Infectious Madness

CHAPTER 1

Germ Theory Redux: The Acquisition of Mental Illness

"When I was a student in the 1960s, I once saw a man in the final stage of syphilis," recalls English writer John Cornwell. "He was a patient on a psychiatric ward in London where I was working. White-haired, olive-skinned, emaciated, without a name or known country of origin, he had been picked up from a gutter in the London docks."

The man lived in a state hospital for the mentally ill, where he was cared for by a kind but resigned staff. "He stood all day in the corridor leaning against the wall, doing a slow-motion foot shuffle." The man, Cornwell tells us, was more than psychologically impaired. He could not hear or speak and seemed oblivious to his surroundings. "The ward charge nurse assured me that he was 'unlucky, the last of his kind.' He had not been given treatment in time to halt the final devastation of the disease."¹

Cornwell's account reminded me of a patient I had encountered while working in an upstate New York county hospital in the 1960s. He was probably in his early sixties, but he looked younger, thanks to his vacant gaze and unfurrowed brow. Dressed in khaki pants and a T-shirt,² he was gently propped in front of a peeling greenish wall every day, and he remained there, a slight smile playing about his lips, his equanimity undisturbed by the chaos and noise of the behavioral renegades with whom he shared the dayroom. Once, he was placed too close to the naked bulb of a torchère lamp whose shade had been lost in some forgotten drama, but when a staff member moved it to a safe distance, he neither averted his eyes nor tracked the aggressive glare. He was blind. He was also deaf, unable to speak or communicate, and he showed no signs of being able to reason or remember. He was reduced to someone who ate and defecated, who was bathed and dressed and shuffled along to nowhere with utter indifference. No one ever visited him.

What had happened to this man? The aide shepherding him to dinner whispered, "He's got paresis, and it has destroyed his brain. It's an old disease, you never see it now. He was treated with penicillin, but they can't bring back the lost function."

Lost. I hung on the adjective, which seemed to capture his condition so perfectly. Then I did a double take. "Penicillin? An antibiotic? For a severe mental disorder?" The aide shrugged as she and her charge moved on.

The antibiotic was in order because general paresis, a form of neurosyphilis, is seen in the late stages of syphilis and can emerge twenty to thirty years after the initial infection. Because it attacks in a very nonspecific manner, the neurosyphilis infection can appear in many different ways and damage many different areas of the brain. Whatever region comes under fire by the bacteria and their antibodies determines the disease's signs and symptoms, which are legion. In both Cornwell's patient and in the upstate New York man I observed, aural and visual systems had been destroyed and motor functions reduced to stereotyped residual movements. This damage can cause delusions, hallucinations, a diminished ability to think or speak, personality changes, impaired judgment, anger, irritability, and a sad or depressed mood. Both short-term and long-term memory may eventually disappear. There are physical consequences too, including changes in the pupil of the eye, overactive reflexes, sharp pains, a slow degeneration of the neurons' ability to transmit messages (somewhat like that seen in multiple sclerosis), and profound muscle weakness, all of which eventually relegate paresis sufferers to bed.

The New York man was treated in a general hospital, but the man with paresis whom Cornwell encountered in England was being treated by psychiatrists in a mental institution, as befitted his profound dementia and psychological and mental losses.³ If one had to choose between the two labels, this clearly was mental illness. Or was it? Given that a paresis patient is dogged by the loss of control over his movements, loss of vision, and other physical problems, and given that all this carnage resulted from a bacterial infection, was this not a physical disorder? For that matter, does one have to choose?

"There may be said to be two classes of people in the world," mused Algonquin Round Table habitué Robert Benchley in 1920, "those who constantly divide the people of the world into two classes, and those who do not."⁴ Physicians belong to the first group. They embrace the long-standing mind-body dualism that insists that mental disorders solely affect the mind, and physical disorders are the product of distorted physiology.

The fact that psychiatric diseases are now routinely located in brain dysfunction doesn't resolve the issue, because this acknowledgment doesn't necessarily represent a dissolution of the imaginary boundary between the physical and the mental. Instead, this stance often entails a belief in two distinct species of "mind." In one, consciousness and mental disorders are created by and dependent on the functioning of the brain, a sort of ghostly extension of the brain into psychic space. The other mind is viewed as completely separate from the brain. But without a specific indication of precisely which mind is meant, the scientific literature is often maddeningly fuzzy and unhelpful.

To what extent is automatically ascribing mental disease to psychological trauma and genetic determinism and physical disease to tangible environmental causes just a lazy habit of thought?

For ancient Greeks, the distinction between psychological and medical illness was not the most salient or definitive characteristic of disorders. In Hippocrates's disease taxonomy, mania, melancholia, and hysteria were treated with the same humoral-imbalance corrections that he prescribed for physical illnesses.

At the other extreme, there's a long history of attributing psychosis to moral failure. In Deuteronomy 28:27–29, rebellious Israelites were threatened with insanity. "The Lord will smite you with madness, blindness and with bewilderment of heart," it promises. Medieval scholars and theologians believed madness was spiritually induced, either by a failure of faith or by a punishment from the gods, a theory that died hard and that, arguably, persists in pockets of fundamentalism and faith healers.

However, by the time of the Renaissance, physicians and other Western medical experts placed mental diseases firmly in the fold of physical ailments and treated them as such.⁵ This view persisted for centuries. "From the Renaissance until the second half of the 18th century," wrote R. E. Kendell in the British Journal of Psychiatry, "melancholia and other forms of insanity were generally regarded as bodily illnesses not differing in any fundamental ways from other diseases." Even the famous psychiatrist Karl Menninger hypothesized in 1922 that schizophrenia was "in most instances the byproduct of viral encephalitis." And although it seems counterintuitive to suggest that humans can catch depression or schizophrenia in the same way we catch the flu, this hypothesis springs from germ theory, developed by Louis Pasteur in the 1860s and Robert Koch in the 1870s, which posits that specific microbes such as bacteria, viruses, and prions (infectious proteins) cause illness.⁶

Although most people think only of physical illness, not mental disease, when they think of germ theory, pioneering psychiatrists like E. Fuller Torrey, the executive director of the Stanley Medical Research Institute (SMRI), have sought to change this. Torrey has long rejected the relegation of mental disease to psychological causes alone and has spent the last half a century tracing the relationship between infection and mental illness.

In the 1990s, Torrey observed that in the late nineteenth century, schizophrenia and bipolar disorder went from being rare diseases to relatively common ones. During the same period he noticed that owning cats as pets replaced regarding them as Satan's minions, relegating them to barns for rodent control, and burning them to celebrate important holidays.

Around the time that England's first cat show was held at the Crystal Palace, in 1871, cat ownership became popular in America. That same year brought a sharp rise in U.S. schizophrenia rates⁷ (except among rural Hutterites, who "almost never" keep cats as pets). Cats carry a zoonotic infection (a disease humans acquire from animals) that causes schizophrenia.

In this case, Torrey suspected Toxoplasma gondii, an infectious single-celled organism discovered in 1908 by Charles Nicolle and Louis Manceaux of Paris's Institut Pasteur. The parasite lives in the tissues of many warm-blooded animals, but it can reproduce only within the stomachs of felids (domestic cats and other members of the family Felidae), making its survival dependent on access to cats. Most healthy adults are unaffected or only mildly sickened by a T. gondii infection, but it produces a variety of serious ailments, including toxoplasmosis, in those with compromised immune systems and in young children with immature immune defenses.

Successful Victorian English artist Louis Wain (1860–1939) was best known for his drawings, which featured large-eyed anthropomorphized cats. Wain spent his last years in a mental hospital where he had been diagnosed with schizophrenia and his images have been used in psychiatric textbooks to document the supposed deterioration of his art as his mental health worsened.

Torrey and his frequent research partner Robert Yolken of Johns Hopkins University have investigated the roles of influenza, T. gondii, and other pathogens in mental disorders. They undertook this research nearly a half century ago, when Freudian and psychosocial paradigms defined mental illness. As the next chapter explains, their efforts helped to shift this paradigm.

A microbial revolution

In his landmark book The Structure of Scientific Revolutions, Thomas Kuhn explains that those in the humanities—people who study, for example, eighteenth-century English literature, African American history, or German existentialism—are free to select the most convincing perspectives, assumptions, and causal frameworks within which to interpret their facts, but scientists are bound by a shared overarching theory. Kuhn defines that worldview, or Weltanschauung, as "what members of a scientific community, and they alone, share."

A paradigm shift is a revolution, for it seeks to overturn the prevailing worldview. But such an overturning is not to be undertaken lightly, because the scientific community's work, careers, and economies rest on the existing paradigm, and to nullify it is to cross the Rubicon, forever abandoning the rules that had previously defined scientific thought. Having embraced the theory of evolution, scientists cannot return to creationist myths to explain the variety of animal life. Having embraced germ theory, scientists cannot revert to believing that sin, demons, or wandering wombs cause madness or that malarious airs increase one's risk of contracting malaria. We are stuck, as it were, with what we know.

So we must choose our revolutions carefully. Yet the one this book describes—the recognition of infection as an important cause of mental illness—may have already begun; most of us just haven't realized it yet.

I say this because revolution takes place when anomalies arise that the existing worldview cannot explain. For example, it is hard to think of schizophrenia as a genetic disease when genetically identical twins are discordant—that is, when only one of the duo becomes schizophrenic. Such an anomaly doesn't immediately trigger researchers to discard the theory; in fact, many such anomalies are tolerated (or ignored) until a sort of critical mass accumulates that throws the field into "a state of crisis," according to Kuhn. New theories are then proposed, although sometimes they are not really new but ideas that have periodically resurfaced, been marginalized, decried as heresy, and forgotten. The hypothesis that infection causes or encourages common mental illnesses—and some uncommon ones—is an example, because as potential paradigm shifts go, it is a perennial. As I noted above, the theory has been with us since ancient times and reappears intermittently as part of the Western medical paradigm.

No one is suggesting that infection should completely replace stress, genetics, and psychological trauma as an explanation for mental illness, just that infection complements them and joins them as an important causative factor. And it is sometimes the primary factor.

The idea that a case of the flu might consign one to madness sounds fanciful. But consider that we are just now discerning the infectious roots of old familiar physical illnesses, many of which had been supposed to have psychological or behavioral triggers.

Cervical cancer, for example, was long ascribed to sexual immoderation in women and poor hygiene in their male partners, but it is now known to be the legacy of infection by strains of the human papillomavirus, HPV. Ninety percent of ulcers, which were once blamed on a spicy diet and uncontrolled stress, are now known to be caused by Helicobacter pylori. Contrary to the theory that held sway as late as the 1990s, heart disease is not a product of having a tense, hostile, angry type A personality but, often, of infection by bacteria including Streptococcus tigurinus and Chlamydophila pneumoniae.

Bacteria, viruses, parasites, fungi, and the infectious proteins called prions are surfacing as possible causes of mental illness as well, a theory that explains many previously mysterious anomalies. Schizophrenia, for example, has been traced to waves of influenza epidemics as well as to infections with bornavirus; species of adolescent anorexia and Tourette's syndrome have been connected to streptococcal infections that affect the basal ganglia; and autism is linked to marauding infections from children's own guts. This book explores the evidence for all of these and more.

Cartesian skirmishes

In the seventeenth century, René Descartes posited the existence of two fundamental kinds of substance: mental and material.⁸ According to this Cartesian dualism, the mental has no spatial existence, and the material cannot think. Substance dualism became popular among scientists and clerics alike, perhaps because it does not preclude the religious belief that immortal souls occupy an independent realm of existence distinct from that of the physical world.⁹

But dualism is far more than a philosophy in medicine; it has long been a political stance as well, adopted as the default position that legitimized and laid a scientific veneer over the struggle of physicians to dominate medical care. Based in part on this theory of dualism, physicians were able to gradually appropriate the care of the physically ill from the clergy, who had established the religious hospitals that had originally assumed the care of the sick.

Still, although the law often required at least one resident physician in a psychiatric hospital or asylum, during the centuries before the discovery of effective medication, doctors were content to leave the care of the mentally ill to the clergy and nuns. However, the majority of the mentally ill were not confined to institutions. Michel Foucault has observed that madmen were allowed to roam freely in medieval Europe and temporarily confined only when their behavior became extreme enough to pose a threat. Moreover, such confinement was long the prerogative of the family, not the doctor. "From the seventeenth century to the nineteenth century, the right to demand the confinement of a madman belonged to the family: it was the family, first of all, that excluded madmen."¹⁰