A sick metaphor plagues us

Infectious illness is spreading, but talk of a diseased society carries added dangers, says David Bodanis

The latest World Health Organisation report on the spread of infectious diseases started sensibly enough, describing the resurgence of tuberculosis and diphtheria and other traditional diseases; the appearance of new infections such as the Ebola virus, too. But then Dr Hiroshi Nakajima, the director-general, began to get excited. "We ... stand on the brink of a global crisis in infectious diseases. No country is safe from them, no country can any longer afford to ignore their threat."

The report goes on emphasising the dangers for Africa and poor countries generally, and suddenly it's clear that we're in the world of the infection metaphor again; the long-standing and powerful image, where dangerous spreading entities are on the loose. Not just microbial ones. Oh no, those are just the barest visible signs. There is something deeper, some sort of political danger, a social danger: an attack from without, by tiny threatening objects, which - unless blocked - will gush in and undermine and destroy us.

Louis Pasteur helped to consolidate this idea in its modern form. He strongly detested and feared microbes. One of the sole surviving accounts of dinner at his home described the mortified silence of his wife and guests as the great man peered close at all the glasses and empty plates to locate any possible intruder. Pasteur equally detested the urban mob.

The mob was also a collection of potentially infectious creatures that decent people couldn't ordinarily see, but which was always there, ready to pounce, to subvert our inner structure, have us collapse in disorder and turn us into - the worst of all possible fates - a thing no different from the seething mass that had attacked.

Rather than being just an individual quirk, which Pasteur's guests could nod at, smiling politely, waiting until he had stopped his harangue, and they could get on with dinner, this idea of the infectious masses quickly resonated in society. Europe was changing, fast, through invisible forces that no one could quite understand. Yet here was a top scientist, showing that when the same thing happened in our individual body it really did have a clear cause: these foreign intruders, knocking our normal constituents apart.

Humans naturally think through metaphors, and the parallel of our physical body with the larger body politic is an especially recurrent form. It was only natural, accordingly, to view society through the lens of this microbial image.

At home, the urban working classes became seen as even more dangerous than before. It was no longer that they might simply erupt in fits of violence, causing mob riots that might briefly damage the wealthier quarters, but rather that they might organise themselves into some sort of anti- society, powerful enough truly to take over.

On a wider scale, the Jews - once again - were seen as an especially suitable target. Whenever there are subtle and invisible problems, such as economic slowdowns or vanishing jobs, what could be more fitting than to match that with a group that seemed equally subtle and invisibly linked up?

And then, stretching even further away, there was the world of the distant colonies; the swarming foreign hordes that had to be controlled, and held down, and especially - the alternative was too terrible to imagine - kept from ever surging back towards the imperial homelands in large numbers on their own. Kitchener's forces at Omdurman in 1898 were regularly described as taking the field against a huge number of bacteria, worthily eliminated by his army's machine-guns.

It all got stronger in this century. Who can expect restraint from a microbial enemy? As the liberal New Statesman wrote, at the start of the First World War, "One desires the utter destruction of this evil thing [Prussianism], which has little scruple, as one desires the end of an epidemic of scarlet fever."

Later, anti-Communist views naturally took this approach. Lenin was a "bacillus" who had to be transported across Europe in a sealed train; then there would be a cordon sanitaire to keep that new entity he had created from surging back across the steppes.

The underlying notion was that the people who were touched were inherently dangerous and that the individuals at home actually could be susceptible to this awful thing, and switch from their well- ordered state, if they, too, received any contacts.

The most extreme case is well known. Isaac Baashevis Singer describes, as a Hassidic boy in German-occupied Warsaw during the First World War, having his street suddenly surrounded. Armed German soldiers led out all the Jews, women and children included, They were herded to special reception areas - their clothes removed and replaced by simple gowns - and then led in great confusion and with children crying to large "spraying" rooms where they were ... merely dusted with powder to remove the lice and bacteria that were on their bodies. (Typhus actually was a problem and could otherwise lead to infection for the Germans in these freshly occupied lands). A quarter of a century later, the conclusion was entirely different.

And now? A distaste towards foreigners, and of poor countries in particular, easily encourages a view of them as carriers of disease; as somehow, by their mere existence, the source of all our woes. In the WHO's list of the top 10 infectious diseases, Aids, which could directly affect wealthy Westerners, comes about fifth; the higher ones were pneumonia and dysentery and their like, which are unlikely to affect us directly.

Dr Nakajima's warning against the threat of infectious disease closely parallels phrasing about the threat from Africa and Third World immigrants. Here, too, every nation is generally described as being at risk; here, too, only the right defensive measures, taken early on, can keep us protected. For microbes it will be labs, international surveillance, hygiene controls. For immigration it will be similar: computer checks, passports, tougher borders.

It is distressing how unchanged the terms are over the years. George Kennan, in his original article proposing the containment policy against Communism, describes the danger in terms Pasteur would have recognised: "We have seen that Soviet power is only a crust concealing an amorphorous mass of human beings."

In the generally liberal Atlantic magazine recently, a half-century later, Robert Kaplin was similarly horrified: "In cities in six West African countries I saw similar young men everywhere - hordes of them. They were like loose molecules in a very unstable social fluid, a fluid that was clearly on the verge of igniting."

What would have happened if actual bacteria didn't exist on our planet, or hadn't been discovered. Would our view of each other as potential bursting- out swarms have been so common? It's impossible to tell.

Perhaps the infection metaphor will continue wherever otherwise inexplicable social changes are taking place. Certainly its utter flexibility helps. How else could Iranian mullahs declare that satellite dishes must be banned to keep out the infection of Western ideas, just as the mayor of a Paris suburb decided that his district's satellite dishes must be outlawed to protect it from the virus of Islamic fundamentalism?

The writer lectures in social theory at Oxford University.