Yunnan Sudden Death Syndrome
Encyclopedia
Yunnan Sudden Death Syndrome is a label used to define unexplained cases of cardiac arrest
, which afflicted significant numbers of rural villagers in Yunnan
province, in southwest China
. Cases occurred almost always during the midsummer rainy season (from June to August), at an altitude of 1800-2400m (5900-7900ft). The cause turned out to be a mushroom now blamed for an estimated 400 deaths in the past three decades.
The mysterious fatalities were recorded for decades before researchers from Chinese Center for Disease Control and Prevention
isolated a significant factor common in every case: a tiny unknown mushroom which was unintentionally gathered and consumed during wild mushroom harvests in the region. Previously the syndrome was thought to be caused by Keshan disease
, caused by the Coxsackie virus.
The mushroom, known as 'Little White' belongs to the Trogia
genus. It has been determined that families collecting fungi to sell, have been eating these Little White mushrooms as they have no commercial value. It has been suggested that three novel (toxic) amino acid
s present in the mushrooms may be the culprit, but this has not yet been conclusively demonstrated. The mushrooms have also been shown to contain very high quantities of barium, and it may be that some of the deaths are simply from barium poisoning.
In the hours before death, about two-thirds of the victims had such symptoms as nausea, dizziness, heart palpitations, seizures and fatigue.
Cardiac arrest
Cardiac arrest, is the cessation of normal circulation of the blood due to failure of the heart to contract effectively...
, which afflicted significant numbers of rural villagers in Yunnan
Yunnan
Yunnan is a province of the People's Republic of China, located in the far southwest of the country spanning approximately and with a population of 45.7 million . The capital of the province is Kunming. The province borders Burma, Laos, and Vietnam.Yunnan is situated in a mountainous area, with...
province, in southwest China
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...
. Cases occurred almost always during the midsummer rainy season (from June to August), at an altitude of 1800-2400m (5900-7900ft). The cause turned out to be a mushroom now blamed for an estimated 400 deaths in the past three decades.
The mysterious fatalities were recorded for decades before researchers from Chinese Center for Disease Control and Prevention
Chinese Center for Disease Control and Prevention
The Chinese Center for Disease Control and Prevention is an agency of the Ministry of Health of the People's Republic of China based in Beijing, China. It works to protect public health and safety by providing information to enhance health decisions, and it promotes health through partnerships...
isolated a significant factor common in every case: a tiny unknown mushroom which was unintentionally gathered and consumed during wild mushroom harvests in the region. Previously the syndrome was thought to be caused by Keshan disease
Keshan disease
Keshan disease is a congestive cardiomyopathy caused by a combination of dietary deficiency of selenium and the presence of a mutated strain of Coxsackievirus, named after Keshan County of Heilongjiang province, Northeast China, where symptoms were first noted. These symptoms were later found...
, caused by the Coxsackie virus.
The mushroom, known as 'Little White' belongs to the Trogia
Trogia
Trogia is a genus of fungus in the Marasmiaceae family. It is named after a Swiss mycologist Jacob Gabriel Trog. The genus contains about 20 species that are widely distributed in tropical areas.-Taxonomy:...
genus. It has been determined that families collecting fungi to sell, have been eating these Little White mushrooms as they have no commercial value. It has been suggested that three novel (toxic) amino acid
Amino acid
Amino acids are molecules containing an amine group, a carboxylic acid group and a side-chain that varies between different amino acids. The key elements of an amino acid are carbon, hydrogen, oxygen, and nitrogen...
s present in the mushrooms may be the culprit, but this has not yet been conclusively demonstrated. The mushrooms have also been shown to contain very high quantities of barium, and it may be that some of the deaths are simply from barium poisoning.
In the hours before death, about two-thirds of the victims had such symptoms as nausea, dizziness, heart palpitations, seizures and fatigue.