[Research and application of the SARS-CoV-2 vaccine based on adenovirus vector technology platform].

During the global efforts to prevent and control the COVID-19 pandemic, extensive research and development of SARS-CoV-2 vaccines using various technical approaches have taken place. Among these, vaccines based on adenovirus vector have gained substantial knowledge and experience in effectively combating potential emerging infectious diseases, while also providing novel ideas and methodologies for vaccine research and development (R&D). This comprehensive review focuses on the adenovirus vector technology platform in vaccine R&D, emphasizing the importance of mucosal immunity induced by adenoviral vector-based vaccine for COVID-19 prevention. Furthermore, it analyzes the key technical challenges and obstacles encountered in the development of vaccines based on the adenovirus vector technology platform, with the aim of providing valuable insights and references for researchers and professionals in related fields.

[Analysis of the vaccination status of enterovirus type 71 inactivated vaccine in China from 2017 to 2021].

Objective: To understand the vaccination status of enterovirus type 71 (EV71) inactivated vaccines in China from 2017 to 2021 and provide evidence for making policy on immunization strategy against hand, foot and mouth disease (HFMD). Methods: Using the reported dose number of EV71 vaccination and birth cohort population data collected by the China immunizaiton program information system to estimate the cumulative coverage of EV71 vaccine by the end of 2021 among the birth cohorts since 2012 at national, provincial, and prefecture levels, and analyze the correlation between the vaccination coverage and the potential influencing factors. Results: As of 2021, the estimated cumulative vaccination coverage of the EV71 vaccine was 24.96% in birth cohorts since 2012. The cumulative vaccination coverage was between 3.09% and 56.59% in different provinces, between 0 and 88.17% in different prefectures. There was a statistically significant correlation between vaccination coverage in different regions and the region's previous HFMD prevalence and disposable income per capita. Conclusions: Since 2017, the EV71 vaccines have been widely used nationwide, but the coverage of EV71 vaccination varies greatly among regions. Vaccination coverage is higher in relatively developed regions, and the intensity of previous epidemic of HFMD may have a certain impact on the acceptance of the vaccine and the pattern of immunization service. The impact of EV71 vaccination on the epidemic of HFMD requires further studies.

[Challenges to global pertussis prevention and control].

Pertussis is an acute, highly infectious respiratory disease caused by Bordetella pertussis, and is one of the leading causes of infant disease and death worldwide. The pertussis vaccine has been used in the expanded program on immunization globally since 1974 and the vaccination coverage remains high. In recent years, the pertussis incidence rate increased, even pertussis outbreaks occurred, in more and more countries or areas after years with low incidence level. The disease burden of pertussis has been seriously underestimated, and the prevention and control of pertussis is facing many challenges. This article reviews the epidemic status of pertussis worldwide, the factors affecting the reemergence of pertussis, and the challenges in the prevention and control to provide a reference for prevention and control of pertussis.

[Considerations for the development of adult vaccination in China].

Adult vaccination is an important component of the life-course immunization for all. Strengthening adult vaccination in China contributes to shrinking immunization gaps between regions and groups, enhancing the overall immunity of our population, and promoting health equity and social prosperity. Chinese adults bear the heavy burden of vaccine preventable diseases such as influenza, pneumococcal diseases and shingles, and have low coverage of vaccines against those diseases, so it is necessary to make efforts to improve adult vaccination development. This article focuses on elaborating the values of adult vaccination, introducing the current status of adult vaccination abroad, and analyzing the challenges and existing foundations for China to provide adult vaccination, and makes suggestions for the building and development of adult vaccination.

[Analysis for dropout of DTaP routine immunization in China in 2019].

Objective: To analyze the dropout of adsorbed diphtheria, tetanus and acellular pertussis combined vaccine (DTaP) routine immunization in China in 2019. Methods: DTaP vaccination data in all counties in China were collected through National Immunization Program Information Management System in 2019. Cumulative dropout rate and vaccination rate of DTaP in different provinces were calculated. According to the P25, P50 and P75 values of DTaP dropout rate for all counties by province, counties in each province were divided into four groups (Q1-Q4). The DTaP average dropout rate of four groups and absolute difference (difference in DTaP average dropout rate between Q4 and Q1) were calculated. Spearman rank correlation was used to analyze the relationship between absolute difference and provincial DTaP dropout rate, DTaP1 and DTaP3 vaccination rate. Results: DTaP1 vaccination rate ranged from 92.98% to 99.94% by province, with a median of 99.55%. Provincial DTaP dropout rate ranged from 0.36% to 28.66%, with a median of 3.54%. The provincial DTaP dropout rate was more than 10% in Gansu and Guizhou, about 28.66% and 17.19%. Absolute difference ranged from 4.02% to 39.22%, with a median of 10.16%. Provinces with the largest absolute difference were Gansu, Qinghai, Liaoning and Guizhou, about 39.22%, 34.48%, 23.31% and 21.33%, respectively. Correlation analysis indicated that the absolute difference was positively correlated with provincial DTaP dropout rate, with a correlation coefficient of 0.492 (P=0.004). It was negatively correlated with DTaP1 and DTaP3 vaccination rate. Correlation coefficients were -0.542 (P=0.001) and -0.562 (P=0.001), respectively. Conclusions: There are significant county-level differences in DTap dropout rate in most provinces, with relatively high difference in western provinces.

[Quality of life and risk factors in patients with herpes zoster].

Objective: To evaluate the quality of life and influencing factors of patients with herpes zoster (HZ) seen in hospitals. Methods: Based on Zoster Brief Pain Inventory (ZBPI) and Five-level EuroQol Five-dimensional Questionnaire (EQ-5D-5L), a cross-sectional survey was conducted to evaluate the pain severity and quality of life of 332 HZ cases seen in 22 hospitals of Lu'an City (Anhui Province), Zibo City (Shandong Province) and Tongchuan City (Shaanxi Province) from October to December 2021. The censored least absolute deviations (CLAD) model was used to analyze the related factors affecting the changes of patients' health utility values. Results: The 45.5% of 332 HZ cases were male. The median (Q1,Q3) age was 59 (50, 68) years. 59.64% of them assessed by ZBPI had moderate to severe pain in the past 24 hours (worst pain score≥5), and that of PHN cases was 84.8%(39/46). 77.7% (258/332), 77.4% (257/332) and 74.1% (246/332) of all patients reported that pain interfered with sleep, mood and general activities, respectively. Aging [ß40-49y (95%CI)=-0.11 (-0.15, -0.08); ß50-59y (95%CI)=-0.03 (-0.05, 0.00); ß60-69y (95%CI)=-0.09 (-0.12, -0.06); ß70-90y(95%CI)=-0.16 (-0.19, -0.12)], working status (unemployed) [ßfarmer (95%CI)=0.15 (0.13, 0.18); ßretirees(95%CI)=0.21 (0.18, 0.24); ßemployee (95%CI)=0.13 (0.10, 0.16) ], complications[ßPHN (95%CI)=-0.08 (-0.13, -0.04); ßother complications (95%CI)=-0.12 (-0.15, -0.08)], within 30 days after onset [ß(95%CI)=-0.01 (-0.03, 0.01)] and treatment [ßother complications (95%CI)=-0.09 (-0.11, -0.06)] were related factors for the decline of health utility value (all P values <0.05). Conclusions: More than half of the patients with HZ had moderate to severe pain in the past 24 hours, which had a serious negative impact on the physical and mental health of the patients. Elderly patients, acute patients and patients with complications had lower health utility values and worse health status. We suggest that eligible people be vaccinated with HZ vaccine as soon as possible.

[Epidemiological distribution of hepatitis B virus genotypes in acute hepatitis B cases in China,2015-2017].

Objective: To analyze the genotype distribution of acute hepatitis B virus in China. Methods: A total of six hundred and twenty acute Hepatitis B cases reported to China Information System for Diseases Control and Prevention from 2015 to 2017 were selected. First, the full-length HBV genome was obtained by nested PCR amplification. In addition, the HBV genotype was determined by constructing a phylogeny tree. Finally, using primarydata, HBV genotype distribution was analyzed. Results: A total of 519 (83.71%, 519/620) sequences were obtained genotype of 620 acute hepatitis B cases, including A (0.19%, 1/519), B (27.17%, 141/519), C (62.04%, 322/519), D (9.06%, 47/519), I (0.77%, 4/519) and C/D (0.77%, 4/519); B2(95.03%, 134/141) and C2 (72.67%, 234/322) were the two major subgenotypes. Genotypes were distributed differently in seven regions of China. The proportion of genotype C appeared higher in Northeast China (94.55%, 52/55), North China (93.85%, 61/65), East China (78.87%, 56/71), and South China (58.14%, 50/86). The proportion of genotype B was higher in Central China (58.07%, 36/62) and Southwest China (52.94%, 45/85), the proportion of genotype D was the highest in Northwest China (48.42%, 46/95). A total of 515 cases were classified as serotypes, including 'adr' (57.48%, 296/515), 'adw' (30.87%, 159/515), 'ayr' (0.19%, 1/515), and 'ayw' (11.46%, 59/515). Genotype B was dominated by 'adw' serotype (92.14%, 129/140), genotype C was dominated by 'adr' serotype (91.88%, 294/320),all genotype D were 'ayw' serotype. The genotype of acute hepatitis B was correlated with serotype, 'adw' was dominant in genotype B, 'adr' was dominant in genotype C and 'ayw' was dominant in genotype D.In different gender and age group, there was no statistical significance ingenotype distribution (P>0.05). Conclusions: The genotype of acute hepatitis B in China from 2015 to 2017 was mainly B, C, and D; genotype C was dominant in the Northeast China,North China, East China and South China; B and C were common in Central and Southwest China, and genotype B was dominant. Genotype D was primarily distributed in Northwest China. The genotype of acute hepatitis B was correlated with serotype, 'adw' was dominant in genotype B, 'adr' was dominant in genotype C and 'ayw' was dominant in genotype D. There was no difference in the distribution of acute hepatitis B genotypes among different genders and age groups.

[Self-awareness rate and its influencing factors of their infection status among hepatitis B surface antigen-positive persons aged 15-69 years in China].

Objectives: To understand the awareness rate and its influencing factors of their HBV infection status among HBsAg-positive persons aged 15-69 years in China. Methods: A cross-sectional design was used to conduct a questionnaire survey on the awareness of their infection status among HBsAg-positive persons aged 15-69 years who were identified in the 2020 national hepatitis B seroepidemiology survey. The awareness rate of the whole respondent and respondents with different characteristics were described, and the differences were compared with the χ2 test. The logistic regression model was used to analyze the factors influencing the awareness rate. Results: The overall awareness rate among the respondents was 43.10% (1 828/4 241). The awareness rate was lower in males than in females (41.30% vs. 44.65%). The awareness rate was lower in the 60-69-years-old age group than in other age groups (30.38% vs. 36.77%-57.58%). The awareness rate was lower in rural areas than in urban areas (39.43% vs. 47.32%). The awareness rate was lower in regions with a per capita gross domestic product (GDP) below RMB 54 000 than in regions with a per capita GDP of RMB 54 000 and above (36.81% vs. 41.61%-50.30%). The awareness rate was lower in respondents without other liver diseases than with other liver diseases (41.52% vs. 60.68%). The awareness rate was lower in respondents without a family history of hepatitis B-related disease or unknown family history than with a family history (43.58% vs. 68.26%; 24.71% vs. 68.26%). Multivariate logistic regression analysis showed that male [odds ratio (OR)=0.841, 95% confidence interval (CI): 0.734-0.964], high school and below [primary school and below, junior middle school, high school/technical secondary school, OR (95%CI): 0.247 (0.190-0.321), 0.451 (0.352-0.577), 0.634 (0.486-0.827)], rural areas (OR=0.822, 95%CI: 0.715-0.945) and regions with a per capita GDP below RMB 80 000 [54 000-80 000, OR (95%CI): 0.810 (0.688-0.954), below RMB 54 000, OR (95%CI): 0.793 (0.669-0.941)] were the negative factors influencing the awareness rate. While 30-39-years-old (OR=2.089, 95%CI: 1.626-2.683) and 40-49-years-old (OR=1.590, 95%CI: 1.250-2.023) age groups, with other liver diseases (OR=2.244, 95%CI: 1.754-2.871) and family history related to hepatitis B (OR=2.688, 95%CI: 2.242-3.223) were the positive factors influencing the awareness rate. Conclusion: The overall awareness rate of their infection status among HBsAg-positive persons aged 15-69 years is 43.10% in China. Health promotion and coverage expansion on HBV screening should be further strengthened to achieve the proposed World Health Organization's target of 90% HBV infection diagnosis rate by 2030.

[Considerations on vaccines and immunization against COVID-19 for epidemic control in China].

The Delta variant of the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has caused a new global wave of the Coronavirus Disease 2019 (COVID-19) pandemic. COVID-19 vaccines currently available in China show high effectiveness against severe illness and death. However, transmission of the virus is not fully stopped by vaccination alone, therefore, integrated vaccination and non-pharmacological interventions is necessary to prevent and control the epidemic in the near future. Further expanded vaccine coverage of primary doses as well as booster shots in China's domestic population are needed to reduce severe illness and death. In order to provide evidence necessary for adjusting and optimizing immunization strategies and pandemic control measures, it is essential to conduct research on vaccine effectiveness against emerging variants, persistence of vaccine-induced protection, surveillance of adverse event following immunization with large-scale vaccine use, and modelling studies on strategic combinations of vaccination and non-pharmacological interventions.

[Impact of additional time spent for vaccination services on overall satisfaction rate in parents].

Objective: To understand the overall satisfaction rate with vaccination services in parents of children, and the impact of additional time consumed for vaccination service on overall satisfaction rate. Methods: From December 2019 to January 2020, a total of 3 178 parents of 0-3 years old children were investigated to collect the information about their basic characteristics, additional time spent for vaccination service and overall satisfaction through questionnaires. Binary logistic regression model and restricted cubic spline model were used to evaluate the impact of additional time spend on the overall satisfaction rate. Results: The overall satisfaction rate of parents with vaccination services was 92.32%. The median time for parents to move from home to vaccination clinic was 10.00 (10.00, 20.00) minutes, the median waiting time to make an appointment was 10.00 (5.00, 15.00) minutes, the median waiting time for vaccination was 5.00 (3.00, 10.00) minutes, and the median total additional time spent was 30.00 (20.00, 45.00) minutes. The binary logistic regression analysis showed that after adjusting the relevant factors, the main factors affecting the overall satisfaction rate were the waiting time for making an appointment (the 4- minutes group vs. 8- minutes group: OR=1.863, 95%CI: 1.307-2.657), waiting time for vaccination (the <4 minutes group vs. 8- minutes group: OR=1.529, 95%CI: 1.102-2.120; the 4- minutes group vs. 8- minutes group: OR=1.534, 95%CI: 1.104-2.130), total additional time spent (the 15- minutes group vs. 30- minutes group: OR=1.470, 95%CI: 1.094-1.976). Restricted cubic spline analysis showed that the waiting time for making an appointment (non-linear: χ2=13.18, P=0.001), the waiting time for vaccination (non-linear: χ2=13.50, P=0.001), and the total additional time consumed (non-linear: χ2=9.38, P=0.009) showed a non-linear inverted "V" dose response relationship to the overall satisfaction of vaccination services. Conclusions: The waiting time for parents to make an appointment, the waiting time for vaccination and the total additional time spent for receiving vaccination services affected the overall satisfaction rate of the vaccination services. And the waiting time for making an appointment was the most important factor, and it is necessary to shorten the waiting time for appointment. It is suggested that the vaccination clinic should make use of information technology (such as WeChat public account, APP) to make accurate appointments, make appointments to the time period to control the number of people within time period.

[Analysis of the time for observation and related factors at clinics after vaccination among children's parents].

Objective: To understand the time for observation and related factors in the clinics after vaccination among children's parents. Methods: From December 2019 to January 2020, parents of children aged 0-3 years were recruited by multiple-stage sampling from 34 vaccination clinics in 12 districts and counties in 6 provinces (Shandong, Guangdong, Henan, Sichuan, Inner Mongolia, and Liaoning). A questionnaire survey on the time of observation after vaccination was conducted. A multivariate logistic regression model was used to analyze the related factors of parental observation time after vaccination. Results: A total of 3 292 parents of 0-3 year's old children were selected, and 3 178 parents were finally included in the analysis. 87.85%(2 792/3 178) of the parents reported that the observation time after vaccination at clinics was ≥30 minutes. Multivariate logistic regression analysis showed that, after adjusting for the regions, the main factors affecting the observation time at clinics after vaccination among parents appeared as observation time informed by physicians at the clinic appeared ≥30 minutes (OR=31.622, 95%CI: 19.847-50.384), parents were medical personnel (OR=2.779, 95%CI: 1.505-5.133), parents being volunteers working on vaccination-related publicity and education activities (OR=1.986, 95%CI: 1.438-2.743), parents aged 35 years old or above (OR=1.900, 95%CI: 1.215-2.971), being parents of the first child (OR=1.663, 95%CI: 1.282-2.156), per capita annual income of the family as 8 000- Yuan (OR=1.646, 95%CI: 1.168-2.319), children aged 0-12 months old (OR=1.646, 95%CI: 1.203-2.252) or 13-24 months old (OR=1.506, 95%CI: 1.064-2.133), obedient to physicians' advice at the clinic (OR=1.481, 95%CI: 1.067-2.055). Conclusions: The proportions of parents observed for ≥30 minutes at the clinics of vaccination were high. When the information was from the physicians at the vaccination clinic, the observation time was the most critical factor for parents to observe at clinics as required.

[Estimation of incidence of viral hepatitis B and analysis on case characteristics in China,2013-2020].

Objective: To understand the epidemiological characteristics of hepatitis B in China, evaluate the performance of elimination hepatitis B in China and provide scientific evidence for the prevention and control of hepatitis B. Methods: An analysis was conducted by using the data of hepatitis B cases reported to the National Notifiable Disease Reporting System (NNDRS) from the areas with low, moderate and high hepatitis B prevalence in China from 2013 to 2020, and the information about the diagnoses of the hepatitis B cases were collected, the incidence of hepatitis B was estimated according to the reporting and diagnosis information and the characteristics of acute and chronic hepatitis B were compared. Results: A total of 27 013 hepatitis B cases were reported to NNDRS, including 4 070 acute cases, 21 971 chronic cases and 972 unclassified cases. Among the reported acute hepatitis B cases, 69.9% (2 845/4 070) were confirmed. Among the reported chronic hepatitis B cases, 89.0% (19 548/21 971) were confirmed, and 2.1% (452/21 971) were confirmed as acute cases. It was estimated that the incidence of acute hepatitis B was 4.6/100 000 and the incidence of chronic hepatitis B cases was 54.5/100 000. The case number of acute hepatitis B in age group 31-45 years was highest, accounting for 35.3% (1 164/3 297). The case number of acute hepatitis B in children under 15 years old was lowest, accounting for 0.4% (13/3 297). The case number of chronic hepatitis B in age group 46-60 years was highest, accounting for 34.4% (7 211/20 932). Conclusions: The incidence of acute hepatitis B was in decrease and the incidence of chronic of hepatitis B was in increase in China year by year. It is important to strengthen the standardized diagnosis and treatment of chronic hepatitis B to decrease the morbidity and mortality of hepatitis B. At the same time, it is necessary to standardize the management and reporting of hepatitis B cases reported to NNDRS to improve the accuracy of the reporting of hepatitis B.

[Cost-benefit analysis of the hepatitis B vaccination to prevent mother-to-child transmission strategies in China, 1992-2019].

Objective: To make a cost-benefit analysis of the hepatitis B vaccination (HepB) to prevent mother-to-child transmission (PMTCT) strategies in China, 1992-2019. Methods: We built a decision analytic-Markov model to estimate the birth cohorts of 1992-2019. The parameters in our model were referred from literature, published yearbooks, and data from Chinese Center for Disease Control and Prevention. We conducted a univariate sensitivity analysis to test the robustness of the model. Results: For the 28 birth cohorts, the Chinese government has invested 37.43 billion RMB Yuan in direct costs and 47.61 billion RMB Yuan in societal costs on HepB vaccination and HBV prevention of mother to child transmission (PMTCT). And we estimated that about 50 million chronic HBV infections and 12.5 million premature deaths due to HBV-related diseases would be averted. China would save 2.89 trillion RMB Yuan and 6.92 trillion RMB Yuan for the direct and societal medical burden on HBV-related conditions. The direct and societal net benefit was 2.85 trillion RMB yuan 6.87 trillion RMB yuan, respectively. The direct and societal benefit-cost ratios (BCRs) were 77.21 and 145.29, respectively. Conclusion: The strategies of HepB vaccination for HBV PMTCT prevention were cost-effective in China during 1992-2019.

[Analysis on hepatitis B cases reported from surveillance points in China, 2019].

Objective: To understand the characteristics of hepatitis B cases reported through the National Notifiable Disease Reported System (NNDRS) of China in 2019, analyze the quality of hepatitis B reporting. Methods: The survey forms and reporting cards of hepatitis B cases in 200 surveillance points in China in 2019 were collected from NNDRS, the completeness rate of the reporting card was calculated, and the reported hepatitis B cases were verified based on the diagnostic criteria (WS 299-2008). The clinical types of the cases after verification were compared with the reported ones, the consistency was evaluated with Kappa test. The reasons for the inconsistent clinical types of the cases were analyzed. Results: In 2019, a total of 64 686 hepatitis B cases were reported through NNDRS. Acute, chronic and unclassified hepatitis B cases accounted for 5.8%, 92.4% and 1.8%, respectively. The average age of reported cases was 47 (47±15) years, and males accounted for 64.4%. The average level of alanine aminotransferase was 214.2 (214.2±1 253.4) U/L. The reported cases mainly worked in agriculture, forestry, animal husbandry, fishery, and water conservancy (50.6%, 32 722). The proportions of cases reported from the eastern, western and central regions were 42.5% (27 501),22.1% (14 315) and 35.4% (22 870), respectively. The consistent rate of the clinical types between the reported cases and the verified cases was 58.8%, with a Kappa value of 0.15. For the 39 271 cases confirmed as acute and chronic hepatitis B cases in the reporting cards, the consistent rate of the clinical types between the reported cases and the verified cases was 96.9%, with a Kappa value of 0.73. In 94.5% (24 267/25 681) of the cases with inconsistent clinical types, the reporting card information were incomplete. Conclusion: The diagnosis of hepatitis B has been improved in the hepatitis B surveillance in China, but it is necessary to improve the completeness of the reporting cards of hepatitis B cases to NNDRS.

[Surveillance and response to measles outbreaks in China, 2016-2020].

Objective: To understand the epidemiological characteristics of measles outbreaks in China from 2016 to 2020 and related outbreak investigations and response performances. Methods: The information about the incidence of measles outbreaks, the investigation and response of measles outbreaks in 31 provinces from 2016 to 2020 were collected from Measles Surveillance System, and the incidence of suspected measles outbreaks detected through sporadic case finding during the same period according to the measles outbreak definition was analyzed. Results: From 2016 to 2020, a total of 344 measles outbreaks were reported nationwide, involving 1 886 measles cases. The median of intervals between the first case onsets and reported outbreaks ranged from 4 to 10 days, the median of the numbers of involved cases ranged from 2 to 3, and the median of the duration of the epidemic ranged from 8 to 13 days, and some outbreaks had long durations of 65,44,28,63 and 13 days. The top three provinces with high number of reported outbreaks were Gansu, Beijing and Shandong. Among the reported outbreaks, 115 occurred in communities/villages, accounting for the highest proportion. The genotype identification results indicated that all the outbreaks in 2016 were caused by measles virus H1, and the proportion of the outbreaks caused by measles virus H1 decreased year by year since then, which was 88.57% (31/35) in 2017, 85.00% (17/20) in 2018 and 15.79% (3/19) in 2019 respectively. There was no outbreak caused by measles H1 reported in 2020, the 4 isolates all belonged to genotype D8. Active case findings were conducted in local medical institutions for 313 outbreaks, and measles-containing vaccine coverage surveys were conducted for 266 outbreaks. From 2016 to 2020, a total of 919 suspected measles outbreaks were detected nationwide, involving 4 212 measles cases. The top three provinces with suspected measles outbreaks were Xinjiang, Gansu and Sichuan. The suspected measles outbreaks also mainly occurred in communities/villages (493). Conclusions: The number, scale and duration of measles outbreaks were gradually decreasing, the measles outbreaks at the community level can not be ignored, and the local H1 genotypes tend to be gradually replaced by other genotypes. Improving the sensitivity of outbreak surveillance, promoting vaccination, expanding the vaccine coverage, timely and effective response to the outbreaks are the focus of measles elimination in China in the future.

[Conduct vaccines clinical trials and optimize the immunization strategies].

Development of an effective vaccine requires a long and complicated process. Preclinical studies and phase Ⅰ, Ⅱ, Ⅲ clinical trials mainly focused on the assessment of the vaccine's safety (tolerability), immunogenicity and efficacy before license. After license, it is necessary to further evaluate the actual effectiveness and safety in the general population through phase Ⅳ clinical trials and optimize the immunization strategies with the disease's epidemiology data. In this special issue, published several articles, which reported the main results of pre-license clinical trials and post-marketing evaluation of various vaccines, it was extremely useful to support vaccine licensing and market use. We encourage the continuous clinical studies and post-marketing evaluation of vaccines, including the novel corona virus-19 vaccines, to provide technical support for the population use, under the situation of COVID-19 pandemic.

[Guidelines for the use of post-traumatic tetanus vaccines and passive immune preparation].

Post-traumatic tetanus is the main type of non-neonatal tetanus. To reduce the incidence and mortality rateof tetanus and guide the primary medical institutions to prevent and control tetanus after trauma, the National Immunization Planning Technical Working Group of the Chinese Center for Disease Control and Prevention has compiled this document in the reference with Position Paper by World Health Organization, and the latest research progress both at home and abroad. The guidelines focus on the basic procedures for the prevention and treatment of post-traumatic tetanus, the application of tetanus vaccines and immune preparation, and pre-exposure immunization in high-risk populations of trauma.

[Early containment strategies and core measures for prevention and control of novel coronavirus pneumonia in China].

In December 2019, novel coronavirus pneumonia epidemic occurred in Wuhan, Hubei Province, and spread rapidly across the country. In the early stages of the epidemic, China adopted the containment strategy and implemented a series of core measures around this strategic point, including social mobilization, strengthening case isolation and close contacts tracking management, blocking epidemic areas and traffic control to reduce personnel movements and increase social distance, environmental measures and personal protection, with a view to controlling the epidemic as soon as possible in limited areas such as Wuhan. This article summarizes the background, key points and core measures in the country and provinces. It sent prospects for future prevention and control strategies.

[Guidelines for the use of post-traumatic tetanus vaccines and passive immune preparation].

Post-traumatic tetanus is the main type of non-neonatal tetanus. To reduce the incidence and mortality rate of tetanus and guide the primary medical institutions to prevent and control tetanus after trauma, National Immunization Planning Technical Working Group of the Chinese Center for Disease Control and Prevention has compiled this document in the reference with Position Paper by World Health Organization, the latest research progress from home and abroad. The guidelines focus on the basic procedures for the prevention and disposition of post-traumatic tetanus, the application of tetanus vaccines and immune preparation, and the pre-exposure immunization in high-risk populations of trauma.