Objective:To construct a nanoparticle vaccine displaying the prefusion F (preF) protein of respiratory syncytial virus (RSV) using the I53-50 protein nanoparticle platform, and to systematically evaluate its immunogenicity and protective efficacy.Methods:The RSV preF trimer antigen was genetically fused to I53-50A and assembled in vitro with I53-50B to form preF-I53-50 nanoparticles, theoretically displaying 20 preF antigens per particle. The structure and purity were characterized by size-exclusion chromatography, SDS-PAGE, and negative-stain electron microscopy. BALB/c mice were intramuscularly immunized with varying doses (1 μg or 5 μg) of preF antigen or an equimolar amount of preF-I53-50 nanoparticles. Humoral immunity, B-cell responses, and protective efficacy were assessed following intranasal viral challenge.Results:The preF-I53-50 nanoparticles self-assembled into spherical structures (50-60 nm in diameter) with uniformly arrayed antigens. The nanoparticle vaccine enhanced RSV-specific IgG1 and IgG2a antibody responses, promoting a Th1-biased immune profile. At equimolar preF doses, the neutralizing antibody titers induced by 1 μg and 5 μg nanoparticle formulations were 2.8-fold and 2.3-fold higher, respectively, than those elicited by preF alone ( P<0.05). Notably, even the low-dose nanoparticle group outperformed the high-dose preF group (1.6-fold increase). Viral challenge experiments demonstrated that preF-I53-50 effectively suppressed pulmonary viral replication, mitigated pathological damage, and induced stronger germinal center and memory B-cell responses, suggesting enhanced B-cell affinity maturation and long-term immune memory. Conclusion:The preF-I53-50 vaccine improves the immunogenicity and protective efficacy of RSV preF through multivalent antigen display.

Objective:To evaluate the protective effectiveness (VE) of the acellular pertussis vaccine (aPV) against pertussis in children aged 2 months to 6 years.Methods:A test-negative case-control study was conducted among children aged 2 months to 6 years who sought medical care for cough and underwent pertussis nucleic acid testing at sentinel surveillance hospitals in Zhejiang Province in 2024. Cases were defined as those with positive pertussis nucleic acid test results, while controls were test-negative individuals matched 1∶1 based on propensity scores using the caliper matching method. Conditional logistic regression models were used to calculate odds ratios ( ORs) and VEs. Results:Among the 658 participants, 31.76% (209 cases) tested positive for pertussis. After propensity score matching, 203 cases and 203 controls were included in the analysis. The VE of 1-2, 3, and 4 doses of aPV against pertussis was 52.46% (95% CI:-39.82%-83.84%), 65.22% (95% CI: 6.86%-87.02%), and 72.21% (95% CI: 34.33%-88.24%), respectively. For pertussis-related hospitalization, the VE of 1-3 and 4 doses was 80.95% (95% CI:31.38%-94.71%) and 86.79% (95% CI: 51.89%-96.37%). The VE for those who completed 4 doses of vaccination and had intervals of less than 2 years, 2 years, 3 years, and 4 years or more after vaccination were 91.15% (95% CI: 67.61%-97.58%), 84.70% (95% CI: 43.71%-95.84%),56.23% (95% CI:-47.58%-87.02%), and 49.92% (95% CI:-83.74%-86.35%), respectively. Conclusion:The VE of aPV against pertussis in children aged 2 months to 6 years increases with the number of doses administered, and it is more effective in preventing hospitalization due to pertussis. The VE declines rapidly over time after the last dose. It is recommended to follow the new pertussis immunization program for timely and full vaccination.

Objective:To analyze the epidemic trend and spatiotemporal distribution characteristics of pertussis in Shandong Province from 2015 to 2024.Methods:Data on pertussis cases in Shandong Province from 2015 to 2024 were collected from the China Information System for Disease Control and Prevention. The ArcGIS spatiotemporal method was used to analyze the epidemic trend and spatiotemporal distribution characteristics of pertussis, and determine the hotspots of incidence.Results:From 2015 to 2024, 46 172 cases of pertussis were reported in Shandong Province, with an average annual incidence rate of about 4.60/100 000. The reported incidence rate showed an overall upward trend, and in 2024, the reported incidence rate reached the highest level in history (19.20/100 000) since the implementation of children′s planning immunization. The areas with high incidence rates were mainly located in the central and western regions of Shandong Province, including Jinan city, Liaocheng city, Tai′an city, Zibo city, Binzhou city, Jining city, Dezhou city, Zaozhuang city, and Dongying city. The global spatial autocorrelation analysis showed that the Moran′s I index of incidence rate of pertussis in Shandong Province in each year from 2015 to 2024 was >0.00, showing obvious spatial clustering. Local spatial autocorrelation analysis showed that the "high high" clustering areas were mainly distributed in some counties (cities, districts) in the central and western regions of Shandong Province, which were hotspots for pertussis incidence in Shandong Province. The spatial trend surface analysis showed that the annual incidence rate of pertussis in each year basically decreased from west to east. In the early stage of the north-south direction, there was a curved trend of low north-south and high in the middle. In the middle and later stages, the northern part was mostly in a higher position, indicating that the central and western regions were the high-risk areas for pertussis in Shandong Province. Conclusions:The pertussis epidemic in Shandong Province from 2015 to 2024 has obvious spatiotemporal clustering, and the central and western regions are the key areas for pertussis prevention and control.

Objective:To analyze the molecular characteristics of prevalent Bordetella pertussis (Bp) isolates in Liaocheng City, Shandong Province in 2024. Methods:From March to August 2024, oropharyngeal swabs were collected from suspected pertussis cases at Liaocheng People′s Hospital in Shandong Province for Bp isolation. A total of 99 Bp isolates were obtained. Whole-genome sequencing was performed on all isolates, followed by Multilocus Sequence Typing (MLST), vaccine antigen-related gene typing (including ptxP, ptxA, ptxB, ptxC, ptxD, ptxE, fhaB, fim2, fim3, and prn), 23S rRNA gene typing, and phylogenetic analysis. To capture the differences between Bp isolates and vaccine strains in Liaocheng City, the international vaccine strain Tohama I and the Chinese vaccine strain CS were included in the analysis. Antimicrobial resistance testing against 11 agents was performed on 52 isolates. Results:The throat swabs of 99 Bp isolates were collected from patients aged 44 days to 42 years, and the median age of the patients was 7 (5, 8) years. All isolates ptxP were ptxP3 type. 74 isolates (74.75%) carried the prn150, while 21 isolates (21.21%) were prn-deficient. The predominant antigenic profile was ptxP3/ ptxA1/ ptxB1/ ptxC4/ ptxD1/ ptxE4/ fhaB1/ fim2-1/ fim3-1/ prn150, found in 72 isolates (72.73%). All 99 isolates carried the A2047G mutation in the 23S rRNA gene. Antimicrobial susceptibility testing showed that the MICs of macrolides and clindamycin for all 52 Bp isolates were all >256 mg/L. However, the isolates showed low MIC for seven other antimicrobials tested, including trimethoprim-sulfamethoxazole, amoxicillin, and levofloxacin. MLST typing revealed that 94 isolates (94.95%) were identified as ST-2, while 5 isolates (5.05%) belonged to a novel sequence type (ST-118). Phylogenetic analysis demonstrated that all 99 Bp isolates were highly homologous but clustered in evolutionary branches distinct from vaccine strains. Conclusion:In 2024, Bordetella pertussis isolates in Liaocheng City exhibit distinct clonal epidemic characteristics, with the predominant antigenic genotype being ptxP3/ ptxA1/ ptxB1/ ptxC4/ ptxD1/ ptxE4/ fhaB1/ fim2-1/ fim3-1/ prn150. All isolates are resistant to macrolide antibiotics.

Objective:To analyze the prevalence and clinical characteristics of pertussis in children with different cough durations.Methods:From January 2021 to October 2022, information on children aged 0-18 years who visited eight hospitals in Shandong Province due to cough was enrolled. Pertussis serological antibody testing and/or nucleic acid testing were performed. The prevalence and clinical characteristics of pertussis were compared among the acute cough group, protracted cough group, and chronic cough group using the χ2 test or Fisher′s exact test. Results:A total of 1 565 children with cough were included in the study, of which 348 (22.24%) were laboratory-confirmed pertussis. There was a significant difference in the laboratory-confirmed rate of pertussis among different cough groups ( χ2=83.424, P<0.001). The confirmation rate of pertussis in the protracted cough group (42.21%) was significantly higher than that in the acute cough group (16.49%, P<0.05) and chronic cough group (19.50%, P<0.05). In each cough group, the age of children was significantly associated with the confirmed rate of pertussis, and the confirmed rate was relatively high in children aged 3 months to <2 years. Pertussis vaccination was significantly associated with the confirmed rate in all groups, and the confirmed rate was higher in unvaccinated children. Among laboratory-confirmed pertussis cases, the incidence of typical symptoms such as paroxysmal cough, whoop, and post-tussive emesis or sleep disturbance was significantly higher than that in the non-confirmed cases. In the protracted and chronic cough groups, the proportion of non-confirmed cases complicated with asthma/cough variant asthma (CVA) was significantly higher than that in pertussis-confirmed cases. Conclusion:There are differences in the confirmation rate of pertussis among children with different cough durations. The confirmation rate is significantly associated with age, vaccination status, and clinical symptoms. Enhancing clinical vigilance against pertussis, conducting early diagnosis, and getting timely and standardized vaccination are crucial for effectively controlling pertussis and preventing outbreaks.

Objective:To evaluate the epidemiological protective effect of a booster dose of acellular DTP vaccine (DTaP) against pertussis in 6-year-old children.Methods:A retrospective cohort study was conducted to compare the incidence of pertussis in 6-year-old children who received DTaP versus DT vaccine boosters in 2023 over a two-year period from May 2023 to May 2025. The protective effect of the fifth dose of DTaP against pertussis in 6-year-old children was evaluated.Results:A total of 960 participants were enrolled in this study, including 480 children in the experimental group who received the fifth dose of DTaP vaccine and 480 children in the control group who received the DT vaccine booster. Baseline characteristics were balanced between the two groups. There were six confirmed cases of pertussis in the experimental group, with a reported incidence rate of 1.25%. In the control group, 14 pertussis cases were reported, with a reported incidence rate of 2.92%. The protective effectiveness(VE) of the DTaP vaccine against pertussis was 57.14% (95% CI:-10.59%-83.39%). For 6-year-old children who completed the booster immunization, the incidence data of pertussis were collected from the 14 th day after vaccination (i.e., the study day 0). Based on the annual cumulative incidence rate, the VE of DTaP against pertussis at 6, 12, 18, and 24 months after vaccination was 100%, 63.80% (95% CI:-14.49%-88.55%), 64.59% (95% CI: 1.17%-87.31%), and 57.60% (95% CI:-10.80%-83.78%), respectively. In the DTaP group, the annual cumulative incidence rate of 12 to 24 months did not show a significant upward or downward trend ( Z=-0.995, P=0.320). Conclusion:Boosting 6-year-old children with the DTaP vaccine provides measurable protection against pertussis. The protective efficacy is significant in the early stage (0 to 6 months) after vaccination, and it still remains effective at 12 to 24 months.

To analyze the epidemiological characteristics and spatiotemporal distribution of pertussis in Tianjin City from 2010 to 2024. Data on pertussis cases reported in Tianjin between January 1, 2010, and December 31, 2024, were extracted from the Infectious Disease Surveillance and Reporting Information System of the China Information System for Disease Control and Prevention. Descriptive epidemiological methods and Joinpoint regression were used to analyze the temporal distribution and incidence trends of pertussis. Spatial autocorrelation analysis and spatial-temporal scanning were employed to characterize the spatial distribution and clustering patterns. The incidence rate of pertussis in Tianjin exhibited an overall upward trend from 2010 to 2024 (AAPC=17.04%, P<0.001), peaking at 11.70 per 100 000 population in 2023. Prior to 2020, the incidence peaked in July and August, whereas from 2023 to 2024, high incidence periods shifted to autumn and winter. The highest average annual incidence rate occurred in the <1-year-old group (165.06 per 100 000), followed by the 5-9-year-old group (20.14 per 100 000). The groups under 1 year old and 1-4 years old showed a trend of first increasing, then decreasing, and subsequently increasing again, with 2018 and 2021 as turning points ( P<0.05). Global spatial autocorrelation analysis revealed significant spatial clustering of pertussis cases in Tianjin districts in 2017 ( Moran′s I=0.19) and 2023 ( Moran′s I=0.51), with both P<0.05. The spatial-temporal scan analysis identified nine high-incidence clusters, with the primary cluster occurring in 2023, covering Jinnan, Dongli, and Hexi districts ( RR=7.37, LLR=568.21, P<0.001). In summary, the incidence of pertussis in Tianjin City has shown an upward trend from 2010 to 2024. The epidemiological characteristics have significantly changed around 2020, with pronounced seasonal and spatial clustering patterns observed in the past two years.

To clarify the epidemiological characteristics of pertussis in children in Hanzhong during the nationwide surge in pertussis, this study retrospectively collected nucleic acid testing data of 4 565 children with pertussis from a tertiary hospital in Hanzhong City from September 2023 to August 2024, and collected demographic and clinical information of confirmed cases for analysis. The results showed that among 4 565 cases tested, there were 1 224 positive cases for pertussis nucleic acid testing, with a total positive rate of 26.81%. Since September 2023, the number of tests and positive cases had continuously increased, reaching a peak in May 2024, with 1 174 samples tested and 319 positive cases. Notably, the number of confirmed cases from April to July 2024 accounted for 82.03% (1 004/1 224) of the total confirmed cases during the study period. Among the 1 224 confirmed cases of pertussis, there were 647 male patients (52.86%) and 577 female patients (47.14%). The highest proportion of cases was found in school-age and preschool children, accounting for 88.81% (1 087/1 224). Among outpatients, school-age and preschool children accounted for 93.44% (897/960), while inpatient cases were mainly preschool, school-age children, and infants (94.32%, 249/264). The positive detection rates of outpatient and inpatient children in the same age group were compared. Except for the infant group, the positive rates of the other four groups were higher than those of the inpatient group (all P<0.05). Among 264 hospitalized children with pertussis, 70 cases (26.52%, 70/264) were infected with Bordetella pertussis alone, and 194 cases (73.48%, 194/264) had co-infections with other pathogens. Rhinovirus, Mycoplasma pneumoniae, and Staphylococcus aureus were the most common pathogens in co-infections.

Objective:To construct a questionnaire to measure parents′ behavioral and social drivers (BeSD) in administering rotavirus vaccine to their children, and to test the reliability and validity of the questionnaire.Methods:A questionnaire was constructed to investigate the BeSD of rotavirus vaccination among parents based on the WHO BeSD questionnaire. A survey was conducted among parents of children aged 0-3 years old in vaccination clinics from 15 community health service centers in Nanjing City of Jiangsu Province, Yuhuan and Kaihua Counties of Zhejiang Province, Anqing City of Anhui Province, and Yangpu District of Shanghai City from April to May in 2024. Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were used to analyze the reliability (internal consistency reliability, combination reliability and split half reliability) and validity (structural validity, convergence validity and discriminative validity) of the questionnaire.Results:A total of 850 questionnaires were collected, of which 614 were valid, with an effective response rate of 72.20%. The EFA resulted in the refinement of the rotavirus vaccine BeSD questionnaire from 37 to 35 items (including 24 core items), and suggested a five-factor structure including the perceptions of vaccine, confidence in vaccine, social process of vaccination, motivation for vaccination, and practical problems of vaccination. The cumulative variance contribution rate reached 56.27%. The CFA confirmed an ideal five-factor model fit (GFI=0.82,CFI=0.86,PNFI=0.67,RMSEA=0.07). The AVE of each dimension was greater than 0.50. The AVE square root of each dimension of the questionnaire was greater than its correlation coefficient. The Cronbach′s α coefficient of the total questionnaire was 0.79.Conclusion:The developed BeSD questionnaire of rotavirus vaccine has good reliability and validity, and can be used to measure parents′ behavioral and social factors in administering rotavirus vaccine to their children.

Objective:This study aimed to investigate the association between genetic factors and the risk of developing treatment-resistant depression (TRD), as well as the efficacy of modified electroconvulsive therapy (MECT), with a specific focus on identifying gene polymorphisms that can differentiate TRD from non-TRD.Methods:This case-control study included inpatients with depression in Adult Psychiatry Department, Affective Disorders Department and Geriatrics Department of Guangzhou Medical University Affiliated Brain Hospital from January 2023 to June 2024, as well as healthy individuals undergoing physical examinations in the outpatient department. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was utilized to genotype 16 loci across 10 candidate genes in 107 non-TRD patients, 101 TRD patients and 281 healthy controls. Hardy-Weinberg equilibrium testing, genotype frequency distribution analysis, and genetic association studies were conducted using PLINK software. Univariate binary logistic regression under a dominant model was performed using R software to analyze gene loci associated with non-TRD and TRD.Results:All 16 gene loci in the control group, the TRD group, and the non-TRD group were found to be in Hardy-Weinberg equilibrium ( P>0.05). No significant differences were observed in the genotype distribution of these gene loci across the groups ( P>0.05). Univariate binary logistic regression analysis revealed that individuals with depression carrying the HTR2A-rs7997012 G allele had a significantly lower risk of developing TRD ( OR=0.26, P=0.047). Among the patients receiving MECT, the proportion of G allele carriers who showed improvement at 2, 4, and 6 weeks of treatment was significantly higher compared to those who did not show improvement (96.61% vs. 80.95%, 96.55% vs. 50.00%, 96.59% vs. 46.15%, respectively), with χ2 values of 6.743, 29.295, and 32.300, respectively, and all P values <0.05. Conclusion:The HTR2A-rs7997012 polymorphism may represent a genetic distinction between TRD and non-TRD. Depressed patients with the rs7997012 G allele have a reduced likelihood of developing TRD, moreover, MECT demonstrates superior efficacy in this patient population.