of the public, reacting to the headlines, think erring on the cautious side is a good thing, too.

The problem is, that there are significant costs for intervening too much. The most obvious costs are economic. In Canada, the SARS outbreaks in 2003, which in the end were completely confined to hospital settings and posed no risks to the general public, decimated the travel, tourism and hospitality sectors.

That’s not just numbers: that’s jobs lost, houses lost, marriages broken, dreams crushed, tax dollars unavailable for health and education. 25 000 people were quarantined unnecessarily, which was enormously socially stressful and exhausted the public health workforce.

There were many people who did not get to farewell loved ones (who died alone of their cancers, heart attacks etc) because hospitals 400 miles from the outbreaks introduced no-visitors policies or because emergency facilities were unavailable out of fear of infection.

Since we don’t actually know whether quarantine is effective or not — we do know that those expensive thermal scanners are almost guaranteed to be a complete waste of time and money, not that you’d know that from the media or from public health officials — we need to be really really sure we want it before we incur all the costs of having it.

No wonder most expert commentators, in sharp contradistinction to the headlines, are adopting a stance of “be alert, but not alarmed”.

People — both experts and lay people alike — are going to over-react because our brains are all cognitively wired to perceive risks in certain ways.

Risks look scarier when people feel they aren’t in control (individually or by proxy — eg, when “science” isn’t in control either), when the risk kills lots of people all at once rather than one or two at a time (which is why air travel can seem riskier than car travel, even though more people die on the road than in air accidents), or as a result of prior experience (for example, if you’d worked in a Chinese hospital during SARS, you might be more worried about swine flu now).

When risks look sufficiently severe people don’t calculate the pros and the cons. Instead, they try to remove or control the worst case scenario, even if it’s really unlikely. It’s called decisional regret.

No public health official could bear to think that a pandemic occurred because they didn’t act cautiously enough. So they’ll put in place the unwarranted quarantine requirements, just in case, no matter at what cost.

The same feelings drive people to go buy limited stocks of Tamiflu and cancel their holidays. ‘The chance is small, sure — but (usually looking at your kids) what if …?’

Good communication is the key to successfully managing a health crisis of any sort, to navigate a path of minimal harm between under and over reacting.

Mostly that path is being taken. Telling Australians to wash their hands is good advice because it helps protect against all kinds of illnesses and gives us something we can do.

It is this sort of unglamorous, low key investment in the community that is often overlooked in pandemic planning, in favour of high-drama medical solutions like quarantines, vaccines and drugs.

It’s actually our friends and neighbours who save most lives in many disaster situations, and who are likely to do the most damage control in the event of an actual pandemic: caring for kids, nursing the sick, helping out with chores, sewing face masks, making quarantine liveable, enforcing basic hygiene.

I’d like to see their contribution get all the unwarranted coverage currently being given to the numbers of the sick.