Objective:To establish a practical and systematic pre-deployment base-based training course for medical units in peacekeeping level-II hospitals.Methods:We surveyed the current status of pre-deployment training of medical teams in peacekeeping level-II hospitals, and organized expert discussions to preliminarily construct centralized training course contents. At the same time, the Delphi method was used to conduct two rounds of questionnaire-based consultation to evaluate the overall framework design of the course and the rationality and importance scores of each module. The contents of the pre-deployment training course were further selected and optimized based on the positive coefficient (%), authority coefficient (Cr), coefficient of concordance ( W), and coefficient of variation (Cv). Results:The contents of the pre-deployment training course for the medical units of peacekeeping level-II hospitals were preliminarily established. The experts scored high for the combat onsite first-aid skills module [rationality score, (9.32±0.75) points; importance score, (9.45±0.65) points] and the combat wound treatment module [rationality score, (9.33±0.75) points; importance score, (9.28±0.74) points], and scored lowest for the field survival module [rationality score, (7.95±2.28) points; importance score, (7.87±2.16) points].Conclusions:The established contents of the pre-deployment base-based training course for the medical units of peacekeeping level-II hospitals are reasonable and practical, which lays the foundation for perfecting the pre-deployment training system of peacekeeping medical teams.

Objective:To analyze the changing trend of polio vaccine immunization effectiveness and vaccine titer in Beijing in 2012, 2014, 2016 and 2018 before and after the adjustment of polio vaccine immunization program strategy.Methods:According to the convenient sampling method,the vaccination clinics of Chaoyang and Yanqing Districts in 2012, Fengtai and Daxing Districts in 2014, Tongzhou and Pinggu Districts in 2016, Dongcheng and Shunyi Districts in 2018 were selected as monitoring points. A total of 292 children were selected 4-8 weeks after the completion of 3 doses polio vaccine basic immunization which were 3 doses of trivalent oral poliovirus vaccine（tOPV）schedule before the strategy adjustment in 2012-2014 and 1 dose of inactivated poliovirus vaccine (IPV) following 2 doses of bivalent oral poliovirus vaccine (bOPV) sequential schedule after the adjustment in 2016-2018. About 1.0 ml blood samples were collected to detect type Ⅰ and Ⅲ neutralizing poliovirus antibody. A total of 9 oral poliovirus vaccines (8 vaccines in 2012) were selected from different sources of vaccine storage every year to test the vaccine titer using random number method .Results:The [ M（ P25， P75）] age of 292 children was 5 (5, 6) months, and the ratio of male to female was 1.04 (149/143). In 2012, 2014, 2016 and 2018, 66,72,68 and 86 children were investigated respectively. After basic immunization, antibody positive rates for type Ⅰ and Ⅲ poliovirus were 100%, except 98.61% (71) for type Ⅰ poliovirus in 2014. The neutralizing antibody titer of type Ⅰ and Ⅲ poliovirus was higher in 2016 and 2018 than that in 2012 and 2014 ( P<0.001). The average titer of tOPV were (6.05±0.15) and (6.16±0.12) lgCCID 50 per dose in 2012 and 2014. The average titer of bOPV were (6.88±0.21) and (6.26±0.14) lgCCID 50 per 100 μl in 2016 and 2018 ( P<0.001). Conclusion:Before and after the adjustment of polio vaccine immunization strategy in Beijing, the basic immunization success rate of the IPV-bOPV sequential immunization schedule was good as well as full tOPV schedule. The level of polio antibody produced by the IPV-bOPV sequential immunization schedule was higher. After adjustment, bOPV titer in 2016 was significantly higher than those before adjustment, while bOPV titer decreased significantly in 2018.

Objective:To analyze the changing trend of polio vaccine immunization effectiveness and vaccine titer in Beijing in 2012, 2014, 2016 and 2018 before and after the adjustment of polio vaccine immunization program strategy.Methods:According to the convenient sampling method,the vaccination clinics of Chaoyang and Yanqing Districts in 2012, Fengtai and Daxing Districts in 2014, Tongzhou and Pinggu Districts in 2016, Dongcheng and Shunyi Districts in 2018 were selected as monitoring points. A total of 292 children were selected 4-8 weeks after the completion of 3 doses polio vaccine basic immunization which were 3 doses of trivalent oral poliovirus vaccine（tOPV）schedule before the strategy adjustment in 2012-2014 and 1 dose of inactivated poliovirus vaccine (IPV) following 2 doses of bivalent oral poliovirus vaccine (bOPV) sequential schedule after the adjustment in 2016-2018. About 1.0 ml blood samples were collected to detect type Ⅰ and Ⅲ neutralizing poliovirus antibody. A total of 9 oral poliovirus vaccines (8 vaccines in 2012) were selected from different sources of vaccine storage every year to test the vaccine titer using random number method .Results:The [ M（ P25， P75）] age of 292 children was 5 (5, 6) months, and the ratio of male to female was 1.04 (149/143). In 2012, 2014, 2016 and 2018, 66,72,68 and 86 children were investigated respectively. After basic immunization, antibody positive rates for type Ⅰ and Ⅲ poliovirus were 100%, except 98.61% (71) for type Ⅰ poliovirus in 2014. The neutralizing antibody titer of type Ⅰ and Ⅲ poliovirus was higher in 2016 and 2018 than that in 2012 and 2014 ( P<0.001). The average titer of tOPV were (6.05±0.15) and (6.16±0.12) lgCCID 50 per dose in 2012 and 2014. The average titer of bOPV were (6.88±0.21) and (6.26±0.14) lgCCID 50 per 100 μl in 2016 and 2018 ( P<0.001). Conclusion:Before and after the adjustment of polio vaccine immunization strategy in Beijing, the basic immunization success rate of the IPV-bOPV sequential immunization schedule was good as well as full tOPV schedule. The level of polio antibody produced by the IPV-bOPV sequential immunization schedule was higher. After adjustment, bOPV titer in 2016 was significantly higher than those before adjustment, while bOPV titer decreased significantly in 2018.

Objective To determine the oral health， related knowledge and behavior of 12-year-old children in Guoluo Prefecture， Qinghai Province， and provide scientific evidence for policy-making of oral health programs. Methods Six counties were selected by using a multi-stage and stratified sampling strategy. Oral health examination and survey questionnaire were performed according to the instructions of the Fourth National Oral Epidemiology Study. The oral health examination included dental caries and periodontal status. The questionnaire investigated oral health knowledge and behavior. Results The prevalence of caries was 71.6% （288/402）and their DMFT was 2.04±1.90. Approximately 1.2% of deciduous teeth were filled. In the children， 81.3% （327/402） had teeth brush every day， while only 42.0% （169/402） brushed twice or more per day. Moreover， 10.2% （41/402） used fluoride toothpaste； in contrast， 62.2% （250/402） did not use toothpaste appropriately. In addition， the survey on dietary habits showed that 41.3% of the children consumed sweetened food once or more per day. Conclusion Oral health education should be further strengthened to promote oral health in children.

Objective    To analyze the influencing factors for re-positive nucleic acid test in discharged corona-virus disease 2019 (COVID-19) patients in Chengdu, Sichuan Province, and to provide data support for the epidemics prevention and control. Methods    The clinical data of 660 discharged COVID-19 patients from January 23, 2020 to February 28, 2021 in our center were retrospectively analyzed. The patients were divided into two groups according to the reexamination of virus nucleic acid, including a negative group [549 patients, including 428 males and 121 females with a median age of 33.0 (28.0, 48.0) years] and a positive group [111 patients, including 76 males and 35 females with a median age of 39.0 (28.0, 51.0) years]. The clinical data of the two groups were compared. Results     The re-positive rate of the discharged patients was 16.82%. Univariate analysis showed that the re-positive rate of females was higher than that of males (χ2=4.608, P=0.032). The re-positive rate of confirmed patients was higher than that of asymptomatic infected patients (χ2=8.140, P=0.004). The re-positive rate of domestic patients was higher than that of imported patients (χ2=9.178, P=0.002). The counts of CD3+ (P=0.038), CD4+ (P=0.048) and CD8+ (P=0.040) T lymphocytes in the negative group were higher than those in the positive group. The binary logistic regression analysis showed that the clinical classification and CD8+ T lymphocyte count were independent risk factors affecting the recurrence of virility. Conclusion    The gender, origin, T lymphocyte subsets count and clinical type are the influencing factors for re-positive result, and clinical type and CD8+ T lymphocyte count are the independent influencing factors for re-positive result. Therefore, improving the immunity of infected patients, as well as early detection and timely treatment are effective means to reduce the re-positive occurrence.