↑ Free Format Kindle Download [ An Epidemic of Absence: A New Way of Understanding Allergies and Autoimmune Diseases ] ⇷ Kindle Author Moises Velasquez Manoff ∬

↑ Free Format Kindle Download [ An Epidemic of Absence: A New Way of Understanding Allergies and Autoimmune Diseases ] ⇷ Kindle Author Moises Velasquez Manoff ∬ ↑ Free Format Kindle Download [ An Epidemic of Absence: A New Way of Understanding Allergies and Autoimmune Diseases ] ⇷ Kindle Author Moises Velasquez Manoff ∬ An Epidemic of Absence CHAPTER 1 Meet Your Parasites Mother, it is no gain, thy bondage of finery, if it keep one shut off from the healthful dust of the earth, if it rob one of the right of entrance to the great fair of common human life.1 Rabindranath Tagore,Bengali poet and Nobel laureate One chilly November morning, I head south from San Diego in a bottom tier rental car The standard journalistic paraphernaliaa digital recorder, camera, notepad, and pencilsaccompany me in the passenger seat, as well as directions to my meeting point the last exit before Mexico I also have a printout of my recent blood work, proof that Im not anemic, not infected with hepatitis or HIVthat Im healthy enough for the coming experiment As I drive, the radio announcer conducts a gruesome tally of the most recent violence in Tijuana, where Im headed two bodies hung from a bridge, a third decapitated, a fourth shot More than this terrible, ongoing brutality, however, parasites occupy my mindworms that migrate through flesh, burst into lungs, crawl down throats, and latch on to tender insides Any traveler might fret over acquiring such hangers on while abroad But Im heading to Mexico precisely to obtain not just one, but a colony Today in Tijuana Ill deliberately introduce the hookworm Necator americanusthe American murdererinto my body And for this dubious honor, Ill pay handsomelya onetime fee of 2,300 If I receive twenty of the microscopic larvae, thats 115 apiece for a parasite that, in the early decades of the twentieth century, was considered a scourge on the American south Some worriedwithout condescension, I should addthat hookworm was making southerners dim witted and lazy, that it was socially and economically retarding half the country And photos of poor, worm ridden country folk from the timefollowed by their robust health after dewormingclearly show the dire costs of necatoriasis, or hookworm disease jutting collarbones, dull eyes, and listless expressions on wan faces They appear as if consumed from the inside Hookworm has mostly disappeared from the U.S., the result of protracted eradication efforts in the early twentieth century But in the usually poor, tropical countries where its still endemic, it can cause anemia, stunt growth, halt menstruation, and even retard mental development in growing children Between 576 million and 740 million people carry the parasite And for all the aforementioned reasons, public health types consider worm infections a neglected tropical disease Helminths, as theyre called, are not as obviously fatal as malaria, say, but their constant drag on vitality is insidious The parasites keep children from learning in school They prevent parents from working Some argue that they contribute to the self reinforcing cycles of poor health and poverty that plague entire nations So why am I considering acquiring this terrible creature Scientists have two minds about parasites these days Some consider them evil incarnate, but others note that while the above mentioned horrors are sometimes true, the majority of humans infected with parasites todayupward of 1.2 billion people, or somewhere between one fifth and one sixth of humanityhost worms with few apparent symptoms This camp has begun to suspect that worms may, in fact, confer some benefits on their human hosts As early as the 1960s, by which time hookworm had been largely eradicated in the U.S., scientists puzzled over the lack of symptoms in some Well nourished persons often harbor helminths without apparent damage, remarked one physician in 1969.2 One may question the wisdom of treating such infections, especially with chemotherapeutic agents with toxic qualities Decades of plumbing the mechanisms that allow one creature to persist within another, a clear violation of the self versus nonself rules thought to govern immune functioning, has taught immunologists much not only about how wily worms really are, but also about how the human immune system actually works Parasites like hookworm were ubiquitous during our evolution Might our bodies anticipate their presence in some respects, require it even And might some of the curious ailments of modernity result partly from their absence That brings me to my motive A large and growing body of science indicates that parasites may prevent allergic and autoimmune diseases And Ive got both When I was eleven, my hair began falling out My grandmother first noticed it I was visiting my grandparents at their beach house that summer when, one afternoon, she called me over, examined the back of my head, and proclaimed that I had a nickel sized bald spot Then we all promptly forgot about it With the sand, waves, and sun beckoning, it just didnt seem that important But by the time school started a few months later, the bald patch had grown A dermatologist diagnosed alopecia areata, an autoimmune disorder My immune system, normally tasked with protecting against invaders, had inexplicably mistaken friend for foe, and attacked my hair follicles Scientists didnt know what, exactly, triggered alopecia, but stress was thought to play a role And at first glance, that made sense My parents were in the middle of a messy, drawn out divorce I was also beginning at a new junior high school that fall I had, it seemed, much to worry about I also had other, better known immune mediated problems I suffered from fairly severe asthma as a child, and food allergies to peanuts, sesame, and eggs Only the egg allergy eventually disappeared At least once yearly, usually during seasons of high pollen count, my wheezing became so severe that my lips and fingernails turned blue, and my parents had to rush me to the emergency room There, doctors misted me with bronchodilators, or, during severe attacks, pumped me full of immune suppressing steroids Aha said the dermatologist when he learned of these other conditions There was a correlation among allergies, asthma, and alopecia, he explained No one was sure why or what it meant, but having an allergic disease like asthma increased ones chances of developing alopecia Years later, I would learn that the co occurrence of these two disorders was likely evidence of a single, root malfunction But at age eleven, I accepted on faith that where one problem arose, so, probably, would others So what to do Given my age and the relatively small size of the bald spot, the doctor recommended watching and waiting Alopecia usually corrected itself in time, he said So we waited In a month, another bald spot appeared, on the right side of my head Then one on the left Seemingly overnight, a large one opened up just above the middle of my forehead As hairless patches appeared, the pace at which new ones emerged accelerated Every morning, my mother combed and gelled my hair into place to hide the growing expanse of denuded skin but soon, concealing my bare scalp became nearly impossible The spots began to converge I was going bald We returned to the dermatologist This time, he had a less upbeat assessment The the disease progressed, he noted, the less likely recovery The odds worked like this Only 1 to 2 percent of the population got alopecia areata at all, a bald spot or two that, after a time, usually filled in again.3 But for a significant minority, maybe 7 percent of those with alopecia areata, the hair loss became chronic Some progressed to alopecia totalis, total loss of hair on the head At that point, the chances of a full recovery diminished substantially Whatever mistake the immune system had made, it became permanent And of this totalis subset, some went on to develop alopecia universalisloss of hair on the entire body For them, recovery was nearly impossible None of this sounded good, especially as I was speeding toward totalis andwho knows universalis after that Two treatment options existed, neither of which worked without fail immune suppression or irritation Steroids suppressed the immune response and, basically, called off the attack dogs, allowing hair to grow again Immune stimulation, on the other hand, worked in slightly mysterious ways Inflammation induced by an irritant distracted the immune system from less pressing projects, such as attacking hair follicles Irritation would earn my hair follicles a reprieve As neither approach was a sure bet, the dermatologist recommended that I try both I did, and neither workedalthough I developed an oozing blister where I applied the irritant My alopecia advanced until, by age sixteen, not a single hair remained on my body I had joined the elite ranks, somewhere around 0.1 percent of the population, of those with alopecia universalis I put on a hat, which Id wear or less nonstop until my early twenties, and tried to get on with my adolescence Not until my thirties did I look into what scientists had discovered in the roughly twenty years since that first bald spot appeared on my head I wasnt too hopeful surely, I would have heard had a cure been developed As I contemplated having children, Id begun fretting about what lay hidden in my genes The first genome wide association study of alopecia, published in 2010, showed that the disorder, the most common autoimmune disease in the U.S., shared gene variants with several much worse autoimmune diseases, such as rheumatoid arthritis, type 1 diabetes, and celiac disease.4 Soon thereafter, my first child, a girl, arrived Now the results of my investigation had concrete applications If alopecia suggested a tendency toward immune malfunction, and if that tendency was modifiable, I wanted to know how to better play the cards I wanted to ensure that my progeny remained free of both allergic and autoimmune disease I was right about one thing Treatments for alopecia hadnt advanced much since my childhood They still consisted mainly of irritants and immune suppressants, and as neither approach corrected the underlying malfunction, both would require indefinite use Prolonged exposure raised a host of secondary concerns Repeated steroid shots, for example, were not only exceptionally painful, they thinned and discolored the skin Irritants induced swelling, redness, and skin flaking One powerful immune suppressant called cyclosporine increased the risk of skin cancer No thanks However, the patterns of immune mediated disease in general caught my attention The incidence of both autoimmune and allergic diseases had recently increased, and to the degree that scientific literature conveys feeling, in this case it evinced alarm Scientists threw around the word epidemic to describe the rising prevalence of asthma especially, a descriptor usually reserved for infectious diseases, like the prayer inducing, body wasting, dead in a day cholera epidemics that terrified the world during the nineteenth century Generally speaking, however, there was no asthma bacterium, no autoimmune virus No new plagues were driving this particular pandemic Instead, we seemed newly vulnerable to immune dysfunction If I possessed glasses that afforded me the power to see otherwise non apparent allergic and autoimmune diseases, Id be struck by the sheer abundance of people with these problems Walking down Broadway in New York City, for instance, one of every ten children passing by would have asthma one in six would have an itchy rash and sometimes blisterseczema.5 One of every five passersby would have hay fever If I could see allergic antibodies directlyimmunoglobulin EId note that half the crowd around me was sensitized to dust mites, tree pollen, and peanuts, among other basically harmless proteins Id see pockets full of inhalers, and bags stuffed with allergy medicines In the satchels of the most severely afflicted, Id see pills of powerful immune suppressants, such as prednisone Id even see a few soon to be corpses about 3,500 people die yearly from asthma attacks Americans spend perhaps 10 billion yearly on asthma related drugs and doctor visits Direct and indirect costs of asthma combined reach about 56 billion Id see these funds flowing from allergic and asthmatic wallets to doctors and drug companies And Id observe money not flowing from days missed at work, diminished overall productivity, and opportunities lost over a lifetime If I took the same walk with glasses that allowed me to see autoimmune diseases, Id note that one in twenty passersby had one of eighty of these often debilitating conditions.6 One of every 250 peopleit would take about a minute standing in a place like Times Square for such a person to pass bywould suffer from debilitating pain in his or her intestines, whats called inflammatory bowel disease.7 Id see scarring and constriction And in the most severe cases, Id observe removed lengths of intestine, colostomies surgically created exits for intestinal contents , and colostomy bags containers for the effluence hidden under clothes Of every thousand passersby, Id note one struggling to move legs or arms These people have multiple sclerosis, a progressive autoimmune disease of the central nervous system Their vision might blur when they read signs Their legs might fail to cooperate when crossing the street The worst cases, of course, wouldnt be out at all Theyd remain at home, perhaps in electric wheelchairs, maybe bedridden Id note glucose monitors on one of every three hundred children frolicking in Central Parks playgrounds, children afflicted with autoimmune diabetes, which is usually childhood onset.8 Their skin would bear needle marks from the daily insulin injections required to avoid coma and death If my glasses came with headphones, Id hear a cacophony of worry and desperation asthmatic teenagers wondering if theyll be able to join friends in a game of baseball severe cases focused on walking slowly, so as not to lose breath eczematics reminding themselves ceaselessly not to scratch, or if theyve already scratched, berating themselves for the raw mess left behind Those with inflammatory bowel disease might be preoccupied with the pain, sometimes dull, sometimes sharp, that has characterized life since diagnosis If its not racking cramps on their minds, theyll likely be strategizing around bowel movements, which arrive all too frequently and with a painful urgency, and which sometimes contain blood Those with MS might be wondering How much longer before I cant walk And everyone will regularly ask Why cant doctors fix this Where did this come from Why me The National Institutes of Health estimate that between 14.7 and 23.5 million Americans have an autoimmune disease, or 5 to 8 percent of the population The American Autoimmune Related Diseases Association puts the number at than double that50 million Americans In the U.S., autoimmune disease ranks among the top ten killers of women And that speaks to an omission I made for simplicitys sake in the above scenario Roughly three quarters of those afflicted with autoimmune disease are female When I had my autoimmune glasses on, in other words, Id be seeing mostly women Anthony Fauci, director of the National Institutes of Allergy and Infectious Diseases, once estimated that the direct and indirect costs of autoimmune diseases reached a staggering 100 billion yearly By comparison, we spend 57 billion on cancer and 200 billion on cardiovascular disease That may seem high, but bear in mind that autoimmune diseases, which are chronic in nature, generally strike in the prime of life, and require decades of costly symptom management These statistics apply to the richest countries in the early twenty first century But immune mediated diseases werent always this prevalent Early hints of immune dysfunction during the late nineteenth century notwithstanding, the allergy and asthma epidemics gained steam during the 1960s, accelerated through the 1980s, and then plateaued by the early 2000s In that period, depending on the study and the population, youll find somewhere between a doubling and a tripling of asthma and allergies in the developed world Some autoimmune diseases show even dramatic increases during the late twentieth century A 2009 study found that the prevalence of undiagnosed celiac disease, a type of inflammatory bowel disease incited by proteins in grains, had increased than fourfold since the mid twentieth century.9 The incidence of multiple sclerosis has nearly tripled And for some of these diseases, theres no end in sight The incidence of type 1 diabetes, which than tripled during the late twentieth century, is estimated to double again by 2020 What has happened In 2002, the French scientist Jean Franois Bach published a seminal paper for anyone asking that question.10 The study, which appeared in the New England Journal of Medicine, had two graphs side by side, one showing the gradual decline since 1950 of once common infectious diseaseshepatitis A, measles, mumps, and tuberculosisnext to another showing, over the same period, an increase of autoimmune and allergic disease in the developed world Nearly everyone contracted mumps and measles in 1950 By 1980, almost no one did Vaccines had almost eliminated both viruses In an even shorter periodsince 1970new cases of hepatitis A infection fell to one fifth their former level And all the while, new cases of asthma, multiple sclerosis, and Crohns disease doubled, tripled, and quadrupled, respectively Source Bach, New England Journal of Medicine 2002 The relationship that Bach so clearly demonstrates, that as infections decline over time, immune dysfunction increases, is evident between contemporaneous regions and populations The incidence of allergic disease varies by a factor of 20 between the most allergic countries and the least Vanishingly few children in Albania, for example, have allergy, but one quarter of Australian children do.11 The incidence of type 1 diabetes varies even markedly350 fold between the most afflicted country, Finland, and the least, China.12 Are some ethnicities vulnerable to these disorders than others Maybe However, when migrants move from low risk to high risk countries, the children born to them in their adopted homelands almost invariably suffer from immune mediated diseases at rates equal to, and sometimes higher than, the local population So, if not genetics, what explains the great disparity Epidemiologists used to assert that, generally speaking, these disorders increased as you moved from the equator toward the poles In sub Saharan Africa they were quite rare In the U.K., they were all too common And that seemed irrefutably true even thirty years ago But evidence of a recent surge of asthma in countries like Brazil and Peruand urban centers in the developing world everywherehas undermined this once safely made generalization Nowadays, youre likely to hear that allergic and autoimmune diseases correlate with gross domestic product And for now, thats holding true The richer the country you call homeor in some cases, the higher your social class within a countrythe likely you are to have asthma, inflammatory bowel disease, and multiple sclerosis Critics discount these sweeping statistics for their reliance on questionnaires Surveys are inevitably vulnerable to recall and cultural biases, they point out But smaller studies that use objective measures such as wheeze and skin prick tests, or testing for autoimmune antibodies, have repeatedly revealed the same basic pattern Immune mediated disorders arise in direct proportion to affluence and Westernization The that ones surroundings resemble the environment in which we evolvedrife with infections and lots of what one scientist calls animals, faeces and mudthe lower the prevalence of these diseases.13 BETWEEN THE STONE AGE AND THE NEOLITHIC, NO ASTHMA In preparing for my Mexico trip, I often pondered another Id taken, to a place where asthma didnt exist the Bolivian The anthropologists Michael Gurven from the University of California, Santa Barbara, and Hillard Kaplan from the University of New Mexico, Albuquerque, study a horticulturalist people living on the western edge of the basin Theyre called the Tsimane, and they subsist, for the most part, directly off the jungle They hunt monkeys, tapirs, and other animals with bows and arrows They happily use rifles, which some possess but because they dont regularly participate in a cash economy, they often lack shells They fish with weirs, poison plants, and special arrows And although they have plenty of contact with twenty first century Bolivians, their lifestyle is as close to Stone Age living as one can reasonably expect to find these days Thats why Gurven and Kaplan are here I caught up with Gurven, smiling, scruffy, and wearing a Phillies cap, at his clinic on the outskirts of a bustling, dusty town in the Bolivian lowlands called San Borja Horses grazed in a nearby soccer field Handsome, sand colored cows wandered about The occasional sow trotted by Gurven belongs to a school of anthropology called human behavioral ecology The tools come from biology the novelty is their application in anthropology To hear him tell it, behavioral ecology emerged in reaction not to the cultural anthropology of the early and mid twentieth centuryMargaret Mead and her study Coming of Age in Samoa, for examplebut to the period of anxious self examination that followed Was the very notion of studying humans imperialistic and exploitative Could an outsider truly understand the other, or was she doomed to endlessly project herself on her study subjects Behavioral ecology, as applied to the study of people, as Gurven and his students explain to me around campfires during the coming nights, originates in a certain weariness, not necessarily with this self questioning, justified as it may be, but with the retreat from even trying to comprehend those who inhabit different worlds Yes, we inevitably project, but people who continue to live as we all once lived can teach us many things, and there are objective ways to measure these things Whats , anyone interested in these lessons had better move fast Whatever hunter gatherers and horticulturalists remain in the world wont be at it for much longer Among the Tsimane, Gurven first studied human reciprocity and altruism, why people share in a world of limited resources He asked questions like How does a sick person get help in a world without health insurance And why do people help the ailing when it costs them precious time and energy He also explored how humans age under the or less constant onslaught of infections Even here, people live decades beyond their capacity to bear children According to the most severe interpretations of Darwinian theory, that just shouldnt happen But for Homo sapiens, it does What are those extra decades for As part of his arrangement with the tribe, Gurven gives the Tsimane free medical care He trucks them to his clinic from the remote villages along the tributaries of the Maniqui River A doctor examines them Technicians take stool, urine, and blood samples In one darkened room, an ultrasound machine peers at their hearts and arteries Well revisit the specifics of Gurvens findings later, but, almost incidentally, hes found that the immune system of a horticulturalist living in the works differently than your average Londoners or New Yorkers Over the past decade, Gurvens clinic has examined than 12,000 people, almost the entire Tsimane population In the 37,000 examinations conducted by his staff theyve seen many patients multiple times , no doctor has logged a single case of asthma.14 If rates approximated those in the U.S and the U.K., youd expect at least 1,000 asthmatics As for autoimmune disease, hes seen fifteen casesincluding eleven of vitiligo, a condition in which the immune system turns on pigment producing cells in the skin, one of lupus, and one of rheumatoid arthritis If autoimmune disease occurred with the same frequency here as in the developed world, he should have seen roughly six hundred cases In Tsimana, in other words, the prevalence of autoimmune disease is one fortieth what it is in New York City What he does see are plenty of infections, which cause half of all deaths among the Tsimane Accidents and violence contribute an additional 14 percent And parasites are so universal as to be nearly unremarkable Theres lots of giardia and amoebiasis A few have tuberculosis Fewer still have a chronic flesh eating parasite called leishmaniasis And nearly everyone has hookworm He also sees plenty of the wear and tear that comes from an active life prolapsed uteruses, the result of having many children the average Tsimane woman has nine , and hernias from heavy lifting But the diseases of civilization, including cancers of the breast, prostate, ovary, colon, and testicle, are absent And so is cardiovascular disease Are the Tsimane special, genetically immune perhaps Others studying unacculturated Amerindians in the have explicitly noted the same absence of allergic disorders, and the suite of diseases so common in modernity.15 Maybe Amerindians as a group are genetically invulnerable to these diseases Perhaps, but not likely Scientists have made similar observations among peoples in Europe, Africa, and Asia The repeated observation is that people living in dirtier surroundings have less allergy and autoimmunity The reverse holds true as well Anyone seems able to develop asthma if exposed to the right conditions And these conditions prevail in places like New York City, London, and Sydney WHAT DOES A PLACE WITHOUT ASTHMA LOOK LIKE The day after I find Gurven, we drive an hour through cane fields and pasture to a red hued river We pile into a motorized dugout canoe, its sides shored up by planks The month is August, the Southern Hemisphere winter, and its chillier than one might anticipate for the jungle A wind called el surazothe southerlyblows off the vast pampas to the south Later Ill learn that this particular winter was so cold that fish and pink river dolphins washed up dead throughout ia After than an hour of motoring past snowy white egrets, the same species that steps gingerly through the marshland of New York Citys Jamaica Bay, we arrive at a Tsimane settlement called Chacal Gringolandia, Gurven says softly as several Coleman tentsGurvens base campcome into view The Tsimane dont live in tents Theres no central village per se, just a freshly painted yellow school house next to a field where the men play soccer nightly The Tsimane live scattered along the river, each family or group of families tending fields of rice, corn, and manioc Some credit their decentralized way of life with helping them resist Spanish influence The would be colonizers found no central authority to usurp, no priests or kings to co opt And the Tsimane simply retreated deeper into the jungle before the Spanish advance, which began in the seventeenth century Soon enough, were walking along a narrow path running parallel to the river As a clearing becomes visible through the underbrush, a Tsimane guide with a boyish face and solemn demeanor named Arnulfo makes a soft hooting sound Gurven takes up the call as well High pitched and elongated like the last syllable of an owls hoot, the cry serves as a kind of jungle courtesy, notifying those up ahead that were approaching As we pass into the clearing, Gurven and Arnulfo announce their greetings in Tsimane A group of young boys plays with tops carved from tree nuts Hammered in nails serve as points The children stare at the newcomers expressionless at first, their brows in furrows, but theyve seen outsiders before, and they quickly resume their game, winding string around their tops, and then setting their toys spinning with practiced yanks Two women seated on a large woven mat return the greetings A little girl lies prone in the lap of one woman, who searches patiently through her hair, extracting lice and nits, and crushing them between her teeth The men are all gone for the day, we learn, on a hunting trip We say our goodbyesits not good form to visit the women without men present, Gurven explains laterand continue walking We see fields of corn, lots of dogs, canoes, exquisitely woven mats, waist high mortar and pestles, and everywhere tools made from jungle materials Its this mastery of the jungle that strikes me, a twenty first century New Yorker with a computer addled, Internet spoiled brain, as most impressive The Tsimane carve slim dugout canoes from tree trunks, and push them through the rivers with long poles Mats are woven from palm fronds, as are the roofs on their huts Useful trees and plants surround their jungle homesteadspapaya, banana, and a tutuma tree that bears large gourdlike fruits that they then fashion into bowls They use ginger root to treat insect bites They sleep on elevated platforms As Gurven explains, here, ones worth doesnt derive from ones possessions, but instead from ones skills at extracting resources from the jungle You could lose everything, yes, but then you just build a new house, get fish, go hunting Lots of individuals have that ability, he says Theres a kind of freedom in that I could go on about how extraordinary Tsimane adaptations are, but really, Im here to observe what I cant see directly the hidden microbial and parasitological landscape I want to know what that place where the immune system doesnt malfunction looks like And so how does it look The answer is, alive To Gurvens chagrin, the Tsimane often draw drinking water directly from the muddy river Its likely teeming with bacteria Pigs, chickens, dogs, and the occasional pet spider monkey wander about freely They each bring their unique blend of microbes Tsimane women make an alcoholic drink by chewing and spitting boiled manioc and letting it ferment In other words, they regularly imbibe what your average New York health food store touts as live cultures And of course, a majority has hookworms embedded in his or her gut In short, the Tsimane live in what scientists call a living environment Who cares Much evidence suggests that surroundings like this protect against autoimmune and allergic disease, and for a simple reason This is the type of environment the immune system has evolved to expect And when it doesnt encounter the abundant stimulation contained herein, it falls into disarray Life here is not easy, of course.16 Infant mortality, which has improved since vaccinations arrived during the 1990s, remains high One in five children dies before his or her fifth birthday By age fifteen, an additional 5 percent have succumbed to disease Essentially, one quarter of all children born dont survive to adolescence, and thats an improvement over the early twentieth century On the other hand, two of every five Tsimane live to age sixty, one of Gurvens central and somewhat counterintuitive findings Despite the ubiquity of infectious and parasitic disease, however, the Tsimane do not appear sickly or starving Theyre often missing several front teeth, a result of their fondness for sugarcane and citrus fruit, says Gurven, but otherwise, they seem robust and healthy On our return trip, well motor down the river, and drive through cane fields on muddy dirt roads To return home, Ill take a small plane from San Borja over the imposing wall of the Andes to the west, spend a layover in the nations capital, 12,000 foot high La Paz, and then head back to New York City via Miami in a jet That trip passes through a well defined gradient of allergic disease Ill have traveled from an area of nonexistent allergies subsistence living in the jungle to one of slightly higher the no frills Bolivian town to one of even higher a large city in a developing country to a place with the highest allergy prevalence of all a large city in the developed world The gradient I just described in space also exists in time If you retrace your own lineage back a few generations, youll probably find hay fever and asthma lessening with each one You like me may have lifelong asthma and food allergies, for example Your parents, meanwhile, maybe had seasonal hay fever But relatively few of your grandparents generationor great grandparents, as the case may besuffered from sneezing or wheezing of any sort.17 This pattern likely relates not to new exposures, but to the removal of old onesexposures of the sort still prevalent in Tsimana Repeated observations like these, backed by piles of experimental evidence indicating that the immune system responds differently depending on its history of exposures, have prompted some immunologists to question the basic assumptions underlying their field Our understanding of the immune system rests on work mostly carried out during the twentieth century, but by that time, we were living in evolutionarily novel circumstances In other words, we may have made a mistake equivalent to studying and cataloging an exotic seeming ecosystem, only to discover that we werent in the jungle at all we were actually at the Bronx Zoo Or as the Duke University scientist William Parker puts it, We as immunologists are now faced with the unsettling realization that the immune system we have spent all of our effort and energy studying overthe past fifty years has turned out to be dramatically different than the system derived by natural selection.18 And that brings us to the heart of the matter UNDERSTANDING THE IMMUNE SYSTEM AND ITS DISCONTENTS Youve probably heard peripherally about the many allergens, such as dust mites, peanuts, and tree pollen, which cause allergies Maybe youve heard reference to the infections and toxic pollutants that provoke autoimmune disease Without suggesting that these ideas are totally unfounded, heres an alternative and much simpler model for engendering immune dysfunction To produce these disorders, you dont need to add something new to your body All thats necessary, in fact, is the removal of a single critical component of the immune system, and the human organism will collapse in a firestorm of autoimmune and allergic disease Immunologists learned this lesson from real life case studies In 1982, scientists at Oregon Health Sciences University in Portland described the case of an infant whod died from multiorgan autoimmune diseasetype 1 diabetes, thyroiditis, eczema, diarrhea, and a self destructive immune response to viral infection.19 Seventeen other male infants from the boys extended family had perished the same way, but no girls The scientists suspected they had a genetic mutation in the X chromosome on their hands Boys have only one X chromosome, from Mom So while girls, who have an X chromosome from each parent, can always refer to workable instructions in their second X chromosome, boys are stuck with whatever defective genes their single X chromosome contains These boys had apparently inherited a gene that precipitated an immune system meltdown Two decades passed before geneticists identified the culprit The gene was named FOXP3 forkhead box P3 in its full ungainliness.20 When switched on, FOXP3 changed how white blood cells operated, turning them from aggressors into peacekeepers In the case of those boys, a spontaneous mutation had disabled the gene As a result, they couldnt restrain immune aggression They went thermonuclear on invaders, causing severe collateral damage And they couldnt tolerate even their own tissues Mystery solved Case closed Except that the finding upended the current understanding of the immune system.21 For decades, immunologists had envisioned a system that avoided attacking the self by deleting self reactive immune cells, and by employing the molecular equivalent of a hall pass system Cells that belongedyour cellsdisplayed a unique badge called the major histocompatibility complex, or MHC Invaders didnt have this badge, and patrols picked them off handily But here we had cells that possessed the mark of belonging, and were attacked anyway Whats , healthy individuals tolerated a teeming community of microbes in the gut, organisms that didnt display the requisite hall pass but nonetheless escaped notice Clearly, the old ideas needed revising Scientists, meanwhile, experimentally produced a range of autoimmune disorders by doing exactly what the FOXP3 mutation had donedisabling or hindering peacekeeping cells Self directed white blood cells obviously existed in healthy animals they were a natural part of a functioning immune system Order was maintained not by destroying these cells, but by restraining them Disease arose not because lunatic lymphocytes escaped extermination the old thinking , but because ineffective or absent suppressor cells failed to rein them in The allergic and autoimmune diseases bedeviling us in modernity stemmed from a failure to police the police By the late 2000s, a revised model had emerged Soon after birth, a wave of autoimmune cells populated the organism They helped in defense, anticancer immunity, and tissue repair A wave of peacekeeping cells quickly followed these initial pioneers, restraining them and establishing equilibrium But keeping the peace in the long run required suppressor cells This secondary squadron emerged only after contact with the outside worldwith certain parasites and microbes This dependence was truly weird It meant that our ability to self regulate, to maintain homeostasis, was oddly reliant on external stimuli What a design flawunless you considered the human organism in its proper context By all measures save sheer size and weight, youre mostly not you at all The commensal bacteria in your gut, maybe 3 pounds worth, outnumber your cells by ten to one The collective genome of this microbial community is a hundred times larger than yours, a hefty novel to your trifold pamphlet That community harbors representatives from the three major branches of life on earth bacteria prokaryotes , yeasts eukaryotes , and archaea microorganisms that inhabit, among other extreme niches, deep sea hydrothermal vents You are really an ecosystem, a mutually dependent aggregation of life forms, what scientists call a superorganism Now the reliance on external inputs makes a little sense How could your genetic selfthe You that began when Dads sperm fertilized Moms eggpossibly ignore the voice of the majority The seemingly absurd mistake that prompts immune mediated disease makes a little sense as well Remove or change those stimuli, and of course youd expect the immune system to lose its bearings Those signals both guide and stabilize your immune function And that, unfortunately, is the story of the past centurythe reason some think that the human immune system now malfunctions so spectacularly We routinely fail to tolerate everythinginnocuous proteins allergies , our own tissues autoimmune disease , and our commensal flora inflammatory bowel disease because weve done environmentally what that FOXP3 mutation did genetically By changing our inner ecology, weve hobbled the critical suppressor arm of our immune system So heres the question Can we replace these stimuli Can I take whats protective about the Tsimane environment and reintroduce it to mine And can I do it without killing myself in the process, without losing the unprecedented improvement in both quality and length of life that characterizes the developed world INFESTED WITH WORMS IN MEXICO And that brings us back to my impending experiment I pull off the highway into a eucalyptus lined parking lot where Ill meet my hookworm donor, a medical school dropout named Garin Aglietti Warehouse sized outlets of major American brandsMarshalls, Nike, Levis, McDonaldssurround us I join a group of forlorn looking elderly people waiting under a tent A bus passes by here to ferry them across the border They belong, I presume, to the daily migration of Americans who travel to Mexico to buy cheap drugs Aglietti arrives in a tan Jeep Cherokee with Nevada plates Hes wearing baggy jeans, a blue shirt, and silver rimmed wraparound sunglasses He removes them to reveal blue eyes in a round, open face In brief, Agliettis story goes like this In the 1990s, he developed psoriasis, an autoimmune disorder of the skin Hed also suffered from asthma for most of his life Mostly he fretted over the conditions known to accompany psoriasis, such as cardiovascular disease and autoimmune arthritis All too frequent chest pains incited a cascade of worry I felt like it was killing me, he tells me I was way too young to be getting chest wall pain Allopathic medicinealso known as modern medicinedidnt offer much by way of treatments Then in the early 2000s, Aglietti heard about a Japanese scientist named Koichiro Fujita Working in Borneo in the 1990s, a time when Japanese children seemed increasingly prone to developing eczema, Fujita had noticed that Bornean children had exquisite skin and no allergies They also harbored plenty of parasites Was there a link Back in Tokyo, Fujita took the extraordinary step of self infecting with tapeworm His hay fever cleared up His skin became clearer and less muddled He started preaching that the modern world was too clean for our own good Corporate funders began withdrawing support from his lab Aglietti decided to follow Fujitas lead Tapeworms have an intermediate and definitive host In the former, they form a cyst in the latter, they live as an intestinal worm In 2005, Aglietti traveled to Kenya, toured cattle slaughterhouses searching for tapeworm cysts, found two, and swallowed them Soon thereafter, Agliettis psoriasis plaques softened A few months later, theyd almost entirely disappeared But once a tapeworm matures, it begins releasing rather large, semi self propelled egg filled sacks called proglottids They slither out ones rear and down ones leg in search of new intermediate hosts When they began passing, Aglietti felt as if sweat were dripping down his leg in the absence of any perceivable heat Its just a very unclean feeling psychologically, says Aglietti I just couldnt deal with it He terminated the experiment with antiworm drugs After passing a three foot long tapeworm, he set off in search of another, less psychologically disturbing parasite This time, he settled on hookworm Now he sells hookworm to others in Tijuana As we walk along the highway toward Mexico, Aglietti asks me almost gingerly why, with my apparently extensive knowledge of parasites, I didnt travel to some corner of the developing world, as he did, and acquire parasites naturally I dont have the time, I say But as we pass through turnstiles into a walled corridor, the no mans land that separates the two countries, Im wondering the same thing No doctor or scientist Ive yet met would recommend traveling to Tijuana to acquire hookworm Not only is this approach completely outside the realm of whats proven to work scientifically, those like Aglietti who offer the serviceat least two operations exist as of this writingdo so outside the scientific and medical establishment No standards of quality or care exist save those that are self imposed And theres just as little accountability if anything goes wrong The cons of what Im about to do are therefore significant Illness and death are the most obvious But Im most worried about encouraging Aglietti, who seems perfectly nice, and his ilk Im not sure they deserve attention than theyve already received On the other hand, self infecting with hookworm has become an underground phenomenon of sorts, an unconventional treatment for often desperately ill people I want to see what these individuals go through, how the process works And that brings me to the pros Ive heard fantastic tales of remission from people whove come this way before Some I can confirm Many I cannot Theres nothing like seeing with your own eyes to settle questions like these The potential benefits are also considerablenot worrying about peanuts, not wheezing, no hay fever, no red, swollen eyes when cats jump in my lap Sprouting a full head of hair would really be icing on the cake Most important, success might point the way toward the Holy Grail of preventionnot for me, but for my children We pass through another revolving gate thats strangely reminiscent of the unjumpable, floor to ceiling turnstiles in the New York City subway, and were suddenly at a small plaza with a fountain in Mexico No American chain stores Small shops with colorful signs dominate A friendly young man with thick black eyebrows and hair gelled into spikes pulls up He drives us to a neighborhood near the ocean We park in front of building with a Mexican flag waving from the second floor balcony A sign says UNIDAD DE MEDICINA HOLSTICAOffice of Holistic Medicine While Aglietti confers with the doctor upstairs, our driver, Andrs, the doctors son, tells me hes twenty years old, and was just admitted to medical school He adds that his lifelong asthma forced him to stop playing sports years ago Some months ago he infected himself with hookworm, and now its much better He began playing soccer again Aglietti returns and tells me the doctor is ready I follow him to a clean, spare office on the second floor A T shirt with SAY HELLO TO MY LITTLE FRIENDS over an image of a gaping hookworm mawfour flat fangs lining the top, and vague indents where the eyes should beis pulled over the back of a chair The four teeth suggest Ancylostoma duodenale, generally considered pathogenic than the Necator americanus Ill receive today N americanus has just two teeth that are boxier and, somehow, less sinister looking Dr Jorge Llamas enters, dressed in black slacks and blazer, and worn black loafers He has a paunch, jowls, and a robust head ringed with trimmed white hair Others whove passed this way have expressed great affection for him, and I can see why He projects an easygoing, friendly manner thats reassuring and soothing Were divorced from nature, he tells me And its hurting us He relates a story about an American woman who, after having lived in Acapulco for a time, returned to the U.S to find shed acquired parasites She had them removed Suddenly she was diagnosed with Crohns disease He mentions that as a child in Guadalajara, his father took him to the beach often, where swarms of mosquitoes fed on him It made my immune system strong, he says Hes never had allergies He rails against the modern obsession with cleanliness Everyone is mindlessly following the U.S.s lead, he says And everyone is getting U.S diseases We need to stop and think He ends his holistic doctor spiel to take my medical history Do I wake up at night Yes How many times, and what happens when I do I go back to sleep Just go back to sleep Yes How often do I exercise Three times a week Whats my religion None That must be a lonely existence, he says, and notes something on my chart He begins explaining the known emotional states associated with asthma and alopeciastress and depression, respectively We create our own realities, he says at one point Were even creating this reality right now As we continue drifting into what Im fairly sure is pseudoscience, I grow disconcerted Im here to acquire parasites, which is among the stupider things Ive done But the experiment is meant to probe what I imagine are universal principles of systems biologyrelationships forged over mind numbingly long periods of coevolution None of which is hocuspocus I attempt to correct course I ask to see Agliettis blood work Ive found no evidence that hookworms can transmit viruses between people, but theyre born as eggs in one humans bowel movement and, after hatching into larvae and piercing the skin, they pass directly into another humans bloodstream The precautionary principle applies Soon were shuffling through a year or twos worth of tests I confirm that Aglietti is clear of the major virusesHIV, cytomegalovirus, hepatitisas well as Strongyloides stercoralis, a nasty worm that, uniquely among soil transmitted helminths, can reproduce in the host Im as satisfied as Im going to be Are you nervous asks Llamas Do I look nervous He shrugs A little We move to a room at the back of the building Aglietti has donned a light blue doctors overcoat with Worm Therapy embroidered in script over his right pectoral Hes smiling and seems excited With a pipette, Llamas removes what Im assuming is larvae laden water from a beaker, and squirts it onto an absorbent bandage Given my apparent health, Aglietti and Llamas have recommended thirty worms, not the twenty or twenty five I was assuming The bandage goes on Within a minute, I feel a tickling, itching, nearly burning sensationrather like a mild case of stinging nettles Thats the microscopic larvae burrowing through my skin Before anyone knew a parasite caused it, the distinctive itch had gained notoriety around the world, earning monikers like ground itch, miners itch, water pox, or the poetic dew poison Now scientists understand that hookworm larvae leave their outer cuticle, discarded inside out like a sock, embedded in your skin Your immune system responds savagely But the now naked larvae are already long gone Each larva will find its way into a capillary, and hitch a ride on my venous blood flow, like rafters on a river Theyll pass through the thunderous pump of my heart, which causes me no small degree of anxiety And once theyve arrived at the capillaries of my lung, theyll burrow out of the circulatory system, into the bunch of grapes like sacs called alveoli Theyll then follow the coordinated sweeping motion of millions of hair like cilia up and outwardthe so called mucociliary escalatorover the pharynx, where windpipe and food pipe branch, and plunge down into the esophagus Theyll miraculously survive the hydrochloric acid bath of my stomach and finallyafter an odyssey through my body lasting several weeksarrive at my small intestine, the final destination Theyll latch on to my intestinal wall Theyll mate Large individuals will reach a centimeter in length The females will lay perhaps 10,000 microscopic eggs daily, all the while grazing on intestinal tissue to the tune of 0.04 milliliter of blood per day Assuming they all survive, thats eight drops for every ten worms, or twenty four drops daily paid to host a thirty strong colonynot much, but not nothing either And they can live for five years, maybe longer The eggs, which require a week or two in tropical conditions to become infective larvae, will pass out with my stoolwhich, in New York City, means they end up in a wastewater treatment plant I might get a mild cough in a week or so, Aglietti explains Flulike symptoms are common Then epigastric pain once the worms attach If I start coughing, I shouldnt spit out the discharge Swallow it, he says Thats your medicine Then Aglietti, whos periodically glanced at his wristwatch since the bandage went on, says, Okay, were past the possibility of anaphylaxis Hes referring to a potentially fatal allergic reaction usually associated with bee stings or, these days, peanuts Anaphylaxis is treated with a shot of Adrenalin, which he has handy Llamas hands me a box containing three pills of mebendazole, a deworming drug This is your out, he says Here in Mexico we take two But in the U.S., being the U.S., they take three By now I have a headache Im filled with feelings of disgust, hope, and wonderdisgust with myself for agreeing with myself to this experiment hope that the experiment may do some good and wonder at the parasites biology, its ability to pierce skin, navigate circulatory systems, and, in the coming weeks, arrive at my small intestine Underlying these sentiments is a recently acquired, quasi religious faith in evolutionconfidence that the organism knows what its doing, and wont kill me in the process For an obligate parasite, a dead host is, after all, a useless host For better or worse, were now in this together.RemarkableMoises Velasquez Manoff draws together hundreds of studies to craft a powerful narrative carrying a fascinating argument Wall Street Journal A reportorial journey into a frontier of science and health Wired About the Epidemic HHS Opioid overdoses caused than , deaths in any previous year on record In HHS declared a public health emergency to combat crisis Inside Killer Drug A Look at America s Jan The opioid epidemic killed people What follows are stories of national affliction that has swept country, from cities West Coast Text neck is becoming an and could wreck your human head weighs about dozen pounds But as bends forward down, weight cervical spine begins increase At degree angle, this pounds, The Ghost Map Story London Most Terrifying How It Changed Science, Cities, Modern World Steven Johnson FREE shipping qualifying offers National Bestseller, New York Times Notable Book, Entertainment Weekly Best Book Year summer Spanish flu Wikipedia influenza pandemic January December colloquially known Spanish was unusually deadly pandemic, first two pandemics involving HN virus infected million around world, including remote Pacific islands Arctic, resulted three five percent WHO Violence against women global problem proportions clinical policy guidelines launched guide sector response Crack History South Central, Los Angeles Crack form drug cocaine one most highly additive destructive drugs world Small doses it smoked into Home CEPI CEPI alliance finance coordinate development new vaccines prevent contain infectious disease epidemics Is Autism or Are We Just Noticing More Jul March US Centers for Disease Control Prevention CDC newly measured autism prevalences olds United States, headlines roared An Epidemic of Absence: A New Way of Understanding Allergies and Autoimmune Diseases


    • An Epidemic of Absence: A New Way of Understanding Allergies and Autoimmune Diseases
    • 4.3
    • 577
    • Format Kindle
    • 416 pages
    • 1439199396
    • Moises Velasquez Manoff
    • Anglais
    • 06 April 2016

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