This study systematically evaluates factors influencing severe pertussis in Chinese children, providing scientific evidence for its prevention and treatment. A comprehensive search of PubMed, Embase, Web of Science, CNKI, and Wanfang identified literature on factors influencing severe pertussis in Chinese children up to September 30, 2025. We conducted a meta-analysis, and data were combined using either fixed or random models. A total of 24 studies included 839 severe pertussis cases and 4,280 non-severe cases. Severe pertussis was significantly associated with several factors, with the top five strongest associations being: lung consolidation or atelectasis (OR: 15.44; 95%CI: 9.06-26.31), three concave sign (OR: 12.91; 95%CI: 5.46-30.53), elevated C-reactive protein (OR: 5.33; 95%CI: 3.00-9.49), unvaccinated with DTP vaccine (OR: 4.00; 95%CI: 2.86-5.58), and white blood cell count (WMD: 16.42 × 109/L; 95%CI: 9.49-23.36). Early identification of these factors and timely intervention, along with strengthening vaccination efforts for children, can help effectively reduce severe cases.

Background:Despite widespread vaccination, pertussis remains a poorly controlled disease globally and results in substantial annual morbidity and mortality, particularly in young children. Controlled human infection models (CHIMs) using the causative agent Bordetella pertussis are promising systems to enable the study of pertussis disease pathogenesis and immunology and to rapidly assess vaccines and therapeutics. While a pertussis CHIM that produces asymptomatic infection has been established in Europe, the development of a CHIM that leads to symptomatic illness would be advantageous for evaluating vaccine efficacy against both infection and disease. Methods:Healthy participants 18-40 years of age were inoculated intranasally with one of eight doses (ranging from 104 to 108 colony forming units (CFU)) of the pertactin-producing B. pertussis isolate D420 at the challenge facility within the Canadian Center for Vaccinology (Nova Scotia, Canada). The study occurred in two stages. In stage one, the B. pertussis dose was escalated in cohort groups of five to six participants until reaching an endpoint where 70-90% of participants exhibited mild (non-severe, Grade 1 or 2) symptomatic infection, defined as the Human Infectious Dose 70-90 (HID70-90). In stage two, additional challenges were conducted for doses below, at, and above the identified HID70-90 to characterize the emerging pertussis model. For all challenge doses, participants were closely monitored during an inpatient stay of up to 24 days and post-discharge for laboratory-confirmed infection, pertussis symptoms, safety, and IgG antibody responses to four B. pertussis antigens including pertussis toxin, filamentous hemagglutinin, fimbriae, and pertactin. All participants received a five-day course of azithromycin, where timing of initiation depended on B. pertussis testing and symptoms. The study was conducted between July 4, 2022 and March 19, 2025. Findings:Seventy-five participants were inoculated with one of the eight B. pertussis D420 challenge doses and completed the inpatient stay. From the stage-one dose escalation, we found that 107 CFU of B. pertussis D420 was the lowest dose that achieved the HID70-90, where 9 of 12 participants (75·0%) exhibited mild symptomatic infection. Following stage-two challenges, 16 of 22 total participants at 107 CFU (72·7%) developed mild symptomatic infection, thus verifying the HID70-90. The symptomatic infection rate below the HID70-90 at 5×106 CFU of D420 was 20·0% and above the HID70-90 at 5×107 and 108 CFU were 58·3% and 55·6%, respectively. Symptoms with elevated frequency for symptomatic infection (relative to background symptoms in non-infected) included nasal congestion, runny nose, fatigue, malaise, and cough. At the HID70-90, 50% of symptomatic infections included cough. Serological analyses of the four highest (stage-two) challenge doses (5×106, 107, 5×107, 108 CFU) revealed that antibody titres increased over time post-challenge. Seroconversion for at least one of the four studied antibodies was nearly twice as common for symptomatic (70·0%) than asymptomatic (35·7%) infection and was absent (0%) for non-infected. All infections were cleared following azithromycin treatment (100%) and there were no study-related serious adverse events. Interpretation:A safe and reproducible symptomatic pertussis CHIM was achieved, providing a model for research on pertussis disease pathogenesis and immunology and for assessing vaccines and therapeutics. (Clinicaltrials.gov, NCT05136599).

BACKGROUND:Whether rtS106C+H126Y+D134E/rtS106C+H126Y+D134E+L269I (rtCYE/rtCYEI) mutations in the hepatitis B virus (HBV) reverse-transcriptase (RT) region are associated with tenofovir disoproxil fumarate (TDF) resistance is controversial. AIM:To evaluate the presence of the rtCYE/rtCYEI mutations in a large cohort of Chinese patients with chronic HBV infection. METHODS:A total of 28236 patients who underwent drug resistance testing at the Fifth Medical Center of Chinese PLA General Hospital from 2007 to 2019 were enrolled. All patients received nucleoside/nucleotide analogues (NAs) therapy, and serum samples were collected for sequence analysis of the HBV RT domain with mutation analysis. RESULTS:The detection rates of a single mutation of rtS106C, rtH126Y, rtD134E, and rtL269I were 8.21%, 3.20%, 2.55% and 61.49% in 23718 genotype C patients, and 1.31%, 1.76%, 0.21%, and 92.33% in 4266 genotype B patients, respectively. The combined mutations of rtCYE/rtCYEI were only detected in 12 genotype C patients, accounting for 0.042% of all patients. These 12 patients had received NA treatments except TDF before testing. Among them, 6 patients had coexisting rtCYE/rtCYEI and lamivudine-resistance mutations, and 2 patients had coexisting rtCYE/rtCYEI and adefovir-resistance mutations. Compared with the wild-type (WT) strain, the replication capacity of rtCYE/rtCYEI mutants from representative patients decreased by 41.1%-71.8%, and TDF susceptibility reduced by less than 2-fold, but rtCYEI+rtA181V/N236T mutants exhibited a 6.2-/9.9-fold decrease in TDF susceptibility. Molecular modeling showed that rtCYE/rtCYEI mutants had a slight decrease in binding energy to TDF compared to the WT strain. In the clinic, emergence of the rtCYE/rtCYEI mutations was not specifically associated with TDF treatment. CONCLUSION:HBV rtCYE/rtCYEI mutations have a limited effect on TDF susceptibility and are not sufficient to cause TDF resistance.

Background: Global immunization against Haemophilus influenzae type b (Hib) has expanded with Gavi support. We estimated health, economic benefits, equity and cost-effectiveness in 159 countries (1990–2021), and projected effects of future introduction in China. Methods: We used a random forest model to simulate counterfactual scenarios without Hib vaccine introduction in 159 countries (1990–2021) and to project effects of Hib vaccine introduction in China over the next decade. Ten variables were sourced from the World Bank and WHO; Hib disease burden estimates were from the Global Burden of Disease Study 2021. We compared counterfactual and actual results to quantify benefits, equity, and cost-effectiveness. Extensive uncertainty analyses were performed. Results: Between 1990 and 2021, Hib immunization averted an estimated 1,321,123 (95% uncertainty interval [UI] 32,034–2,723,304) deaths and 90,973,504 (95% UI 3,573,718–197,099,799) disability-adjusted life-years globally. Greatest health and economic gains occurred in Africa and low- and middle-income countries (LMICs). Deaths averted decreased with later vaccine introduction (Pearson’s r = −0.56). Vaccination did not improve health equity, and access remains limited in Africa and LMICs. Hib immunization was cost-saving in all countries. In China, introduction at any point in the next decade would provide health and economic benefits and be cost-effective, with earlier introduction yielding greater gains. Conclusions: Hib immunization provide substantial, cost-effective health and economic benefits globally. Persistent inequities in vaccine access for LMICs require targeted solutions. Policymakers in China should consider these findings for future vaccine introduction.

government vaccine subsidies, public trust and individual physical and mental health losses as the core factors, this study develops a finite rationality-based evolutionary game model aimed at exploring evolutionary stabilisation strategies (ESS) in different contexts. Through simulation analyses, it is found that the strict control strategy adopted by the government can significantly enhance its benefits in the context of voluntary public vaccination against the vaccine. Further, when the government implements a strict prevention and control policy and the benefits of public vaccination are significantly increased under this policy, the system will tend to reach the optimal equilibrium state (vaccination, strict prevention and control).

BACKGROUND Liuweiwuling Tablet (LWWL) is a Chinese patent medicine approved for the treatment of chronic inflammation caused by hepatitis B virus (HBV) infection. Previous studies have indicated an anti-HBV effect of LWWL, specifically in terms of antigen inhibition, but the underlying mechanism remains unclear. AIM To investigate the potential mechanism of action of LWWL against HBV. METHODS In vitro experiments utilized three HBV-replicating and three non-HBV-replicating cell lines. The in vivo experiment involved a hydrodynamic injection-mediated mouse model with HBV replication. Transcriptomics and metabolomics were used to investigate the underlying mechanisms of action of LWWL. RESULTS In HepG2.1403F cells, LWWL (0.8 mg/mL) exhibited inhibitory effects on HBV DNA, hepatitis B surface antigen and pregenomic RNA (pgRNA) at rates of 51.36%, 24.74% and 50.74%, respectively. The inhibition rates of LWWL (0.8 mg/mL) on pgRNA/covalently closed circular DNA in HepG2.1403F, HepG2.2.15 and HepG2.A64 cells were 47.78%, 39.51% and 46.74%, respectively. Integration of transcriptomics and metabolomics showed that the anti-HBV effect of LWWL was primarily linked to pathways related to apoptosis (PI3K-AKT, CASP8-CASP3 and P53 pathways). Apoptosis flow analysis revealed that the apoptosis rate in the LWWL-treated group was significantly higher than in the control group (CG) among HBV-replicating cell lines, including HepG2.2.15 (2.92% ± 1.01% vs 6.68% ± 2.04%, P < 0.05), HepG2.A64 (4.89% ± 1.28% vs 8.52% ± 0.50%, P < 0.05) and HepG2.1403F (3.76% ± 1.40% vs 7.57% ± 1.35%, P < 0.05) (CG vs LWWL-treated group). However, there were no significant differences in apoptosis rates between the non-HBV-replicating HepG2 cells (5.04% ± 0.74% vs 5.51% ± 1.57%, P > 0.05), L02 cells (5.49% ± 0.80% vs 5.48% ± 1.01%, P > 0.05) and LX2 cells (6.29% ± 1.54% vs 6.29% ± 0.88%, P > 0.05). TUNEL staining revealed a significantly higher apoptosis rate in the LWWL-treated group than in the CG in the HBV-replicating mouse model, while no noticeable difference in apoptosis rates between the two groups was observed in the non-HBV-replicating mouse model. CONCLUSION Preliminary results suggest that LWWL exerts a potent inhibitory effect on wild-type and drug-resistant HBV, potentially involving selective regulation of apoptosis. These findings offer novel insights into the anti-HBV activities of LWWL and present a novel mechanism for the development of anti-HBV medications.

Background: Hepatitis B virus (HBV) infection is a high-risk factor for severe COVID-19 cases, leading clinicians to enhance the monitoring of patients with concurrent HBV and COVID-19 infections. However, this focus is typically on patients with active HBV infection. Patients who are HBV surface antigen (HBsAg) negative and HBV core antibody (anti-HBc) positive are often considered to have either a past infection that has naturally cleared or to be in a low-replication state, and thus receive less clinical attention. However, in immunosuppressed states, such as during immunosuppressive treatment following COVID-19 infection, the virus in these patients may reactivate. In such cases, this reactivation can increase the risk of COVID-19 progressing to a severe illness. Therefore, being HBsAg negative and anti-HBc positive could be a potential risk factor for severe COVID-19. Studying the combination of anti-HBc positivity and COVID-19 infection can help identify high-risk populations, allowing for the implementation of targeted prevention and management measures, thereby reducing the occurrence of severe COVID-19 cases. Objectives: To establish and evaluate a model for predicting severe pneumonia in patients with positive anti-HBc combined with COVID-19 infection. Methods: We retrospectively enrolled 380 patients who tested positive for anti-HBc, negative for HBsAg, and HBV e-antigen (HBeAg), combined with COVID-19 infection, in our hospital from December 2022 to May 2023. Based on the inclusion criteria, 163 patients were included in the study. We applied the Lasso binary logistic regression model to optimize feature selection, identifying eight non-zero coefficients using a minimum of one standard error. Using the multiple logistic regression method with backward selection, we screened six factors from the eight selected by the Lasso binary logistic regression model. These six factors were used to construct the predictive model and a nomogram. The validity of our nomogram was assessed using the area under the receiver operating characteristic curve (AUC), calibration curve, Hosmer-Lemeshow (HL) test, and decision-curve analysis (DCA). Results: Hypertension, diabetes, decreased absolute lymphocyte count, prolonged prothrombin time, elevated aspartate aminotransferase, and decreased albumin are high-risk factors for severe pneumonia in patients with positive anti-HBc combined with COVID-19 infection. The AUC of the predictive model constructed using these six factors is 0.785, with a 95% confidence interval of (0.709-0.862). The HL test, performed using the calibration curve, yielded a p-value of 0.868. The application of this diagnostic curve will increase the net benefit when the threshold probability is between 5% and 75%. Conclusions: The constructed nomogram can be used to predict the risk of patients with positive anti-HBc combined with COVID-19 infection progressing to severe pneumonia, based on routine blood parameters, liver function, coagulation, lactate dehydrogenase levels, and the patient's underlying disease. The predictive model demonstrates good discrimination, calibration, and clinical utility.

Previous studies did not provide substantial evidence for long-term immune persistence after the hepatitis B vaccine (HepB) in preterm birth (PTB) children. Consequently, there is ongoing controversy surrounding the booster immunization strategy for these children. Therefore, we conducted a retrospective cohort study to evaluate the disparities in immune persistence between PTB children and full-term children. A total of 1027 participants were enrolled in this study, including 505 PTB children in the exposure group and 522 full-term children in the control group. The negative rate of hepatitis B surface antibody (HBsAb) in the PTB group was significantly lower than that in the control group (47.9% vs. 41.4%, p = .035). The risk of HBsAb-negative in the exposure group was 1.5 times higher than that in the control group (adjusted odds ratio [aOR] = 1.5, 95% confidence interval [CI]: 1.1-2.0). The geometric mean concentration (GMC) of HBsAb was much lower for participants in the exposure group compared to participants in the control group (9.3 vs. 12.4 mIU/mL, p = .029). Subgroup analysis showed that the very preterm infants (gestational age <32 weeks) and the preterm low birth weight infants (birth weight <2000 g) had relatively low GMC levels of 3.2 mIU/mL (95% CI: 0.9-11.1) and 7.9 mIU/mL (95% CI: 4.2-14.8), respectively. Our findings demonstrated that PTB had a significant impact on the long-term persistence of HBsAb after HepB vaccination. The very preterm infants (gestational age <32 weeks) and the preterm low birth weight infants (birth weight <2000 g) may be special populations that should be given priority for HepB booster vaccination.

IntroductionAn extended-spectrum beta-lactamase (ESBL)-hypervirulent Klebsiella pneumoniae (HvKP) strain HKE9 was isolated from the blood in an outpatient.MethodsThe effect of the global regulatory factor RpoS on antimicrobial resistance, pathogenicity, and environmental adaptability was elucidated.ResultsHKE9 is a novel ST3355 (K20/O2a) hypervirulent strain with a positive string test and resistant to cephems except cefotetan. It has a genome size of 5.6M, including two plasmids. CTX-M-15 was found in plasmid 2, and only ompk37 was found in the chromosome. HKE9 could produce bacterial siderophores, and genes of enterobactin, yersiniabactin, aerobactin, and salmochelin have been retrieved in the genome. As a global regulatory factor, knockout of rpoS did not change antimicrobial resistance or hemolytic phenotype while increasing the virulence to Galleria mellonella larvae and showing higher viscosity. Moreover, rpoS knockout can increase bacterial competitiveness and cell adhesion ability. Interestingly, HKE9-M-rpoS decreased resistance to acidic pH, high osmotic pressure, heat shock, and ultraviolet and became sensitive to disinfectants (H2O2, alcohol, and sodium hypochlorite). Although there were 13 Type 6 secretion system (T6SS) core genes divided into two segments with tle1 between segments in the chromosome, transcriptomic analysis showed that rpoS negatively regulated T4SS located on plasmid 2, type 1, and type 3 fimbriae and positively regulate genes responsible for acidic response, hyperosmotic pressure, heat shock, oxidative stress, alcohol and hypochlorous acid metabolism, and quorum sensing.DiscussionHere, this novel ST3355 ESBL-HvKP strain HKE9 may spread via various clonal types. The important regulation effect of rpoS is the enhanced tolerance and resistance to environmental stress and disinfectants, which may be at the cost of reducing virulence and regulated by T4SS.

Dengue fever (DF) and dengue hemorrhagic fever (DHF) are among the most common tropical diseases affecting humans. To analyze the risk of clinical and transmission of DF/DHF in Shenzhen, the surveillance on patients of all-age patients with dengue virus (DENV) infections was conducted. Our findings revealed that the majority of DENV-infected patients are young to middle-aged males, and the development of the disease is accompanied by abnormal changes in the percentages of neutrophils, lymphocytes, and basophils. Demographic analysis revealed that these patients is concentrated in areas such as Futian District, which may be due to the higher mosquito density and temperature than that in other area. Subsequent, mosquito infection experiments confirmed that the effect of temperature shift on DENV proliferation and transmission. Not only that, constant temperatures can enhance the spread of DENV, even increase the risk of epidemic. Thus, the role of innate immune response should be highlighted in the prediction of severe severity of DENV-infected patients, and temperature should be taken into account in the prevention and control of DENV.Introduction: Dengue fever (DF) and dengue hemorrhagic fever (DHF) are among the most common tropical diseases affecting humans, and which caused by the four dengue virus serotypes (DENV 1-4). Objectives: To analyze the risk of clinical and transmission of DF/DHF in Shenzhen.Methods: The surveillance on patients of all-age patients with dengue virus (DENV) infections was conducted.Results: Our findings revealed that the majority of DENV-infected patients are young to middle-aged males, and the development of the disease is accompanied by abnormal changes in the percentages of neutrophils, lym-phocytes, and basophils. Demographic analysis revealed that these patients is concentrated in areas such as Futian District, which may be due to the higher mosquito density and temperature than that in other area. Subsequent, mosquito infection experiments confirmed that the effect of temperature shift on DENV proliferation and transmission. Not only that, constant temperatures can enhance the spread of DENV, even increase the risk of epidemic. Conclusion: 1. Elevated levels of neutrophils, lymphocytes, basophils, and temperature are all significant risk factors for dengue transmission and pathogenesis; 2. Temperature increasing is associated with a higher risk of dengue transmission; 3. Fluctuations in temperature around 28 degrees C (28 & PLUSMN; 5 degrees C) would increase dengue transmission.

The aim of this study was to evaluate the seroprevalence of rubella antibodies and factors associated with antibody seropositivity after vaccination among healthy children aged 14 and below. A multi-stage stratified random sampling method was employed to recruit participants for the rubella serological test. An enzyme-linked immunosorbent assay method was used to detect human IgG antibodies with avidity for rubella virus in the sera of participants. Univariate and multivariate analyses were used to analyze associations between variables. A total of 778 subjects were included in the subsequent analysis. The overall positive rate of rubella antibody was 83.0% (95%CI: 80.2–85.5%), and the overall geometric mean concentration (GMC) was 58.05 IU/ml. In multivariate analysis, gender, residence, birth year group, and time since the last rubella-containing vaccines (RCV) vaccination were significantly associated with the seroprevalence of rubella antibodies. Our study showed a decreasing trend in rubella antibody positivity and GMC in the population aged five to 14 years. Therefore, we recommend a catch-up dose of RCV for adolescents and young people aged over 14 years not yet vaccinated.

Teachers played an important role on the transmission of influenza in schools and communities. The study aims to investigate the influenza vaccination coverage and the factors determining flu vaccination acceptance among teachers in Hangzhou, China. A total of 1039 junior high school teachers in Hangzhou were recruited. The self-made questionnaire was used to investigate the influenza vaccine coverage among teachers and the influencing factors of influenza vaccination acceptance. Univariate analysis using the chi-square test and multivariable analysis using binary logistic regression were conducted to determine the relative predictors. The Influenza vaccine coverage among teachers was 5.9% (62/1039). 52.9% of teachers had the intention to receive influenza vaccine, 25.3% (247/977)/21.8% (213/977) of participants was hesitant/did not have the intention to get influenza vaccine. The top three sources for teachers to gain knowledge about influenza were website (72%), TV/radio (66.1%) and social media (58%). Whether get influenza vaccination before, knowledge about influenza and influenza vaccine, the beliefs for the likelihood of catching flu, the severity of getting flu, the effectiveness of influenza vaccine, the possibility of side effects after vaccination, and the troublesome of vaccination, doctors' recommendation, as well as the situation of vaccination among other teachers were the associated factors of influenza vaccination acceptance. The influenza vaccination coverage was low but the intentions were relatively high among junior high school teachers. Future research should focus on the relationship between vaccination acceptance and behavior to increase influenza vaccination rates.

Background Although influenza vaccination is recommended for people aged 70 and above in Hangzhou, and the vaccine is provided free of charge, the elderly influenza vaccination rate is still low. The purpose of this study was to understand the barriers and motivations of older people in deciding to receive free influenza vaccine through questionnaires. Methods The method of stratified random sampling was adopted to take samples. A questionnaire survey was conducted among the elderly aged 70 years and above by face-to-face interview or telephone interview. Results A total of 11,663 elderly people aged 70–100 years were successfully and effectively interviewed. 85.98% of the respondent were willing to get the influenza shot, 8.91% were unwilling to get the influenza shot, and 5.11% were on vaccine hesitancy. The people of age of 70–79 years old (hesitancy: OR 70~79 = 0.668, 95% CI : 0.571 0.782, Unwilling: OR 70 − 79 = 0.755, 95% CI : 0.622 0.916), primary school degree or below (hesitancy: OR Secondary school degree or above = 1.467, 95% CI : 1.249 1.724, Unwilling: OR Secondary school degree or above = 1.255, 95% CI : 1.028 1.535), remote areas (hesitancy: OR near central urban area = 2.111, 95% CI : 1.604 2.778, OR central urban area = 2.957, 95% CI : 2.255 3.877, Unwilling: OR near central urban area = 1.687, 95% CI : 1.230 2.313. OR centralurbanarea = 2.218, 95% CI : 1.626 3.027), and convenient for movement (hesitancy: OR yes = 0.494, 95% CI : 0.420 0.580, Unwilling: OR yes = 0.585, 95% CI : 0.480 0.713), understanding of the free vaccine policy (hesitancy: OR understand = 0.204, 95% CI : 0.171 0.245, Unwilling: OR understand = 0.164, 95% CI : 0.128 0.210), influenza knowledge level≥ 13 points (hesitancy: OR ≥13 points = 0.628, 95% CI : 0.533 0.739, Unwilling: OR ≥13 points = 0.538, 95% CI : 0.437 0.662), influenza vaccine knowledge level≥ 12 points (hesitancy: OR ≥12 points = 0.422, 95% CI : 0.350 0.508, Unwilling: OR ≥12 points = 0.370, 95% CI : 0.290 0.472), and social trust level ≥ 12 points (hesitancy: OR ≥12 points = 0.134, 95% CI : 0.112 0.160, Unwilling: OR ≥12 points = 0.220, 95% CI : 0.180 0.269) are more willing to receive free influenza vaccine. Conclusion The proportion of elderly people aged 70 and above who are willing to receive free influenza vaccine is high in Hangzhou. But the level of knowledge about influenza, vaccine and trust in society is low. The government should continue to improve the elderly's awareness and trust in society through medical staff, family members, television and radio media, and guide the elderly to actively vaccinate against influenza. Effective publicity should be carried out through the above channels to guide the elderly to actively vaccinate against influenza.

ObjectiveDuring the COVID-19 epidemic, vaccination staff had three main aspects of work: routine vaccination for children and adults, COVID-19 vaccination and COVID-19 prevention and control. All these works significantly increased the workload of vaccination staff. This study aimed to investigate the prevalence and influencing factors of burnout among vaccination staff in Hangzhou, China.MethodsA total of 501 vaccination staff from 201 community/township healthcare centers in Hangzhou were recruited using a cross-sectional survey through WeChat social platform. The Maslach Burnout Inventory-General Scale (MBI-GS) was used to assess the level of burnout. Descriptive statistics were made on the characteristics of participants. Univariate analysis using the chi-square test and multivariable analysis using binary logistic regression were conducted to determine the relative predictors of burnout. Univariate analysis and multiple linear regression were used to determine the relative predictors of exhaustive emotion, cynicism, and personal accomplishment.ResultsDuring the COVID-19 pandemic, 20.8% of the vaccination staff experienced burnout. Educational level above undergraduate education level, medium professional title, and more working time in COVID-19 vaccination work reported a higher degree of job burnout. The vaccination staff was experiencing a high degree of exhaustive emotion, cynicism, and low personal accomplishment. Professional title, working place, and working time for COVID-19 vaccination were associated with exhaustive emotion and cynicism. Professional title and participation time for COVID-19 prevention and control were associated with personal accomplishment.ConclusionsOur findings suggest that the prevalence rate of burnout is high among vaccination staff during the COVID-19 pandemic, especially with a low level of personal accomplishment. Psychological intervention for vaccination staff is urgently needed.

Background13-valent pneumococcal polysaccharide conjugate vaccine (PCV13) has been introduced in Hangzhou since 2017, whereas its current immunization state in children is not clear. Therefore, this study aims to describe the PCV13 vaccination distribution among children born in Hangzhou from 2017 to 2021 to provide data for reducing vaccination differences among different populations. MethodsDescriptive epidemiology was used for data analysis and PCV13 vaccination related information of children was collected from children vaccination management system of Zhejiang Province (ZJCVMS). ResultsAmong the 649,949 children born in Hangzhou from 2017 to 2021, 169,230 were vaccinated with an average full course vaccination rate of 26.0%. The full course vaccination rates in 5 years were different (P = 0.000) with an increasing trend (P (fortrend) < 0.01). The first dose vaccination rates were different in 5 years (P = 0.000) with an increasing trend (P (fortrend) < 0.01). The distribution of age when first dose PCV13 was administered varied, most people at 2 months and least people at 5 months. The full course vaccination rate varied by areas, highest in central urban areas and lowest in remote areas respectively (all P-value < 0.05). Overall, the full course vaccination rate of PCV13 was higher in the registered residence population than the non-registered residence population, which was 136,693 (31.4%) and 32,537 (15.1%) respectively (P = 0.000). The full course vaccination rates were the same between men and women (P = 0.502), which was 87,844 for men (26.0%) and 81,386 for women (26.1%). ConclusionAlthough the number of people who received PCV13 full course vaccination and received the first dose vaccination showed yearly increasing trends in Hangzhou, the full course vaccination rate for the whole population was relatively low. In addition, the PCV13 vaccination rates also differed by geography and household registration status. Measures such as expanding vaccination publicity or including national immunization should be taken to increase vaccination rates and reduce the differences in vaccination among groups with different characteristics.

Abstract Background Although COVID-19 vaccines and their booster regimens protect against symptomatic infections and severe outcomes, there is limited evidence about their protection against asymptomatic and symptomatic infections in real-world settings, particularly when considering that the majority of SARS-CoV-2 Omicron infections were asymptomatic. We aimed to assess the effectiveness of the booster dose of inactivated vaccines in mainland China, i.e., Sinopharm (BBIBP-CorV) and Sinovac (CoronaVac), against Omicron infection in an Omicron BA.5 seeded epidemic. Methods Based on an infection-naive but highly vaccinated population in Urumqi, China, the study cohort comprised all 37,628 adults who had a contact history with individuals having SARS-CoV-2 infections, i.e., close contacts, between August 1 and September 7, 2022. To actively detect SARS-CoV-2 infections, RT-PCR tests were performed by local authorities on a daily basis for all close contacts, and a testing-positive status was considered a laboratory-confirmed outcome. The cohort of close contacts was matched at a ratio of 1:5 with the fully vaccinated (i.e., 2 doses) and booster vaccinated groups (i.e., 3 doses) according to sex, age strata, calendar date, and contact settings. Multivariate conditional logistic regression models were adopted to estimate the marginal effectiveness of the booster dose against Omicron BA.5 infection after adjusting for confounding variables. Subgroup analyses were performed to assess vaccine effectiveness (VE) in different strata of sex, age, the time lag from the last vaccine dose to exposure, and the vaccination status of the source case. Kaplan–Meier curves were employed to visualize the follow-up process and testing outcomes among different subgroups of the matched cohort. Findings Before matching, 37,099 adult close contacts were eligible for cohort enrolment. After matching, the 2-dose and 3-dose groups included 3317 and 16,051 contacts, and the proportions with Omicron infections were 1.03% and 0.62% among contacts in the 2-dose and 3-dose groups, respectively. We estimated that the adjusted effectiveness of the inactivated booster vaccine versus 2 doses against Omicron infection was 35.5% (95% CI 2.0, 57.5). The booster dose provided a higher level of protection, with an effectiveness of 60.2% (95% CI 22.8, 79.5) for 15–180 days after vaccination, but this VE decreased to 35.0% (95% CI 2.8, 56.5) after 180 days. Evidence for the protection of the booster dose was detected among young adults aged 18–39 years, but was not detected for those aged 40 years or older. Interpretation The receipt of the inactivated vaccine booster dose was associated with a significantly lower Omicron infection risk, and our findings confirmed the vaccine effectiveness (VE) of booster doses against Omicron BA.5 variants. Given the rapid evolution of SARS-CoV-2, we highlight the importance of continuously monitoring the protective performance of vaccines against the genetic variants of SARS-CoV-2, regardless of existing vaccine coverage.

IMPORTANCE In 2022, Omicron variants circulated globally, and Urumqi, China, experienced a COVID-19 outbreak seeded by Omicron BA.5 variants, resulting in the highest number of infections in the city's record before the exit of the zero COVID-19 strategy. Little was known about the characteristics of Omicron variants in mainland China. OBJECTIVE To evaluate transmission characteristics of Omicron BA.5 variants and the effectiveness of inactivated vaccine (mainly BBIBP-CorV) against their transmission. DESIGN, SETTING, AND PARTICIPANTS This cohort study was conducted using data from an Omicron-seeded COVID-19 outbreak in Urumqi from August 7 to September 7, 2022. Participants included all individuals with confirmed SARS-CoV-2 infections and their close contacts identified between August 7 and September 7, 2022 in Urumqi. EXPOSURES A booster dose was compared vs 2 doses (reference level) of inactivated vaccine and risk factors were evaluated. MAIN OUTCOMES AND MEASURES Demographic characteristics, timeline records from exposure to laboratory testing outcomes, contact tracing history, and contact settingwere obtained. The mean and variance of the key time-to-event intervals of transmission were estimated for individuals with known information. Transmission risks and contact patterns were assessed under different diseasecontrol measures and in different contact settings. The effectiveness of inactivated vaccine against the transmission of Omicron BA.5 was estimated using multivariate logistic regression models. RESULTS Among 1139 individuals diagnosed with COVID-19 (630 females [55.3%]; mean [SD] age, 37.4 [19.9] years) and 51 323 close contacts who tested negative for COVID-19 (26 299 females [51.2%]; mean [SD] age, 38.4 [16.0] years), the means of generation interval, viral shedding period, and incubation period were estimated at 2.8 days (95% credible interval [CrI], 2.4-3.5 days), 6.7 days (95% CrI, 6.4-7.1 days), and 5.7 days (95% CrI, 4.8-6.6 days), respectively. Despite contact tracing, intensive control measures, and high vaccine coverage (980 individuals with infections [86.0%] received similar to 2 doses of vaccine), high transmission risks were found in household settings (secondary attack rate, 14.7%; 95% CrI, 13.0%-16.5%) and younger (aged 0-15 years; secondary attack rate, 2.5%; 95% CrI, 1.9%-3.1%) and older age (aged >65 years; secondary attack rate, 2.2%; 95% CrI, 1.5%-3.0%) groups. Vaccine effectiveness against BA.5 variant transmission for the booster-dose vs 2 doses was 28.9%(95% CrI, 7.7%-45.2%) and 48.5%(95% CrI, 23.9%-61.4%) for 15-90 days after booster dose. No protective outcome was detected beyond 90 days after the booster dose. CONCLUSIONS AND RELEVANCE This cohort study revealed key transmission characteristics of SARS-CoV-2 as they evolved, as well as vaccine effectiveness against variants. These findings suggest the importance of continuously evaluating vaccine effectiveness against emerging SARS-CoV-2 variants.