8

Our microbes, our selves

Lave tes mains souvent, tes pieds rarement, et ta tête jamais. (Wash the hands often, the feet rarely, and the head never.)

Provençal saying

‘Mechanics contact a lot of irritants in their work. Just about everything they use is an irritant. Fuels – petrol, oil, diesel – and brake fluid. They often use kerosene for cleaning motor parts. They dip their hands in the kerosene to get the parts out. But in fact, mechanics don’t contact many allergens. A lot of these products are long-chain hydrocarbons, not the kinds of chemicals that cause allergies. What they do get allergic to are their gloves, their liquid soaps and their hand cleaners.’

Associate Professor Rosemary Nixon, a Melbourne-based occupational dermatologist, is talking about what she does.¹ She has decades of experience looking at work-damaged skin: the skin of people who get their hands dirty in the course of a day. Or who, by wearing gloves while they work and using copious soap after they take them off, try not to. It’s probable that she knows more about the mechanics of mechanics’ work than most of her fellow dermatologists. She assesses the minutiae of the many jobs most likely to be affected by allergic or irritant contact dermatitis – floor finishers, hairdressers, dental technicians, bakers and pastry chefs, mechanical engineers, factory workers, printers and metal fitters. And, closer to home, nurses.

Nixon stands at the intersection of doctors’ white coats and workers’ hi-vis gear (or aprons, smocks, scrubs, gloves and other protective clothing). She is a much-published and highly renowned authority on skin patch testing for allergies, but is so down-to-earth I suspect she isn’t afraid to get her own hands dirty, metaphorically at least. She seeks to understand what people do in their jobs, and why it is making their skin suffer. What she often finds is that skin reacts to the very things that are supposed to protect the body from chemical, microbial and viral contaminants, because these fabrics and formulations are chock-full of allergens and irritants themselves. Adverse reactions may also be symptomatic of the way we live now, beyond the workplace, in our air-conditioned offices and schools, sanitised kitchens and bathrooms, with our fire-retardant sofas, carpeted bedrooms and neatly hedged and mown yards.

Mystery rashes might not be sexy, but Nixon’s case histories are riveting, with more closure – and less tragedy – than those of the late neurologist Oliver Sacks or surgeon Atul Gawande. She recounted the case of a fast-food cook who was experiencing contact dermatitis that no doctor she consulted could figure out until she made her way to Rosemary Nixon’s clinic. ‘It was so patchy,’ Nixon says, ‘it was hard to explain where the rash was. But we got her to bring in her frying basket to the clinic.’ I imagined the patient holding this chip-fryer in the waiting room, surrounded by others holding hairdressers’ bottles of shampoo and dye, bakers’ sacks of flour, and floor sanders’ vats of epoxy resin, although smartphone photos and videos largely make these props redundant. Nixon reveals, ‘We found out that the coating was corroded, exposing the nickel underneath. When this woman held the basket, we saw that was exactly where the rash was.’ Nickel allergy is common, so a properly sealed basket would solve the problem.

There was a carpenter who worried he was allergic to the nails he used in his work. It turned out his problem wasn’t the nails but the onion he chopped to cook his dinner every evening. I got the impression that Nixon learns a lot about her patients’ lives beyond their skin conditions when she explained that this man had had to get into the habit of preparing his own dinner after he and his wife separated. It felt like the first chapter of a melancholy novel. Then there was the racehorse trainer who feared dermatitis on his hand meant he was allergic to his thoroughbred. This man confessed he’d rather be allergic to his wife than to his horse. Luckily for all three living creatures, he was allergic to neither. The culprit was ranitidine, a veterinary medicine that he dispensed by syringe, gloveless, into the horse’s mouth before heavy training.

Dr Nixon reflects on skin epidemics that most people have never heard of. One, however, coincided with a well-known scourge. ‘When HIV emerged and universal precautions came in to stop infection, suddenly there was a huge demand for latex gloves. Everyone had to wear them. When I went through as a young doctor, we never used gloves for putting in drips and things like that.’ Medical gloves in the 1980s and 1990s were powdered latex ones, made with high levels of protein, which many wearers became allergic to. Nixon recalls lots of cases of this. ‘I remember one nurse who had rhinitis [hay fever] for eighteen months. She was taking antihistamines whenever she went to work. She’d had terrible experiences before I saw her, and we realised her symptoms were related to a latex allergy from the gloves she was wearing all the time. She had visited her GP and gone into anaphylaxis because of all the powdered latex in the air. She was rushed to the hospital. There, in the emergency department, she was descended upon by doctors. What were they all wearing? Latex gloves. It was a bad time.’

Dr Nixon alerted me to one of the first documented cases of a work-related cancer cluster, still shocking centuries later, which manifested on the skin of eighteenth-century chimney sweeps in England. This story is more Les Misérables than Mary Poppins – poor, often orphaned young boys, some as young as four, so they were small enough to fit into narrow chimney flues, were put to work with their brushes. According to an article published by The Lancet in 2019, ‘Poor hygiene conditions at the time meant that these children would bathe normally once a year and would often work naked, repeatedly exposing their skin to toxins in the chimney soot.’ Many of these children developed scrotal squamous cell carcinomas as adults. The condition became known as chimney-sweeps’ cancer, or Pott’s cancer, after surgeon Percivall Pott, who realised that many Londoners with testicular cancer had one thing in common: they had all worked as chimney sweeps as children.² Pott died in 1788, the same year the British parliament passed a reform he had campaigned for, the first Chimney Sweepers Act. It set a minimum working age of eight years old but, unenforced, the law was roundly ignored.

The hyper-clean twenty-first-century city-dweller who showers before leaving home, after the gym and again in the evening to freshen up after a day in an air-conditioned office, might take a moment to dwell on The Lancet’s phrase, ‘would bathe normally once a year’. We know about Roman baths, Turkish hammams, Japanese onsen, the pre-Columbian baths of Chapultepec in Mexico and mass bathing in sacred Indian rivers. Yet in Europe, up until the late eighteenth century there was a widespread view that filth on the skin could be protective and that water on the skin, even as a cleansing agent, was bad. French historian Jules Michelet’s pithy description of the European Middle Ages as ‘a thousand years without a bath’ is repeated often.³ Nevertheless, given that cleansing baptismal waters are central to Christianity, that places of pilgrimage are often sites of holy waters too, and that thermal spas are scattered across the continent, this European aversion to water surprised (and slightly revolted) me.

Peter Ward is a Canadian historian of bathing with a perhaps inevitable subspecialty in the history of soap. He writes that as early as the twelfth century, some medical texts endorsed bathing as curative with the aim of healing, rather than cleansing. Public baths went into steep decline after the fifteenth century, their popularity stymied by rudimentary plumbing and insistence on modesty; the shame associated with nudity made a regular scrub-down unthinkable. A further hindrance was a fundamental misunderstanding about skin’s basic barrier function, its miraculous ability to keep what’s inside in and what’s outside out.⁴

Washing had been about laundering the white linens worn against the skin, rather than cleansing the skin itself. Over time, however, bathing became central to the pursuit of hygienic, germ-free living. Cleanliness also became a marker of social identity and status. Bathing was first taken up by the urban bourgeoisie, generating the term ‘the Great Unwashed’ – everyone else. English reformer Edwin Chadwick told an inquiry into the sanitary conditions of the English working class in 1842 that a Lancashire collier had said of his peers, ‘They never wash their bodies underneath; I know that; and their legs and bodies are as black as your hat.’⁵ Skin was starting to be seen not as sponge-like and porous, but non-penetrative and protective. It required washing, whether in private bathrooms or public baths. But it took some time, centuries in fact, for everyone to immerse themselves in this idea.

Claudia Benthien, a scholar of literature and culture, considers the beginning of this shift in the late eighteenth century by way of changing perceptions of dirt. She writes that during this period, we saw the ‘gradual shift of the dirt boundary from the inside to the outside . . . It was the threat of external things that posed a potential threat to the body. The skin interface thus became the primary danger zone of possible penetration and infection.’ Underlining the momentousness of this change, both medically and more existentially, via the concept of individual autonomy, she adds that our ‘collective body image has changed only during the last two centuries to that of a closed, demarcated individual body whose final boundary is the skin’.⁶

The satirical writings of Scottish surgeon-turned-novelist Tobias Smollett illustrate a brackish tension between the therapeutic possibilities of fresh water on skin and salty physical and moral dangers. Smollett was a literary contemporary and rival of Laurence Sterne, who caricatured him in Tristram Shandy as the jaundiced Smelfungus. Smollett’s death in 1771 happened to coincide with medicine’s shift away from seeing the body as an extension of nature, subject to the natural and supernatural forces that governed a person’s humours. From the time of Hippocrates and Galen, internal imbalances and fluxes in the four ‘humours’ – the cardinal fluids of blood, phlegm, black bile and yellow bile – were understood to cause disease both on the inside and the outside of the body, whether pneumonia, dysentery, tumours, haemorrhoids, boils and so on. The humours also informed a person’s character: choleric, phlegmatic, sanguine or melancholic.⁷ Now, in a great leap forward, medicine began to identify the cause of sickness, first in airborne miasmas and later in germs, as something that could work on the body from the outside in.⁸ The establishment of the first Chair of Public Hygiene, within the Faculty of Medicine in Paris in 1793, neatly symbolises this shift, though it seems relevant to note that by the turn of the twentieth century, only 3 per cent of Parisian apartments had a bathroom.⁹ During the years between the French Revolution and the Fin de Siècle, the word ‘sanitary’ made its way into most European languages and transformed the infrastructure of its cities.

Smollett’s witty writings about taking the waters, or not, are a snapshot of his professional uncertainty about cutaneous absorption. Because he did not understand pathogens as we do, and believed that good health depended on an internal balance of humoural fluids, from our perspective, Dr Smollett – who would have been described as ‘choleric’ in temperament – seems entertaining but ignorant. His brilliant powers of observation, however, and his innate common sense trump his unsound medical knowledge.¹⁰

A sea-bathing enthusiast himself, Smollett wrote a famous medical paper in 1752 called An Essay on the External Use of Water, with the noble aim of purifying the mineral waters in the English resort town of Bath. Spa therapy at the time was more concerned with internal than external cleanliness: bathers drank the purgative mineral waters. Improvements at Bath were evidently slow, because twenty years later, in his 1771 novel The Expedition of Humphry Clinker, which takes place in the watery settings of spa towns and seaside resorts, Smollett has his gouty, hypochondriacal character Matthew Bramble write a letter to his physician. Bramble is ‘done with the waters’, and is now as afraid of drinking contaminated water as bathing in it:

Two days ago, I went into the King’s Bath, by the advice of our friend Ch——, in order to clear the strainer of the skin, for the benefit of a free perspiration; and the first object that saluted my eye was a child full of scrofulous ulcers carried in the arms of one of the guides under the very noses of the bathers. I was so shocked at the sight that I retired immediately with indignation and disgust. Suppose the matter of those ulcers, floating on the water, comes in contact with my skin when the pores are all open, I would ask you what must be the consequence? Good heaven, the very thought makes my blood run cold! We know not what sores may be running into the water while we are bathing, and what sort of matter we may thus imbibe; the king’s evil, the scurvy, the cancer, and the pox; and, no doubt, the heat will render the virus the more volatile and penetrating.¹¹

Smollett’s description of bathing is enough to make one reach for hand sanitiser, resolve to stop drinking tap water and vow never again to swim in public baths, no matter how chlorinated.

Two hundred and fifty years later, in 2020, a young American doctor and journalist named James Hamblin published a book called Clean, with a killer first line: ‘Five years ago, I stopped showering.’ As readers wrinkle their noses, Hamblin reassures them that he means showering in the traditional sense. My definition of ‘traditional showering’ would be soaping up under a flow of water adjusted to a perfect temperature, letting the body relax under gentle jets and setting the mind to wander. Music – performed a cappella or recorded – is optional. Showering this way is a luxury unique in human history and sets me apart from much of the world, where water is a hard-to-get necessity, not an indulgence.

Hamblin gets his hair wet occasionally, he says, but doesn’t use soap, deodorants, moisturiser or exfoliants so as not to disrupt his skin’s microbiome. He mentions his girlfriend a few times throughout the book; I can’t have been the only reader who wondered about a non-washing policy’s impact on interpersonal relationships. (According to a personal announcement in the New York Times, they are now married.) Hamblin looks more like Doogie Howser MD than the Unabomber and is self-aware enough to acknowledge that Whiteness and maleness make his regimen, or lack thereof, more acceptable for him than it might be for others.

Who can say if it was a boon or a misfortune to publish Clean in the middle of a global pandemic? Paranoid about viral contamination, we masked up, socially distanced and compulsively washed our hands with soap and water, or hand sanitiser. Hamblin, who swears he never gave up proper handwashing, also finds himself, in the process of writing his book, to be a historian of soap. (This makes him a historian of marketing too, and, for that matter, capitalism.) His journalistic ethos pushes him to frame the book as a news alert: ‘I came to believe that we are at the beginning of a dramatic shift in the basic conception of what it means to be clean.’¹² Just because he’s not bathing doesn’t mean neither are the rest of us, but his book is less fanatical and more persuasive than one might expect. While I was reading it, for example, my daily showers became my daily shower.

Clean is very much a book for our times. Its stated purpose is to get readers to consider what people in the world around them are doing to their skin, and what they are doing to their own. The skin’s microbiome, which Hamblin says is an ‘obsession’ of his, is central to this consideration.¹³ The notion of the gut microbiome is now so popularised that our minds jump to ‘good bacteria’ and ‘probiotics’ whenever we hear it mentioned. Cultured yoghurt, fermented kimchi, sourdough bread, miso and sauerkraut are not new, but many more people are entering this club of promised wellness, glass of kombucha in hand. Anyone who has eaten something and then broken out in hives (scientific name urticaria) will understand there is a relationship between our gut and our skin. But we have a complex epidermal ecosystem as well, and we’re not talking about scabies or lice.

Monty Lyman is in some ways the young English doctor counterpart to the American Hamblin, though he told me that while he is not a complete soap-dodger, he tries not to over-wash. Lyman writes evocatively in his book, ‘At first glance, our skin looks like a bare, inhospitable landscape. It’s clear, however, that our body is covered in habitats filled with wildlife worthy of a nature documentary.’¹⁴ If learning there are more non-human microbial cells on human bodies than there are human cells makes you pump frantically on your bottle of antibacterial soap, stop right there. We need these microorganisms (known as commensals, because they neither hurt nor benefit each other) – skin cells, immune cells and bacteria – to commune and remain in balance on our skin. They were around before we were and have evolved to defend their dwelling place, which is us. You and your microbes – fungi, bacteria, protozoa, archaea, viruses – are mutually dependent. You are part of them, and they are part of you. If it’s any consolation, there is evidence that the people you live with will come to share your microbiome, or vice versa, giving a new definition of couples that share everything.

Certain kinds of bacteria fight invading pathogens, assist in wound healing, suppress inflammation and inform the immune system. Anyone who lives with sporty teenagers will not be surprised to learn that feet have their own distinct bacterial ecosystem, with notable fungal diversity.¹⁵ You need a microscope to see all these living forms, except for – take a deep breath – the mites (Demodex) on your face, which, according to Hamblin, can be seen with a magnifying glass. (There is evidence that should levels of Demodex on the face get out of kilter, one possible outcome is rosacea.¹⁶) The revelation of our thriving skin microbiome – probably more than ten billion microbial cells on each of us – is a recent one, only made possible by DNA technology.¹⁷ Recognising the existence of the skin microbiome takes away some of the generic assumptions of ‘germ theory’, the idea that we must shun microbes to avoid disease. But distinguishing friends from foes is not always easy.

Although James Hamblin’s book was published during the pandemic, he researched and wrote it beforehand. So, he got to visit the trailblazers, prodigies and rising stars of the skin microbiome field in their labs and on their campuses, likely shaking their hands in the process. One luminary he met was Julie Segre PhD, who in 2012 became the first person to map the skin microbiome. Segre works in Bethesda, Maryland, at the National Human Genome Research Institute within the US National Institutes of Health (NIH). She is a leader of the Human Microbiome Project, where part of her job is to promote the concept of humans as ecological landscapes. Interestingly, this nods to earlier conceptions of the body as not separate from the external world because microorganisms make us biologically diverse.

Segre calls the skin and gut biomes our ‘second genome’; we have one genome made of human cells, and another made of non-human microorganisms. She suggests we should consider the microbiome as the twelfth system of the human body, one that unlike, say, the digestive, skeletal or muscular systems, we don’t know nearly enough about. Hamblin points out that this vast research project requires – and deserves – significant public money, separate from commercial interests. Segre says that understanding the microbiome will ‘Revolutionize what it means to be human and healthy’, and help us to ‘Fight our bacterial foes and cultivate our bacterial friends’.

She spoke these words during an hour I managed to spend in the company of NIH summer interns, watching online a lecture she gave in 2019. Her presentation was called ‘Human Microbiome Project – A personal and professional journey through kingdoms (bacteria, fungi, viruses) and genomes’.¹⁸ When Segre, wearing black and white, her hair pulled back in a chignon, talked about her background in mathematics and told students to take classes in computer science and statistics, I was reminded of Pablo Fernández-Peñas’s comment about melanoma and maths, and the need for translational research – where biology talks to medicine talks to computer science talks to dermatology talks to immunology, and so on. Translational research is tough given that, as Segre said in reflective mode at the end of the lecture, ‘Science is not set up for people to work in teams.’ So, I especially loved the way she interspersed photos of colleagues and collaborators through her talk, her final slide being a photo of her lab group’s annual hike. In her work, partnering with physicians is crucial, not least as she wants genomic questions to be answered in clinical – particularly dermatological – contexts so that patients benefit.

Segre did postdoctoral work in genomics and skin biology. Pondering the way her own brain works, she says, ‘I knew that I liked to be in on the beginnings of projects because then I can organise them and develop these large, high-quality data sets.’ During her lecture she uttered a phrase that anyone who remembers The Six Million Dollar Man will relish: ‘We have the technology.’ Referring to one machine she and her colleagues use as ‘a beast’, Segre says that the past ten years have seen ‘an amazing alteration in instruments that are available for doing sequencing’. But her skill with designing data sets is crucial, because an ocean of information is useless if you can’t extract meaning from it. Now, using a technique known as shotgun genomics, researchers break a genome from a skin swab into fragments – rather than growing it in lab cultures – sequence it to identify its components, remove the human DNA and, using a computer program, reassemble the microbes. This process can identify not only bacterial species, but bacterial strains. ‘What stands out here,’ says Segre, ‘is that the bacterial community is not specific to the individual. The biggest difference is the body site.’ In other words, which bacteria, and how many, live where.

Mapping the skin microbiome in effect maps dermatological trouble spots on the body, which, she says, are mainly in the same places from person to person: itchy eczema on elbows and knees, tenacious fungal nail infections and so on. Everyone’s skin, regardless of how they might self-categorise when buying skincare products, has oily, moist and dry terrains. So, Segre developed, as she puts it, ‘A topographic landscape that synced with what we knew about dermatological diseases’. It looks, as Hamblin writes, ‘like a map of chakras or acupuncture meridians’.¹⁹ We have bacteria all over us, often at the lipid-rich hair follicles, oases on the skin for microbes.

Bacteria can’t be easily divided into heroes and villains, because in certain situations benign bacteria can go bad. We feel anxious when we hear any permutation of the word ‘staph’, because we know about the problem of antibiotic-resistant golden staph infections (also known as MRSA) in hospitals. Staphylococcus aureus, the scientific name for golden staph, is harmless on unbroken skin but at the site of a severe eczema flare it can cause infection. Other Staphylococcus bacteria seem like good guys. Staphylococcus epidermidis secretes antimicrobial chemicals, can protect junctions between the skin-strengthening keratinocytes, and connects with T cells when a baby is born, training their immune system. Cutibacterium acnes would seem on the face of it to be an obvious cause of acne; get rid of that and perhaps we could say goodbye to spots. But while its link to acne is acknowledged, its specific contribution is uncertain and dependent on complex interactions with the skin’s immune system. One study called C. acnes ‘Janus-faced’: both beneficial and detrimental.²⁰ One problem with taking antibiotics for acne, and everything else, is that they can knock all the bacteria out, including the commensals.

‘Maintaining sterility is costly,’ says Segre. Shunning every ‘antibacterial’ product – liquid soaps, disposable wipes, detergents, kitchen and bathroom cleaning sprays – will save more than money. Plain old soap will usually do the job, as anyone who saw a ‘How does soap work against coronavirus?’ public health video will know. Soap molecules destroy bacteria and viruses, acting like a ‘crowbar’, as well as stopping microorganisms (and grime) from sticking to the skin.²¹ The biggest challenge to our microbiomes, skin, gut and others, is overuse of antibiotics. It is not grandiose to proclaim antibiotic-resistant superbugs an existential threat, one comparable with climate change and exacerbated by it.²²

Hamblin asks Segre, as he does everyone, about her bathing habits. Her response is excellent and has been quoted all over the place. (She asked me to remind readers that she was speaking before COVID-19 and the unique public health hand-washing response the virus necessitated.) ‘I don’t understand exactly why it is that people have such a different sense of the microbes that live in their gut than they do about the microbes that live on their skin,’ she says. ‘Everyone wants to eat Activia yogurt and colonize their guts with bacteria, and then they want to use Purell on their skin.’²³

Microorganisms don’t sit on the surface of our skin clinging on for dear life while their host showers (although excessive soapy showering, as we’ve seen, is a challenge). They don’t get swept up with the million or so dead skin cells we lose every day. As Lyman writes, ‘they are tiny organisms, thousandths of a millimetre long, hiding in the canyons and crevices of our surface’.²⁴ The problem is that the products we use can alter the ideal environment for friendly bacteria. So, how can we cultivate good bacteria on our skin? Skin microbiome ‘transplants’ for diseases such as eczema could become possible in time, in the way that faecal transplants are becoming more common for issues relating to gut microbiota, but topical probiotics are available right now. Do they work?²⁵

Hamblin visits a Natural Products Expo, ‘Where,’ he says, ‘the term “probiotic” seems to be treated as a synonym of “good for you”.’ Even though it’s hard to keep probiotics ‘live’, and the notion of prebiotics is encouraging but not tested, the fact that there is so much money to be made means that hordes of researchers, manufacturers, investors and marketers are on the case. An informative video I watched about the skin microbiome was produced by the scientific journal Nature but sponsored by Unilever. Acknowledgement of this commercial support was clearly displayed, and the journal’s editorial independence asserted, but Unilever is perhaps the most prominent global corporation in all the histories of soap I inadvertently read while researching the skin microbiome. This is a perfect example of what Hamblin describes in his book as a ‘pivot’, where manufacturers hopping on the probiotic trend must convince people that cleanliness is overrated, so don’t use soap, but buy this new product to restore bacteria to your skin instead.

Confident I couldn’t be sucked into this probiotic soap malarkey, I examined the bottle sitting next to my bathroom sink. Sheepishness replaced smugness when I read the label – ‘Probiotic Cleaning Tonic, with 13 probiotic cultures and essential oils.’ Resistance is not futile, but consumers need to have their wits about them. When I first googled ‘skin microbiome’ the top hit was not Nature, or Julie Segre, but wellness headquarters Goop. Once you start looking, you’ll see probiotic everything, everywhere. Piled up below the produce tables in the fruit and vegetable market, I spotted sacks of something called ‘Soilbiotic – probiotics for your soil’. So, there is no question that our lifestyle contributes to the drama playing out on our skin, but what if it is coming from within, as well as from what we’re rubbing into it?

The film Safe, directed by Todd Haynes and starring Julianne Moore, was released in 1995 but was a kind of period piece even then, given the film is set in a Reaganite 1987. Payphones, and suitcases that must be carried because they don’t have wheels, leap from the screen like museum artefacts. The film’s themes of immunity, contamination and therapeutic culture, however – what we now call ‘wellness’ – are astoundingly prescient. The California sunshine of the San Fernando Valley in no way ameliorates Safe’s ominous tone. Nor does the opulence and privilege of the main character’s life, or the teal, lilac and salmon-coloured puffed sleeves and aerobics lycra she and her friends wear. Never have pastels seemed so malevolent.

Carol White is somehow a blank, even though she’s the protagonist. An attractive but inarticulate woman so bland she seems amorphous, Moore plays her with a restraint that makes this one of the actor’s best performances. Pale and slender, Carol is like a ghost in her own life. She is nearly always filmed in wide angle: in her car, surrounded by Los Angeles traffic; calling out to her Mexican maid as she walks through her vast, pristine house; at a baby shower, surrounded by pastel decor, silver balloons and blue-frosted cake. Carol eats carefully, at one point going on an all-fruit diet with a friend, ‘to naturally cleanse the body of all toxins’. A self-confessed ‘milkaholic’, she doesn’t drink alcohol or coffee. But she starts to feel unwell. A sneeze is the first sound she makes in the film. Before long she is tired and headachy, her sinuses flare, she has a rash. Her symptoms get worse, but tests find nothing. Does the threat come from outside or within?

Safe might be an unsentimental take on the disease movie; the question of whether Carol will overcome her mysterious affliction and inspire us all is hardly asked. If it’s satirical, Safe offers few laughs. Carol’s profound alienation from the world in which she lives, and the bleak emptiness of that world, pushes it towards science fiction or horror. In an interview at the Film Society of New York’s Lincoln Center, Todd Haynes said, ‘I wanted it to feel like all the air in Safe was recycled air, like you were in an airport and you were on one of those conveyer walkways and everything was just carpet that would go from floor to ceiling . . . The sense of the natural being completely removed from human existence.’²⁶

Towards the start of the film, Carol – in makeup and wearing bright clothes – is in her manicured garden tending her yellow roses. By the end, she is a resident – temporary, but who knows – at Wrenwood. This New-Age community in the New Mexico desert is awash with the cultish language of self-help. Wearing unbleached cotton and no makeup, and dragging an oxygen tank behind her, Carol enters a porcelain-lined white igloo, separate from both Wrenwood and the wider world. Her safe house. Her total isolation is chilling enough, but the viewer’s blood runs colder in the final scene. She stands in her spartan room looking into the mirror, an unexplained sore on her forehead, mouthing the words ‘I love you’. On paper it may seem that she’s rebuilding her esteem and excavating her true self. But the grim tone negates any sense of a happy ending. The scene layers internal alienation upon external alienation, sham interiority engaged in mutually assured destruction with a soulless exterior.

Midway through the film, after an aerobics class, one of Carol’s friends notices that she doesn’t sweat. I had seen this as another way Carol isn’t present in the world, but my fresh knowledge about the skin microbiome meant that when I re-watched the film, I saw this observation as yet another way it is ahead of its time. She diagnoses herself with ‘environmental illness’ after seeing a flyer on the gym’s noticeboard. It poses a set of bullet-point questions: ‘Do you smell FUMES? Are you allergic to the 20th century? Do you have trouble breathing? Is your drinking water pure? Do you suffer from skin irritations? Are you always tired?’ Carol’s answer to all these is, of course, yes. We have seen her nose bleed after a manicure and perm at the salon. Emerging from the shower at home, her husband sprays on aerosol deodorant, cologne and hair lacquer before embracing her. She promptly vomits. In a scene I have recalled every time I have picked up dry cleaning since I first saw Safe in 1995, she has an anaphylactic fit, convulsing on the floor, surrounded by plastic-sheathed clothes on hangers. Inside the ambulance taking her away, an oxygen mask covers her face. She is bleeding, but how, from what? The sense of horror is acute.

Carol identifies with the community of people around her who are sick, like she is. The message they get from Wrenwood’s ‘guru’ is that sickness is the individual’s fault. They made themselves sick. Bombastic, selfish and – we assume from his big house at the top of the hill – rich, this man describes himself as ‘a chemically sensitive person with AIDS’. Sermonising, he says he’s stopped reading the papers, stopped engaging with the fatalistic, negative media, all that gloom and doom. ‘Because if I believe the world is that destructive, I’m afraid my immune system will believe it too. I can’t afford to believe it. Neither can you.’

Haynes has said he made the film as a metaphor for AIDS and the culture of blame that surrounded it. Watching Safe in the time of another viral plague, COVID-19, I thought that the film’s allegorical force might easily propel citizens into their own sealed, decontaminated igloos. Its general sense of peril, relentless and invisible, makes it terrifying. And a masterpiece.²⁷ It could be about climate change – what carbon in the atmosphere and acidity in the oceans is doing to the environment, and what it’s doing to us. We want the planet to be immune, to somehow fight back and protect itself, even as we destroy it. But closer to the film’s original meaning, we want to boost our personal immunity just as much, maybe more.

Thinking of everything around you as an enemy of your immune system is exhausting, as is trying to comprehend why your immune system would betray you by attacking itself. External environmental factors can be the trigger for autoimmune diseases such as psoriasis, eczema, lupus and Crohn’s disease, but the individual’s unique internal biology is the cause.²⁸ The implications of this older conception of medicine, humours and the chaotic sense of things being out of our control, were at the front of my mind when I talked to Dr Preeti Joshi. She is a specialist in paediatric allergies and immunology, and co-chair of Australia’s National Allergy Strategy Steering Committee. She works in private practice and in one of Australia’s largest children’s hospitals.

I remember calling Joshi years ago from Bali when my daughter, Bella, was sick. She was extraordinarily calm as she talked me down from unwarranted panic. This poise is surely an asset when she is treating allergy patients who are potentially on the verge of anaphylactic shock. I knew that her children, the same age as my own, had conditions that related somehow to her profession. Indeed, she confirmed one has coeliac disease, the other has a severe food allergy and they both have eczema. But she explains that her choice of specialisation preceded her children, one of those strange coincidences life throws at us.

Joshi tells me about what she sees at the coalface of allergies and immunity, particularly as they pertain to skin, and what has changed. ‘We’re talking about dysregulated immune systems that are responding in an overreactive way to something that should be harmless. Eczema – very bad eczema – is the top skin condition I manage, from newborn babies to eighteen-year-olds. I see kids who are on the atopic march.’ This refers to the common array of conditions, often chronic, where children develop eczema, food allergies, asthma and allergic rhinitis (or hay fever). She says that while the rate of asthma has stabilised, she is seeing an increase in allergies and autoimmune conditions. ‘When people look at the data about this, they see that by 2012 or so we had a doubling in the rate of food allergy from the previous ten years. This can’t be due to a change in genetics. A Melbourne study from around then found that one in ten infants is born with a true food allergy. That’s astounding. This is not a parent who says, “Oh, my child has a food allergy.” It’s specific allergy testing where they’re challenging that baby to a particular food and the baby reacts.’ Among the most common of many possible reactions are hives, redness and itching.

I ask a question too complex for Joshi, or probably anyone, to answer. Why are allergies and immune and inflammatory conditions getting worse? The microbial biodiversity argument is part of the reason, she says, but the causes are intricate and complex. ‘Nobody has a definitive answer. I wonder whether it is the genetic combination these kids have, combined with whatever microbiota they’re exposed to in the environment they’re born into. Plus or minus whatever plagues the mum. Because you’ve got all those factors from the mother’s gut microbiota – and maybe her skin as well. Overall, it’s just not gelling enough to protect these kids.’

We talk about the ‘hygiene hypothesis’, the idea that just as microbes can cause disease, a lack of microbes in sterile environments might also cause disease. (This is what Clean is all about, and what Carol in Safe couldn’t countenance.) ‘It seems we’re not being exposed to endotoxins – the things that come from the bacteria in our environment – so perhaps the immune system is not being stimulated in the direction that it needs to be. It is reacting to things it should not react to. There’s certainly a lot of epidemiological evidence for this in genetically similar populations with different environments. I think there’s something to it.’ When I ask if we should be making children play in the dirt, she responds with a valid counter-question: ‘What kind of dirt are we talking about? It’s more than that. Because, say if you’re not eating vegetables that are grown in the ground near your place, and everything you eat is washed clean and sanitised, you’re not getting those good bacteria into your gut either.’

One known fact about eczema, as we’ve seen, is that the skin’s barrier breaks down because of deficiencies in the filaggrin protein. Joshi says, ‘That is certainly part of the story, but remember the concept of the skin as a barrier that helps keeps moisture in and irritants out. I wonder, if you don’t have that shield of the microbiome, do those receptors get more active as well? So, if you’ve got chemicals that you’re spraying on surfaces all around you, or we’re soaping our infants with baby wash, how much are we breaking down a barrier that’s already a bit fragile? By the time you’ve got eczema it’s probably too late.’

Shelves groaning with baby hygiene products are not the sole cause of allergies and eczema, but Joshi tells me she always says to parents, ‘Don’t put anything on your baby’s skin. If you must put anything at all, use a fragrance-free moisturiser, not a “natural” moisturiser. Just a sorbolene cream. That’s it. Don’t break down the skin barrier more with chemicals.’ Before our conversation I had never thought about how often food is used as an ingredient in products branded ‘natural’. Joshi tells me that moisturisers containing oats or coconut, for example, can sensitise babies and toddlers. ‘We’re not supposed to be slathering broken skin in food. When you’re applying it to your skin but not eating it, you can actually develop a food allergy.’ A better topical approach is to use whatever possible to reconstruct the barrier. As well as sorbolene, ceramides (lipid molecules found in the skin and in certain creams) can help in some cases.

Interestingly, Joshi says researchers have tried, unsuccessfully, to get funding for studies with titles such as ‘Don’t soap the baby’. She explains, ‘We’re up against a lot of commercial interests.’ I think of the products given away to new parents in maternity hospitals, including, previously, a brand of nappy wipe that had the preservative methylisothiazolinone (MI), which the American Contact Dermatitis Society named ‘Allergen of the Year’ in 2013. With the knowledge about the history of soap I ended up myself acquiring, I can only agree that the commercial interests are overwhelming.

Veering as I have between hype about biota, biologics, the miracle cure of doing nothing and so many stories of suffering caused by skin conditions, I ask Joshi if she’s optimistic about treatments and cures, not to mention prevalence. ‘I feel like we’re on the edge of a few answers. Things that are starting to be worked out make me feel a little more hopeful, particularly to do with our environment and ways to improve our inflammatory drive. Even kids going to preschool outside – there’s lots of research on that – makes me think we might be able to work out what we’re not getting right. Because we are getting more inflamed. And that’s worrying to me.’ She muses that much depends on society finding the energy, time and money to devote to this research, observing that at least the pandemic has given people a lot of thinking time.

And outdoors time. While chatting to a gardener, I found myself asking if he had skin conditions or allergies. His answer fascinated me. ‘No, there was a cow at my high school, so no one got anything.’ This echoes an argument James Hamblin makes in his book. He visits an Amish community in Indiana, where houses and farms are cheek-by-jowl and allergies are rare. These Amish have, he says, ‘by all credible accounts, abnormally good skin.’²⁹ We can’t all move from cities to old-style, non-mechanised farms where we grow our own food, off the grid. Nor would many of us want to. But we can champion parks. And spend time in them. Hamblin writes about Frederick Law Olmsted’s legacy of public parks, including Prospect Park near where Hamblin lives in Brooklyn. He calls them ‘living embodiments of public health’.³⁰

Patch-testing supremo Rosemary Nixon finished the talk that opened this chapter by reflecting on what makes a good physician. ‘To be a good doctor,’ she said, ‘you have to have your own life under control. I think that’s important when we look after patients, which is a great privilege.’ To achieve this, she encouraged getting into nature, not necessarily camping in rugged wilderness but being active in local parks and gardens. As it happens, she used my favourite Japanese word, shinrin-yoku. It means forest bathing. Put down your phone. Walk into the bush, a national park, woodland, forest, a garden, the wild. Lean against a tree, run your finger along its bark, scrunch a leaf in your hand. Lie down on the earth. Look up to the sky and breathe those trees in. Feel the life in them. Let them seep into your skin.