Objective To provide a scientific basis for prevention of Keshan disease by observing the changes of electrocardiogram in residents from Keshan disease area and urban residents in Ju County.Method In 2013,four countries (towns) of Sangyuan,Anzhuang,Qishan and Longshan were selected as the investigation sites across the Keshan disease areas in Ju County of Shandong Province,one village was selected in each country (town),no less than 200 people were chosen from each village.There were 36 residential communities in urban area in Ju County,one residential community was selected from 4 positions (east,west,south and north) in urban area,no less than 200 non-endemic urban residents were chosen from each residential community as control,the electrocardiogram examination was conducted.According to the Keshan Disease Diagnostic Standard (WS/T 210-2011),Keshan disease was diagnosed.Results Among the 964 inhabitants investigated in Keshan disease area,143 cases showed abnormal electrocardiogram and the detection rate was 14.83％;in the 926 cases of urban electrocardiogram,78 cases showed abnormal electrocardiogram,abnormal rate was 8.42％,the difference was statistically significant (x2 =18.80,P ＜ 0.01).There were 93 cases who met the 8 Keshan disease diagnostic criteria of abnormal electrocardiogram changes in the Keshan disease areas,abnormal rate was 9.65％;while there were 37 cases in urban residents,abnormal rate was 4.00％,the difference was statistically significant (x2 =23.55,P ＜ 0.01).Conclusion These residents who have lived in Keshan disease endemic areas have a higher rate of abnormal electrocardiogram in Ju County of Shandong Province,they are still threatened by the causative factors of Keshan disease,and the authority should strengthen the prevention measures of Keshan disease.

Objective To investigate the current situation and relevant factors related to the onset of Keshan disease (KSD) in Ju County of Shandong Province.Methods In 2012,one natural village was selected by means of random number table as the investigating site in Qishan,Anzhuang and Longshan towns,respectively,in KSD endemic areas of Ju County.Permanent residents of all age groups were taken as observation subjects.Then,clinical examination including electrocardiography (ECG) and X-ray for suspected patients was carried out.Fifteen hair samples were collected in every investigating site for detecting selenium content by fluorescence method.At the same time,economic income and per capita share of grain were investigated.Results There were 925 residents investigated in the 3 investigation sites and 27 cases of KSD were found; the total incidence rate was 2.92％.Among the 925 residents investigated,158 cases showed abnormal ECG,and total incidence of abnormal ECG was 17.08％.Among 11 X-ray films,5 cases of cardiac enlargement were found.The selenium content of hair was (0.430 ± 0.062) mg/kg; the average economic income was 9 561 yuan,and the per capita share of grain was 820 kg.Conclusions The incidence rate of KSD in Ju County is low and steady.Keshan disease is controlled in Ju County.