[Analysis of antibodies of poliviruses in persistent populations in Beijing, 2012].

OBJECTIVE: To analyze the polio immunity level of persistent population in Beijing, 2012. METHODS: A total of 1 676 subjects residing more than 6 months in Beijing were selected by stratified random cluster sampling design in 2012. Demographic characteristics, history of oral poliovirus vaccine (OPV) immunization were investigated by questionnaire. All 5 ml blood sample were collected for testing of polio neutralizing antibody using the method of microcell neutralization. The positive rate and the geometric mean titer (GMT) of polio neutralizing antibody type I, II and III were analyzed in different groups. RESULTS: The positive rate of type I, II and III were 98.2% (1 645/1 676), 98.1% (1 644/1 676), 97.6% (1 635/1 676); The GMT were 1:130.2, 1: 113.4 and 1: 79.7. Three types of positive rates in<15 years group (99.7% (664/666), 99.8% (665/666), 99.5% (663/666)) were higher than those of ≥ 15 years group (97.1% (981/1 010), 96.9% (979/1 010), 96.2% (972/1 010)), the differences were significant (all the values of P < 0.01); The GMT in<15 years group (1:325.9, 1:250.5, 1:190.7) were higher than that of ≥ 15 years group (1: 71.1, 1: 67.2, 1: 44.8), the difference was significant (all the values of P < 0.01). The positive rate (99.0%-100%) and GMT (1: 128.8-1: 300.7) in vaccination information confirmed population were higher. The highest positive rate (all were 100%) and GMT(1: 409.7-1: 636.7) were observed in children who vaccinated three times. CONCLUSION: The polio antibody of healthy population was at a high level in Beijing in 2012; Especially the age groups of < 15 years which were covered by vaccines.Immunization barrier had been formed firmly to interrupt the transmission of wild poliovirus and vaccine-derived poliovirus.

[Analysis of measles immunity level in persistent populations in Beijing, 2012].

OBJECTIVE: To analyze the measles immunity level of persistent population in Beijing. METHODS: A total of 2125 objects from 10 age groups, who had been living in Beijing for over 6 months, were selected from urban and rural areas in Beijing in 2012. Demographic characteristics, history of measles and vaccine immunization were investigated by questionnaire. 5 ml blood sample of each subject was collected, and the Measles IgG antibody was measured by ELISA assay. RESULTS: Positive rate of measles antibody was 84.71% (1800/2125) and standardized positive rate was 88.07% . Median of antibody was 960.46 IU/L. Positive rate and median of measles antibody were significantly different between population from different age groups (χ(2) = 341.60, P < 0.01; H = 216.27, P < 0.01). Antibody positive rate and median were lowest in the <1 year age group, which were separately 43.06% (90/209) and 185.80 IU/L; and highest in the 1-4 (97.31% (181/186) and 2448.81 IU/L) and 5-9 years age group (96.46% (218/226) and 1910.72 IU/L). The range of antibody positive rate and median in adults of ≥ 15 years were 81.98%-90.14% and 744.38-1474.84 IU/L. Antibody positive rate and median in persistent population, which were separately 82.45% (883/1071) and 899.82 IU/L, were lower than those in migrant population, which were 87.00% (917/1054) and 166.19 IU/L, respectively (χ(2) = 8.51, P < 0.01;U = 538 704.00, P < 0.01). Antibody positive rate and median in population with vaccination history, which were separately 91.95% (891/969) and 1443.11 IU/L, were higher than those population without vaccination history and people whose history unknown (32.95% (57/173) , 127.33 IU/L; 86.67% (852/983) , 923.73 IU/L). The difference showed statistical significance (χ(2) = 399.92, P < 0.01; H = 202.11, P < 0.01). CONCLUSION: Among the persistent population in China, measles antibody level among the children aging 1-9 years old was high enough to prevent outbreak and epidemic of measles. However, we should try our best to strengthen the measles antibody level among the babies younger than 1 year old and the migrant population aging between 15 and 40 years old.

Impact of herpes zoster and post-herpetic neuralgia on health-related quality of life in Miyun District of Beijing, China: An EQ-5D survey.

Background: Herpes zoster (HZ) and post-herpetic neuralgia (PHN) cause considerable morbidity, especially in elderly adults, but the burden is under-recognized in mainland China. Methods: We conducted a case registry and follow-up study of HZ in Miyun District, Beijing from January 1, 2017 through December 31, 2018. Registered HZ cases were followed-up for pain to 365 days. The first 50 patients with HZ in each age group (≤14, 15-29, 30-39, 40-49, 50-59, 60- 69, 70-79, ≥80 years) and all those with PHN completed the EuroQoL five dimensions questionnaire (EQ-5D) to evaluate health-related quality of life (HRQoL) in patients with HZ and PHN. Ratings using the EQ-5D dimensions, visual analogue scale (VAS), health utility score (HUS) and quality-adjusted life years (QALYs) lost were compared among age groups. Results: In total, 2008 patients with HZ were followed for a median 22 days (interquartile range[IQR] = 20-90), with an estimated incidence of 4.39 per 1000 person-years. We identified 122 (6.08 %) PHN cases. The median age of patients with PHN (65 years, IQR = 55-71) was older than that of patients with HZ (54 years, IQR = 43-64) (P < 0.001). The median duration of pain was 170 days (IQR = 144-355.5) for PHN and 15 days (IQR = 9-25) for HZ. All 95 patients with PHN and 319 sampled patients with HZ completed the EQ-5D survey. The median QALY loss of HZ increased from 0.004 (IQR = 0.001-0.02) in patients 50-59 years old to 0.02 (IQR = 0.01-0.06) in those ≥ 80 years old (P < 0.01). After weighting for age, the mean QALY loss per HZ case was estimated at 0.02 (standard deviation [SD] 0.04). The mean QALY loss per PHN case was 0.13 years (SD 0.12). Conclusions: HZ and PHN caused a substantial burden, especially among adults aged ≥ 50 years in Miyun District, Beijing, China. Vaccination should be considered to alleviate the burden of this painful disease.

Rapid and nondestructive determination of sorghum purity combined with deep forest and near-infrared hyperspectral imaging.

This study combined hyperspectral imaging (HSI) and deep forest (DF) to develop a reliable model for conducting a rapid and nondestructive determination of sorghum purity. Isolated forest (IF) algorithm and principal component analysis (PCA) were used to remove the abnormal data of sorghum grains. Competitive adaptive reweighted sampling (CARS) algorithm and successive projections algorithm (SPA) were combined and used to extract the characteristic wavelengths. Gray-level co-occurrence matrix (GLCM) was used to extract the textural features. DF models were established based on the different types of data. Specifically, the DF models established using the characteristic spectra produced the best recognition results: the average correct recognition rate (CRR) of the models was greater than 91%. In addition, the average CRR of validation set Ⅰ was 88.89%. These results show that a combination of HSI and DF could be used for the rapid and nondestructive determination of sorghum purity.

Perception of the COVID-19 Epidemic and Acceptance of Vaccination Among Healthcare Workers Prior to Vaccine Licensure - Beijing Municipality, China, May-July 2020.

What is already known about this topic? The coronavirus disease 2019 (COVID-19) vaccine development has been progressing, but acceptance of the new vaccines by healthcare workers (HCWs) was not well known prior to approval of COVID-19 vaccines in China. What is added by this report? This study found that before vaccine approval, Beijing HCWs expressed moderate willingness to get vaccinated. Factors positively influencing willingness included free vaccination and belief that the vaccine had been fully evaluated. A negatively influencing factor was presence of an underlying disease. Trust in vaccines, in general, was positively associated with willingness to get new vaccines. What are the implications for public health practice? COVID-19 vaccines should be provided at no cost to HCWs. Effective measures should be taken to enhance the acceptance of COVID-19 vaccination among HCWs in China.

[Effectiveness on post-exposure vaccination of varicella and its influencing factors in elementary schools in Beijing].

OBJECTIVE: To evaluate the effectiveness of post-exposure varicella vaccination in elementary schools in Beijing and to explore its influencing factors. METHODS: From May to July 2007, varicella cases from 49 elementary schools in 4 districts in Beijing were observed prospectively. The study included 7882 children who were from the same classrooms, same floor or same bungalow areas with the varicella cases. Vaccination status, history on varicella and onset of rashes were collected to calculate the secondary attack rate among those children under observation and then the effectiveness of vaccine was calculated. RESULTS: The protection rate on post-exposure vaccination among children under observation was 85.26%. The rates were higher when the 1st case had received varicella vaccine before the onset, vaccines were administered soon after the exposure or there were less varicella cases occurred in the schools. For children in the same class, same floor or bungalow with varicella cases before post-exposure vaccination, the average rates of protection by vaccination were 84.26% and 87.06%, respectively. When the 1st case had received varicella vaccine prior to the onset, the post-exposure protection rates reached 92.09% and 93.06%, respectively, higher than that of the case when the 1st case had received no vaccination. When the administration of vaccine right after the occurrence of first varicella case, the rates of the effectiveness of vaccine were 83.09% and 93.02%, both of which were higher than that of vaccine administered after the occurrence of 2 or 3 cases. When the vaccine administration of vaccination combined with the isolation of the already infected cases or within 5 days after the onset of the 1st case, the vaccine effectiveness could reach 86.60% and 92.73%, both were higher than otherwise. However, in those schools that bungalows were used as classrooms but without bus, canteen from school or student lodgings, it seemed that post exposure vaccination was more effective in preventing varicella from occurring. CONCLUSION: Varicella vaccination after exposure in elementary schools in Beijing was effective in prevention and control of the disease. Immediate administration together with the isolation of cases could maximize the effectiveness of the vaccine.