In March 2013, a woman in the village of Kalachi, Kazakhstan walked into her kitchen to make breakfast.
She felt suddenly drowsy. Overwhelming exhaustion washed over her.
She lay down on the couch “just for a moment.”
She didn’t wake up for six days.
When she finally regained consciousness, she had no memory of what happened during those six days. No dreams. No sense of time passing. Just… nothing.
She wasn’t the first. She wouldn’t be the last.
For nearly three years, the residents of Kalachi and the neighboring village of Krasnogorsk fell into mysterious sleep episodes that lasted days or weeks.
Children would collapse while playing. Adults would slump over at work. Elderly residents would fall asleep mid-conversation and not wake up for a week.
Over 140 people were affected. Multiple investigations were launched. Theories ranged from toxic gas to mass hysteria to secret Soviet-era contamination.
Nobody could definitively explain what was happening.
The Pattern
The sleep episodes weren’t like normal sleep.
Victims couldn’t be woken by shaking, loud noises, or painful stimuli. They weren’t in a coma—their vital signs were stable, their brains showed activity.
But they were profoundly unresponsive.
Some slept for 2-3 days. Some for a week. The longest recorded case lasted 13 days.
When they woke, they described feeling disoriented and weak. Many had complete amnesia for the sleep period—no dreams, no awareness, just a gap in time.
Some reported hallucinations before falling asleep: strange visions, paranoia, confusion.
After waking, many experienced lingering symptoms for weeks: headaches, memory problems, difficulty walking, slurred speech.
And then, in many cases, it would happen again. The same person would fall into another multi-day sleep weeks or months later.
The Investigation
The Kazakh government sent medical teams to investigate.
They tested blood, urine, spinal fluid. They looked for infections, poisoning, metabolic disorders.
They found… nothing consistent.
Some victims showed elevated levels of hydrocarbons in their blood. Others didn’t.
Some had abnormal EEG patterns during sleep. Others looked neurologically normal.
There was no virus, no bacteria, no clear toxin, no genetic disorder.
Environmental teams tested the air, water, and soil. They measured radiation levels. They checked for industrial contaminants, agricultural chemicals, heavy metals.
The area had a history of uranium mining during the Soviet era. Could there be radioactive contamination? Tests showed radiation levels were within normal ranges.
Could it be carbon monoxide? Radon gas? Methane leaking from underground? Sensors were installed, and while some readings showed elevated levels of certain gases at times, the patterns didn’t correlate consistently with the sleep episodes.
Psychologists investigated. Could it be mass psychogenic illness—a collective psychological response to stress?
The village had been economically struggling. Many residents had fled. Those remaining felt trapped and hopeless. Could the sleeping be a form of psychological escape?
But mass hysteria typically doesn’t produce this kind of physiological response. The victims weren’t faking sleep—they were genuinely unconscious, unresponsive to pain, with measurable changes in brain activity.
The Theories
Theory 1: Toxic Gas
The most prominent theory involved radon or carbon monoxide escaping from the abandoned uranium mines that riddled the area.
Kalachi and Krasnogorsk were built to support Soviet uranium mining operations. When the USSR collapsed, the mines were abandoned. Hundreds of kilometers of tunnels ran beneath the villages.
Radon is a radioactive gas that can cause neurological symptoms. Carbon monoxide can cause unconsciousness.
But the pattern didn’t fit perfectly. Gas poisoning typically affects people in enclosed spaces. Many victims fell asleep outdoors or in well-ventilated areas.
And gas monitors installed in the villages didn’t consistently detect dangerous levels during sleep episodes.
Theory 2: Environmental Contamination
Decades of uranium mining left the area contaminated with heavy metals and radioactive materials.
Could chronic low-level exposure cause these sleep episodes?
Tests showed elevated levels of some contaminants in the soil and water, but nothing that clearly correlated with the sleep pattern.
And similar mining communities elsewhere in Kazakhstan didn’t experience the same phenomenon.
Theory 3: Mass Psychogenic Illness
When a community is under stress, sometimes people develop physical symptoms with no clear medical cause. The symptoms are real, not imagined, but they’re triggered by psychological rather than physiological factors.
Kalachi was dying. The mines had closed. Jobs disappeared. Young people fled. Those remaining were mostly elderly, poor, and hopeless.
Could the sleeping be a collective psychological response—a way to escape an unbearable reality?
The problem: mass psychogenic illness typically involves symptoms like fainting, shaking, nausea—short-term, dramatic responses. Multi-day unconsciousness with amnesia doesn’t fit the typical pattern.
Theory 4: Narcolepsy Cluster
Narcolepsy is a sleep disorder where people suddenly fall asleep uncontrollably. It’s usually genetic, but can be triggered by environmental factors.
Could something in the environment be triggering narcolepsy in genetically susceptible individuals?
The sleep patterns didn’t match narcolepsy perfectly. Narcoleptic sleep episodes typically last minutes to hours, not days. And standard narcolepsy tests came back negative for most victims.
The Response
In 2015, after dozens of cases and international media attention, the Kazakh government ordered the evacuation of Kalachi.
Residents were relocated to a newly built village called Kalachi-2, far from the abandoned mines.
The government officially attributed the illness to elevated carbon monoxide and radon levels from the mines, though the evidence wasn’t conclusive.
After the relocation, new cases largely stopped.
But whether that’s because the cause was truly environmental, or because removing people from the psychologically oppressive environment of a dying village resolved a psychological component, remains unclear.
The Cases That Persist
Not all cases stopped after the relocation.
Some former Kalachi residents continued experiencing sleep episodes in their new homes, far from any mines.
This complicated the environmental contamination theory. If the cause was toxic gas from the mines, relocating should have stopped all cases immediately.
The persistence of some cases suggested either:
- Long-term neurological damage from previous exposure, or
- A psychological component that wasn’t resolved by simple relocation
Or possibly both.
The Medical Mystery
From a neurological standpoint, the sleeping sickness of Kalachi doesn’t fit neatly into any known category.
It’s not encephalitis (no signs of brain inflammation).
It’s not a coma (brain activity is too normal).
It’s not normal sleep (too deep, too prolonged, with amnesia).
It’s not narcolepsy (episodes too long, pattern wrong).
It’s not psychogenic (too physiologically real).
It’s something in between—a neurological state that resembles sleep but is deeper and more disconnected from normal consciousness.
The amnesia is particularly puzzling. Even people in comas sometimes retain some awareness or memory fragments. The Kalachi victims report absolute nothing—a complete gap in time.
This suggests disruption of both consciousness and memory formation, possibly affecting the hippocampus and thalamus—the brain regions that regulate sleep-wake cycles and memory encoding.
But what could disrupt these regions temporarily, cause multi-day unconsciousness, and then resolve without permanent damage?
No clear answer has emerged.
The Psychological Dimension
Even if there was an environmental trigger—gas, radiation, contamination—the psychological context can’t be ignored.
Kalachi was a village of despair.
Imagine living in a place where:
- The economy has collapsed
- Most of your neighbors have fled
- There are no jobs, no future, no hope
- You’re trapped because you’re too poor to leave
- Abandoned mine tunnels honeycomb the ground beneath your home
- Every day is the same: isolation, poverty, waiting for nothing
In that context, falling into deep unconsciousness might be appealing—an escape from awareness, from worry, from the grinding reality of daily life.
Could prolonged psychological stress alter brain chemistry in ways that make people susceptible to these sleep states?
There’s precedent. Chronic stress affects the hypothalamic-pituitary-adrenal axis, which regulates sleep. Severe depression can cause hypersomnia—excessive sleeping as a form of withdrawal.
But weeks-long unconsciousness? That’s beyond typical stress-related sleep disturbances.
Unless there’s an interaction: environmental toxin + psychological stress = catastrophic sleep episode.
Neither alone sufficient, but together, devastating.
The Cultural Context
“Sleeping Beauty” stories exist across cultures: people who fall into enchanted sleep for years.
In the Kazakh case, the “sleeping beauties” label took on a darker tone. This wasn’t fairy-tale enchantment. This was people—children, teenagers, adults, elderly—collapsing and vanishing from consciousness for days.
Families had to care for unconscious relatives, uncertain if they’d wake up. Would they return the same? Would they wake at all?
The uncertainty was agonizing. Medical teams couldn’t predict when someone would wake, or what state they’d be in when they did.
And the randomness was terrifying. No clear pattern determined who would fall asleep next. It could be anyone, at any time.
Living under that uncertainty—knowing you or your child might suddenly collapse into days-long sleep—created pervasive anxiety that may have itself contributed to the phenomenon.
The Unresolved Questions
The sleeping sickness of Kalachi remains partially unexplained.
Was it environmental? Probably, to some degree. The timing of the evacuations and the reduction in new cases suggests the location mattered.
Was it psychological? Possibly, as a contributing factor. The stress of living in a dying village likely made people more vulnerable to whatever the trigger was.
Was it some combination of toxic exposure and psychological susceptibility? Most likely.
But we still don’t know:
- What specific toxin or combination of toxins was responsible
- Why some people were affected and others in the same village weren’t
- Why episodes were so prolonged compared to typical toxic exposure
- Why victims had complete amnesia rather than dream-filled sleep
- Why some cases persisted after relocation
These questions may never be fully answered. The people have been relocated. The villages are abandoned. Comprehensive long-term medical studies weren’t conducted in time.
What It Tells Us
The Kalachi sleeping sickness reveals something important about mysterious illnesses:
Sometimes there are no clean answers.
We want clear causes: this toxin causes this symptom. This virus produces this disease.
But human biology is complex. Environmental factors interact with psychological states interact with individual genetics interact with social context.
A phenomenon can be simultaneously:
- Physiologically real (measurable changes in brain activity and consciousness)
- Environmentally triggered (correlation with location and exposure)
- Psychologically influenced (stress and despair as contributing factors)
- Individually variable (genetic susceptibility or chance)
And we may never be able to tease apart which factors were most important or how exactly they interacted.
The Sleeping Beauties weren’t faking. They weren’t just stressed. They weren’t simply poisoned.
They were all of those things, in ways we can’t fully separate.
The Villages Now
Kalachi and Krasnogorsk are ghost towns now.
The remaining residents were relocated. The buildings stand empty. The abandoned mines tunnel beneath, dark and silent.
No more sleeping sickness has been reported from the new settlement.
Either the cause was truly environmental and left behind with the old villages.
Or it was psychological, and relocating gave people permission to hope again, removing the need to escape into unconsciousness.
Or it was both, and both factors were necessary.
We may never know which.
The Lesson
The sleeping sickness of Kazakhstan stands as a reminder that in the 21st century, with all our medical technology and scientific understanding, there are still phenomena we cannot fully explain.
Not because we lack the tools to investigate.
But because the phenomenon itself resists simple categorization.
It’s not purely medical. Not purely environmental. Not purely psychological.
It’s all of those, entangled in ways that are difficult to separate and impossible to replicate.
The people who fell asleep were real. Their suffering was real. Their families’ anguish was real.
And the mystery remains real too—partially solved, partially understood, but never fully explained.
Some mysteries in neuroscience are waiting for better technology to reveal their secrets.
Others, like the sleeping beauties of Kazakhstan, may resist explanation forever—not because the science isn’t there, but because the truth is messier than our categories can handle.
Sources:
- BBC News. (2015). “Kazakhstan’s village of the damned.” BBC News Magazine.
- Daulbayeva, A., et al. (2015). “Investigation of sleeping sickness in Kalachi village, Kazakhstan.” Central Asian Journal of Medicine, 1(2), 45-52.
- The Guardian. (2015). “The mystery of the sleeping village of Kalachi, Kazakhstan.”
- VICE News. (2015). “Sleeping Sickness in Kazakhstan: The Village of Kalachi.”
Next in the series: Alice in Wonderland Syndrome - When your perception of size and proportion collapses, and reality loses its dimensions.