Simon Jenkins's distaste for scientists leads him to declare that they deliberately overstate risks, and make panic predictions (Swine flu was as elusive as WMD. The real threat is mad scientist syndrome, 15 January). In reality, scientists worked calmly – not "frantically" as Jenkins asserts – to predict the progress of the disease and to understand risk.

Jenkins says of the initial predictions about the spread of swine flu: "The chief medical officer, Sir Liam Donaldson, bandied about any figure that came into his head, settling on '65,000 could die', peaking at 350 corpses a day."

Worst-case predictions are not figures plucked out the air "to convey plausibility", but result from well-researched computer simulations. Margins of error are high; no one pretends otherwise. Yet Jenkins is delighted when a worst-case scenario isn't met, as though he were right and everyone else wrong.

There is a genuine debate which we must not overlook. What should the government response be? Does the risk justify the expense of stockpiling vaccine? Is it right to divert funds away from other health matters? But Jenkins doesn't ask such questions – instead he dismisses it all as "hysteria". Reasonable advice – alerting morgues, identifying vital key workers – is denounced as "drivel".

You could argue that media coverage of H1N1 was excessive and that editors think the biggest numbers make the best headlines. But the scientific process has been evidence-based and transparent throughout. At the Science Media Centre we have tried to ensure that responsible journalists have had access to the best scientists. We've seen lots of co-operation and very little hysteria.

Science moves by small steps, and as we learn more the picture becomes clearer. This is how official advice on Tamiflu for children was revised. Each time a risk comes along we are better prepared to characterise the next one. But decisions still need to be made early. Picture a beleaguered Simon Jenkins in the middle of a deadly pandemic, decrying the government's woefully inadequate response and failure to order enough vaccine.

It's embarrassingly straightforward. Viruses usually don't mutate into major killers; that's why there are still people left on the planet. But it has happened before and will happen again. We can't predict when – that's what risk is – but we can perform the analyses, educate ourselves and be prepared, all underpinned by evidence drawn from virology and epidemiology. Or we could shrug and say it's all hype, and most of the time we'd be right. Similarly, most of the times I put on a seatbelt I don't crash my car.

Jenkins's logic goes as follows. Once there was a boy who cried wolf, but there wasn't a wolf. Therefore not only do wolves not exist, but there must be a conspiracy between wolf experts, the lupine risk assessment board and the manufacturers of bite-proof trousers to convince the rest of us that they do.

With swine flu there wasn't conspiracy and hype; just scientists, patiently performing the analyses, and explaining the possibilities.