THE SIGNS OF INFECTION ARE alarming. First, there is the quiet circulation among scientists of the idea that a significant outbreak of influenza. might be overdue. This is stoked by reports from East Asia of a ferocious strain of bird flu hurdling the species barrier and slaying more than half the people it infects. The death toll lingers in the low hundreds and there is a possibility that there might be human-to-human transmission; the World Health Organisation (WHO) urges countries to review their preparedness for a pandemic.

And so the concept of a devastating flu pandemic escapes from the laboratory into the wild, infecting politicians, pundits and the public. Britain’s chief medical officer declares that tens of thousands will die. What happens? Tens of thousands of healthy Britons clamour for the annual flu jab in the mistaken belief that it will protect them against bird flu. Now there comes The Monster at our Door, by Mike Davis, a slip of a book screaming that avian flu is a “viral asteroid on a collision course with humanity” capable, possibly, of extinguishing a billion lives. When cultural commentators and “urban theorists”, as Davis styles himself, catch the bug, we are truly witnessing the full-blown version of pandemic paranoia.

My introduction aside, bird flu is one of the few things that keeps me awake at night. Nature is a more capricious terroriser of humanity than man; she has devised numerous diseases that continue to defeat modern medicine (malaria, HIV). She manifests her evil genius by ensuring that people are infectious before they look or feel ill — they are, in the sinister terminology, a “silent reservoir” — thus turning the irresistible urge for a mother to kiss her child into a weapon of infection. No terrorist can match that, nor the horrendous death tolls of the Black Death (estimated to have killed one European in four, and half of London, in the 14th century), the 1918 outbreak of Spanish flu (40 million upwards) and malaria (up to 2.7 million annually, most of them African children).

The H5N1 circulating in birds at present is exceptionally pathogenic — to birds and the few humans who have caught it. People have no natural immunity to bird flu, especially this one; those with H5N1 more often than not don’t pull through. As the strain circulates ever farther, it could mix with human flu and, in a molecular shuffling of the genetic decks, spit out a killer virus combining the lethality of bird flu with the high transmissibility of human flu.

So, I have some sympathy with Davis’s warning that we could be facing a disaster that mankind is ill-equipped to face. He documents in gripping fashion — he is, after all, a historian — the appalling culture of poverty and political secrecy that allowed H5N1 to flourish unchecked in South China and spread elsewhere. The virus is no longer a reassuringly remote nightmare, contained within Asian borders — its talons have scratched parts of Europe and it has claimed parrots in British quarantine. Migratory birds are likely to stretch further the global reach of H5N1.

But Davis also detects more evil besides, such as growing urbanisation. “The great concentrations of urban poverty in Dhaka, Kolkata, Mumbai and Karachi are presumably, like so many lakes of gasoline waiting for the spark of H5N1,” he thunders, although the means by which one would stop the stampede from poor villages to rich cities eludes him. He berates greedy pharmaceutical companies for keeping the door of the medicine cabinet firmly shut, and for focusing on profit rather than wiping out disease. I’m no apologist for big pharma, but isn’t profit their bottom line? Isn’t it the duty of governments, rather than industrialists, to protect citizens?

I’m not sure that Davis has his priorities right. If you talk to most flu experts they are far more worried about surveillance and containment. East Asia, as we have seen, does not have the money or infrastructure to build an effective flu firewall, nor does the West seem willing to provide the means for this to be done. We don’t know what a pandemic virus might look like — should we manufacture a vaccine for today’s strain when a significant outbreak might be years away? There is also no guarantee — although to say so would spoil his thesis — that humankind is about to sneeze to death. In the case of many viruses, the more widespread they are, the milder they become. Sars didn’t finish us off, although there is no excuse for complacency.

I’m also wary of a book whose first line serves up a questionable statistic. Davis suggests that 40 to 100 million people may have died in the 1918 flu outbreak; the WHO states it is “at least 40 million”.

Davis offers a good scare story, although it frequently degenerates into B-movie cliche. “As the hour hand on the pandemic clock ominously approaches midnight . . .” begins the opening line of his portentous closing paragraph. But I wish this book had been written by a flu scientist. I also find Davis’s principal analogy — bird flu as “viral asteroid” — unfortunate. Despite the apocalyptic predictions, the killer asteroid has yet to come knocking.

Anjana Ahuja writes the Science Notebook column in The Times every Monday

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