Objective To evaluate the accuracy and feasibility of time-resolved immunofluorometric assay (TRI FA) for detection of HBsAg based on Abbott automated chemiluminescence immunoassay(CMIA),so as to carry out this project in primary hospitals,and provide reference for individual antiviral strategy and prediction of therapeutic effect.Methods Serum of 157 patients infected with hepatitis B virus were detected with CMIA and TRIFA,specimens with HBsAg titers exceeding the detection limit were firstly diluted,then performed quantitative analysis.HBsAg levels were divided into 4 groups:≤100 IU/mL,101-1 000 IU/mL,1 001-20 000 IU/mL,and ＞ 20 000 IU/mL,quantitative correlation between two methods was analyzed.Results The linear regression equation of two methods was Y=2.323X-896.3,correlation coefficent r=0.943,P＜0.001.CMIA was as a reference,4 groups were divided for analysis,results showed that when detected specimens was at low concentration of HBsAg,TRIFA value was low compared with CMIA method,while detected specimens was at high concentration of HB sAg,CMIA value was high,two reagents had good consistency in the detection of different concentrations of HBsAg(both P＜0.05),when concentration was at 1 001-20 000 IU/mL,consistency was the best.Conclusion The accuracy of two reagents in the quantitative detection of HBsAg is similar,and the best correlation of detection value is 1 000-20 000 IU/mL.TRIFA assay has wide application for its low-cost and easy to be operated,which is especially suitable for primary hospitals.

Objective: To investigate the epidemiological characteristics and associated factors of scoliosis in primary and secondary school students in Guangdong, and to provide guidance for scoliosis control. Methods: Using a stratified cluster random sampling method, a total of 38 649 students aged 9-18 were selected from 132 primary and secondary schools in the Pearl River Delta and non Pearl River Delta cities for scoliosis screening and related associated factors questionnaire survey from September to October 2020. Results: A total of 1 440 students were detected with scoliosis, with a detection rate of 3.73%. The detection rate of girls was 4.90%, which was higher than that of boys at 2.66%( χ 2=386.89, P <0.01). The detection rate in the Pearl River Delta region was 4.09%, which was higher than the non Pearl River Delta region at 3.38%( χ 2=13.22, P <0.01). The detection rate in urban areas was 4.51%, which was higher than counties at 2.79%( χ 2=78.70, P <0.01). The detection rate increased with the increase of the school period, high school (5.94%)>junior high school (4.50%)>elementary school (1.35%)( χ 2=386.89, P <0.01). Multivariate Logistic regression analysis showed that region, urbanicity, gender, educational stage, exercise, using electronic mobile devices, nutritional status are the influencing factors for scoliosis ( OR=0.41-3.78, P <0.05). Conclusion The detection rate of scoliosis in primary and secondary school students in Guangdong Province varies by gender, urbanicity and educational stages. Female students, as well as junior and senior high school students should be paid more attention.

OBJECTIVE: To determine whether time-resolved immunofluorescence assay (TRIFA) shares the similar accuracy and specificity with automatic chemiluminescence immunoassay (CMIA) in analyzing HBeAg levels in hepatitis B.
 METHODS: A total of 157 serum samples were collected from outpatients with infection of HBV in Xiangya Hospital, Central South University. CMIA and TRIFA were used to analyze HBeAg quantitation and HBeAg/HBeAb qualitative detection, respectively.
 RESULTS: The linear regression equation for the two methods was Y=0.72779X-4.0551 (r=0.712, P<0.001). Compared with the CMIA, the sensitivity and specificity in detection of HBeAg by TRIFA were 89.89% and 100%, respectively, and the coincidence rate of HBeAg was 94.27% by two assays. Similarly, the sensitivity and specificity in detection of HBeAb by TRIFA were 100% and 95.45%, respectively. The coincidence rate was 97.45% by two assays.
 CONCLUSION TRIFA has similar accuracy, sensitivity, and specificity with CMIA in quantitative detection of HBeAg, and their coincidence rate in detection of HBeAg/HBeAb is high.
Feasibility Studies ; Fluorescent Antibody Technique ; Hepatitis B ; Hepatitis B Antibodies ; Hepatitis B e Antigens ; Hepatitis B virus ; Humans

Objective To understand the epidemiological characteristics of the cases of COVID-19 epidemic clusters, and explore the influence of family factors and social factors such as group activities on the spread of the disease. Methods The data of cases of COVID-19 epidemic clusters from 19 January, 2020 to 25 February, 2020 were collected from the official platforms of 36 cities in 6 provinces in China. Descriptive statistical methods, χ 2 test and curve fitting were used to analyze the epidemiological characteristics of the clustered cases. Results By 25 February, 2020, the data of 1 052 cases in 366 epidemic clusters were collected. In these clustered cases, 86.9%(914/1 050) occurred in families. Among the 1 046 cases with gender information, 513 were males (49.0%) and 533 were females (51.0%). The cases were mainly young adults between 18 and 59 years old, accounting for 68.5% (711/1 038). In the 366 epidemic clusters , the clusters in which the first confirmed cases with the history of sojourn in Wuhan or Hubei accounted for 47.0%(172/366). From 19 January to 3 February, 2020, the first confirmed cases with Wuhan or Hubei sojourn history accounted for 66.5%. From 4 to 25 February, the first confirmed cases who had Wuhan or Hubei sojourn history accounted for only 18.2%. The median of interval between the first generation case onset and the second generation case onset was 5 (2-8) days. The median of onset- diagnosis interval of the initial cases was 6 (3-9) days, and the median of onset-diagnosis interval of the secondary cases was 5 (3-8) days. Conclusions Epidemic clusters of COVID-19 were common in many cities outside Wuhan and Hubei. Close contact in family was one of the main causes for the spread of household transmission of the virus. After 4 February, the epidemic clusters were mainly caused by the first generation or second generation cases in local areas, and the time for diagnosis became shorter.