Saturday 15 October marked the fourth annual Global Handwashing Day, and in schoolyards across the world, in Peru and Bangladesh, in Ghana and Pakistan, Egypt and Ethiopia, 200 million people, most of them children, gathered in a great act of communal handwashing: lines stretched across courtyards, tiny hands pressed beneath taps, a flurry of soap, water and lather.
Global Handwashing Day is a multi-organisational initiative, launched to convince us that the simple act of washing hands with soap can reduce the spread of often fatal diseases and acute respiratory infections. Its organisers estimate that hand-washing with soap could save more lives than any single vaccine or other form of medical intervention.
Encouraging people to wash their hands after using the toilet or before handling food might seem like stating the obvious. But the truth is quite disturbing: people lie – and lie quite spectacularly – about their personal hygiene.
A recent study by the London School of Hygiene and Tropical Medicine and Queen Mary, University of London found that while 95% of us claim to wash our hands after going to the toilet, only 10-12% of us actually do so. And our soap-dodging has some unsettling repercussions: one in six UK mobile phones, for instance, is contaminated with faecal bacteria, which can survive for hours on hands and surfaces, transferring to everything we touch.
In a timely collision of events, the film Contagion, a Hollywood blockbuster about an incurable virus spread by a single touch, was released last weekend. "The average person touches their face three to five times every waking minute," Kate Winslet's character intones in the film's trailer. "In between, we're touching the door knobs, water fountains, and each other."
Contagion's story seems fitting in a world that is somehow simultaneously obsessed with germs yet strikingly nonchalant about hygiene. How is it that our society lives in fear of swine flu and bird flu, is so smitten with antibiotics, Cillit Bang and antibacterial chopping boards, yet the vast majority of us do not even bother to wash our hands after we have been to the bathroom?
You can tell a lot about a nation from its public toilets. In the UK we are increasingly following the lead of America, where for years public restrooms have been catering to a growing sense of germ phobia: plastic covers that scroll across toilet seats with the wave of a hand, automatic flushes, automatic soap dispensers, automatic taps, and state-of-the-art hand-driers. Many take their fear of public toilets even further: women making nests of toilet paper to cover the seat or choosing to "hover" rather than actually sit down; where an automatic flush is not available, some people use their foot to press the lever.
That the toilet door might well have more bacteria than the toilet seat is in many ways irrelevant, since this behaviour is motivated not by reality but by the perception of dirt. In truth, many shared bathrooms are cleaner than, say, the telephone on your office desk, your computer keyboard, the dishcloth by your kitchen sink, or your mattress at home, accumulating nightly a steady weight of dust and dead skin and mite detritus. In many ways this is wholly understandable; faecal bacteria spread easily, reproduce quickly and can lead directly to illness. And it is perfectly natural, perfectly logical, that we expect them to be congregating in greatest numbers somewhere around the toilet bowl: silent, invisible, potent.
"If you want to understand why people feel the way they do about contagion, you have to look at our evolutionary past," says Dr Val Curtis, of the London School of Hygiene and Tropical Medicine. "We have an innate disgust towards germs, these tiny near-invisible things, in the same way that we have an innate fear that helps us keep away from large predators. So our behaviour, at a subconscious level, is driven by disease-avoidance."
Curtis lists the seven categories of disgust she and her colleagues have identified in human behaviour, ranging from our disgust at the threat of contagion, to the sight of wounds, bodily fluids, rotting foods, physical deformities and the moral disgust we direct towards those who violate our moral codes through cheating, lying or abuse. All of these are rooted in our desire to avoid contamination, she explains. "Disease and disgust weave themselves right through society."
The desire to keep clean is not confined to humans – Curtis points out that birds keep their nests clean, lobsters don't go into the nest of another lobster if it is ill, tapirs have latrines, chimps wipe their penises after sex, and primates groom. But the difference is that mankind has the ability to invent Domestos and antibacterial soap. If previous generations were not as clean as we are, it is only, Curtis argues, because they were unable to be. "There is a human propensity to want to avoid dirt, and now we have been able to build the world that we wanted. If cavemen could have had a white-tiled bathroom, they would."
But today we also have more stimuli to augment our fear of infection. Curtis points to the recent case of swine flu, an outbreak covered widely in the media, and how as a result handwashing at service stations doubled during the epidemic. The flu epidemic that has recently affected Australia, and is therefore destined to reach our shores this winter, will likely prompt a similar burst of public cleanliness.
Naturally, the manufacturers of cleaning products also capitalise on these fears, encouraging us to buy more products, and funding academic research into the best ways to defeat germs. The Hygiene Council, for instance, is funded by Reckitt Benckiser, the makers of Lysol, and even Global Handwashing Day, though a responsible initiative supported by the Centers for Disease Control and Unicef, is also backed by Procter and Gamble, Colgate-Palmolive and Unilever. After all, if the essential message is to wash your hands with soap, someone has to provide the soap, right?
Occasionally, the science doesn't quite do what is hoped – a study in Pakistan, for instance, funded by a leading soap manufacturer disappointingly found that antibacterial soap was really no more effective at cleaning hands than normal soap. And for all mattress companies' talk of dust and mites and replacing your bedding, there is no hard evidence that dust mites spread illness.
Harsh chemicals may indeed have their own unwanted consequences – a study by University College London's Institute of Child Health concluded that strong soaps, beauty products and biological washing powders strip away the skin's protective outer layer, leaving people more likely to develop allergies.
And anyway, isn't a little bit of dirt good for us? Though Curtis is adamant that washing hands after going to the toilet or changing nappies is of paramount importance to stop the spread of dangerous bacteria, she also speaks of happily eating unwashed vegetables from her own garden. Some people believe there is weight in the "hygiene hypothesis" – the theory, first proposed more than 20 years ago by David P Strachan, professor of epidemiology at St George's in London, that limiting children's exposure to bacteria and parasites early on in life will lead to a greater likelihood of allergies, asthma and autoimmune diseases when they are older. In fact a study by the Laboratory for Human Biology Research at Northwestern University found that children exposed to more animal faeces and suffering more cases of diarrhoea before the age of two had less incidence of inflammation in the body in later years.
"Ever since the development of germ theory in the 19th century, with Pasteur and Lister, there came the link between bacteria and disease," notes Kate Forde, curator of the Wellcome Collection's recent exhibition on the subject of dirt. "From then on, the body was the site of a battle between germs and disease, and I think that's something that's still very vivid in our cultural memory – even though the idea has become more nuanced and these days we're aware of things like "good bacteria", and even though some scientists believe that we are cleaning our environs too harshly and that this is leading to a rise in things like asthma, you still have all these ads on TV that talk of 'waging war on dirt and germs'."
"But it's a complex issue," she adds. "It was the anthropologist Mary Douglas who said: 'There is no such thing as absolute dirt. It exists in the eye of the beholder.'" Indeed Forde points out that in 19th-century London, "dirt" was potentially lucrative, and people sifted through the city's detritus, through dead cats, bones and broken pottery, seeking a way to make money – a practice immortalised by Charles Dickens in the character of Noddy Boffin in Our Mutual Friend, who earns his living scouring dust heaps.
"And in the 17th century the Delft scientist Antoine Van Leeuwenhoek, working before germ theory, would scrape the plaque from his teeth," Forde says. "He was so incredibly excited by this dirt, he was entranced by all these little creatures he was seeing down the microscope, and he saw them as proof of God's creative world."
While Curtis argues that our desire for cleanliness is a fundamental human instinct, a hardwired method to avoid disease, our disgust with the idea of dirt is something that seems to have grown rapidly in recent times. If you look at the ways in which our society has changed in the last century this is perhaps not too surprising. Over the past few decades, even as the global population has grown, we have seen an increased physical distancing from one another.
Viewed in another light, Contagion could be seen as a film about our increasingly atomised society as much as one about the spread of disease. "Don't talk to anyone, don't touch anyone, stay away from other people," says the film's trailer. But isn't that what we're doing anyway? A growing number of us now choose to live alone, to avoid our neighbours, to remain untethered to the area in which we live. Furthermore, in a world of email, text, video phones and social networking, our interaction with other people is increasingly virtual, and physical human contact grows ever more unfamiliar.
Arguably with this isolation comes a growing sense of disgust – a fear of contagion through contact with others, a squeamishness about all of the fluids and flakes of the human body. It's worth noting that in Contagion, Gwyneth Paltrow's character contracts the lethal virus while on a business trip to China, where she is cheating on her husband, before unwittingly bringing the virus back to the US. Her infidelity is an interesting element to the tale here, because it allies moral disgust with the spread of infection.
We seem increasingly to view infection as a threat that comes from outside ourselves, that is foreign and other, rather than a matter of personal responsibility. Curtis notes that the automated public bathrooms we see in airports are reflective of our fear of foreign bodies and infection from abroad. She also observes that some people may be so subconsciously repelled by the idea of contracting a foreign disease that they seek to minimise their time and contact with surfaces in the public bathroom by skipping hand-washing altogether.
In her studies of service-station toilets, Curtis found one of the most effective ways to persuade people to wash their hands has been to put up signs by the sinks that read: "Is the person next to you washing their hands?" In these studies, people felt shamed into washing their hands themselves.
Perhaps it is time we began to direct more of that shame towards ourselves. Our disgust with the very idea of dirt and of waste has meant that we are no longer dealing with it responsibly. Forde speaks of becoming intrigued by the idea of landfills – "how far away from us they are, so they have this invisibility" – and tells of the American artist Mierle Laderman Ukeles who has taken it upon herself to shake hands with every sanitation worker in New York. "The point of that is trying to remind people that they are connected to waste, that we create waste, even every time we so much as breathe out, so we ought to have a more honest, realistic approach to it."
Similarly, Curtis admits that last week's mobile-phone study was specifically publicised in a way to "gross people out – because disgust is the best way to get people to wash their hands". In recent times our disgust has been focused elsewhere, on foreign infections, on the strangers in public bathrooms, but now it is high time we reconnect with our own dirtiness, that we grow just a little bit disgusted with ourselves. Because, as Curtis notes: "The thing you have to remember is that the dangerous bugs are inside you."