The causes, conditions and correlated factors of Keshan disease / 中国地方病学杂志

ABSTRACT

Objective To explore the cause and epidemiologic characteristics of Keshan disease.Methods The cases observation method,epidemiologic methods,fungus-mycotoxin methods and the analytic chemistry methods were used in our studies.Results From the year 1973-1975,in serious endemic areas,fifteen families and one disease outbreak village were investigated,it was found that all patients and his family members had eaten a vast amount of mould millet or maize 4-12 months before onset of the disease; the millet samples collected from endemic areas were cultured and they werc found to be polluted mainly by fungus(20％ of all),the toxin was citreoviridin(CIT).The cause factor of Keshan disease entered into human body through grain but not drinking water,and the transmitting effect was not different with different grains,millet and maize transmit but wheat did not;according to data of endemic disease inspection,after 1990 no new cases of Keshan disease had been reported in the country,at the same time the CIT content in grain produced in endemic areas did not reduced so quickly.However,after 1983,the reform of agriculture promoted significantly the hygienic quality of grain which was considered to be a specific cause for the decreasing of Keshan disease threatening; Keshan disease was distributed on the narrow-long areas from Yunnan till Heilongjiang.These areas were the connection parts,between the cold west north high lands and the warm-moist east-south flatlands,a narrow-long region.The year mean temperature and humidity in endemic areas might be suitable for growing of fungus and production of its toxin ; of animal experiment,rats were feed with CIT contaminated grain every day 4 mg/kg(body weight) for 4-6 weeks,the necrosis of myocardium and cell mitochondria swelling,proliferation and damage were found,just like what had been seen in died cases of Keshan disease.Conclusions The cause of Keshan disease is CIT toxin,the endemic conditions are geographic climate suitable for growing of fungus and production of its toxin and bad hygienic situation of grain storage.Some discussion about the prevention mcthod was proceeding.