The sleeping sickness of Kalachi,

Kazakhstan Kazakhstan, officially the Republic of Kazakhstan, is a transcontinental country located mainly in Central Asia and partly in Eastern Europe. It borders Russia to the north and west, China to the east, Kyrgyzstan to the southeast, Uzbeki ...

(with the place or the syndrome sometimes called sleepy hollow) is a conjectured medical condition which causes a person to sleep for days or weeks at a time, together with other symptoms such as hallucinations,

nausea Nausea is a diffuse sensation of unease and discomfort, sometimes perceived as an urge to vomit. While not painful, it can be a debilitating symptom if prolonged and has been described as placing discomfort on the chest, abdomen, or back of the ...

, intoxicated behavior, disorientation and memory loss. The phenomenon was only reported in Kalachi and the nearby village of Krasnogorsk. It was first reported in March 2013 and by 2016 had affected about 150 people. The syndrome appeared to be non-communicable. The disease disappeared for some time but re-emerged in 2015, and affected all age groups. Potential causes of the syndrome were suggested to be

carbon monoxide poisoning Carbon monoxide poisoning typically occurs from breathing in carbon monoxide (CO) at excessive levels. Symptoms are often described as "flu-like" and commonly include headache, dizziness, weakness, vomiting, chest pain, and confusion. Large e ...

or contamination of the ground water supply by chemicals used for military operations in the region.

Signs and symptoms

Other than excessive sleep, the disease causes hallucination,

and

vomiting Vomiting (also known as emesis and throwing up) is the involuntary, forceful expulsion of the contents of one's stomach through the mouth and sometimes the Human nose, nose. Vomiting can be the result of ailments like Food-poisoning, foo ...

, and disorientation. Victims of the disease would sometimes act as if they were drunk, would experience memory loss about what they had done and experienced, and would often experience hallucinations like a "snail walking over their face". In a statement, a professor from

Tomsk Polytechnic University National Research Tomsk Polytechnic University (TPU) is a technical university in Russia. TPU was a member of 12 international associations, including the Conference of European Schools for Advanced Engineering Education and Research (CESAER) un ...

, Leonid Rikhvanov, of the department of geo-ecology and geo-chemistry, said that radon gas from the mine could be the cause of the symptoms. The affected people would fall asleep during day-to-day activities and always feel sleepy. As a local nurse described the phenomenon to an RT news crew, "You wake them up, they can speak to you, reply to you, but as soon as you stop talking and ask what bothers them, they just want to sleep, sleep, sleep."

Cause

Kazakh officials gave a report about the disease, stating that heightened levels of

carbon monoxide Carbon monoxide (chemical formula CO) is a colorless, poisonous, odorless, tasteless, flammable gas that is slightly less dense than air. Carbon monoxide consists of one carbon atom and one oxygen atom connected by a triple bond. It is the simple ...

, along with other

hydrocarbons In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. Hydrocarbons are examples of group 14 hydrides. Hydrocarbons are generally colourless and hydrophobic, and their odors are usually weak or ex ...

due to flooding of an abandoned Soviet-era

uranium mine Uranium mining is the process of extraction of uranium ore from the ground. Over 50 thousand tons of uranium were produced in 2019. Kazakhstan, Canada, and Australia were the top three uranium producers, respectively, and together account f ...

nearby, was causing the syndrome, by spreading through the village's air. Concentration of carbon monoxide and reduced oxygen in the air were concluded to be the reason for the sleeping sickness in these villages. An alternate theory was presented by an epidemiologist and experts from

Nazarbayev University Nazarbayev University (NU) is an autonomous research university in Astana, the capital of Kazakhstan. Founded as a result of the initiative of the first President of Kazakhstan, Nursultan Nazarbayev in 2010 (June), it is an English-medium institu ...

Astana, Kazakhstan Astana, previously known as Akmolinsk, Tselinograd, Akmola, and most recently Nur-Sultan, is the capital city of Kazakhstan. The city lies on the banks of the Ishim River in the north-central part of Kazakhstan, within the Akmola Region, thou ...

, after interviewing the local villagers, suggesting the ailment was caused by chemical contamination of the ground water supply. It was suggested that such chemicals had originated from use by the military and had leaked from barrels, but no particular chemicals were reported to have been identified it was simply suggested that this was a theory worthy of further investigation, based on epidemiology rather than chemical analysis.

References

{{reflist Ailments of unknown cause Sleep disorders