Objective: Using Meta-analysis to evaluate the vaccine effectiveness of 13-valent pneumococcal conjugate vaccine (PCV13) against invasive Streptococcus pneumoniae disease (IPD) caused by serotype 19A in children <5 years old. Methods: "Streptococcus pneumoniae infection""invasive pneumococcal disease""13-valent pneumococcal polysaccharide conjugate vaccine""PCV13""effectiveness""infant""child" and related terms were searched from China National Knowledge Infrastructure (CNKI), WANFANG DATA, PubMed, SCOPUS and Web of science with no limited on language, region and research institution. The retrieval time was limited from January 2010 to February 2023 and cohort study, case-control study and randomized controlled trial were included. Data were extracted from eligible studies by two independent reviewers, and after study quality assessment by NOS scale, Meta-analysis was completed using Stata 16.0 software. Results: A total of 2 340 related literatures were searched, and 10 literatures were finally included, including 5 case-control studies and 5 indirect cohort studies, which showed good literature quality. The vaccine effectiveness against serotype 19A IPD of PCV13 in children was 83.91% (95%CI: 78.92%-88.89%), and the subgroup analysis (P=0.240) showed there was no significant difference among the case-control study (VE=87.34%, 95%CI:79.74%-94.94%) and the indirect cohort study (VE=81.30%, 95%CI:74.69%-87.92%). The funnel plot and Egger test suggested that the possibility of publication bias was small. Conclusion: The present evidence indicates that PCV13 has a good vaccine effectiveness against serotype 19A IPD in children, and it is recommended to further increase the vaccination rate of PCV13 to reduce the disease burden of IPD in children <5 years old.
Child ; Humans ; Child, Preschool ; Case-Control Studies ; Cohort Studies ; Serogroup ; Vaccines, Conjugate/therapeutic use* ; China ; Pneumococcal Infections/prevention & control*

Objective: Using Meta-analysis to evaluate the vaccine effectiveness of 13-valent pneumococcal conjugate vaccine (PCV13) against invasive Streptococcus pneumoniae disease (IPD) caused by serotype 19A in children <5 years old. Methods: "Streptococcus pneumoniae infection""invasive pneumococcal disease""13-valent pneumococcal polysaccharide conjugate vaccine""PCV13""effectiveness""infant""child" and related terms were searched from China National Knowledge Infrastructure (CNKI), WANFANG DATA, PubMed, SCOPUS and Web of science with no limited on language, region and research institution. The retrieval time was limited from January 2010 to February 2023 and cohort study, case-control study and randomized controlled trial were included. Data were extracted from eligible studies by two independent reviewers, and after study quality assessment by NOS scale, Meta-analysis was completed using Stata 16.0 software. Results: A total of 2 340 related literatures were searched, and 10 literatures were finally included, including 5 case-control studies and 5 indirect cohort studies, which showed good literature quality. The vaccine effectiveness against serotype 19A IPD of PCV13 in children was 83.91% (95%CI: 78.92%-88.89%), and the subgroup analysis (P=0.240) showed there was no significant difference among the case-control study (VE=87.34%, 95%CI:79.74%-94.94%) and the indirect cohort study (VE=81.30%, 95%CI:74.69%-87.92%). The funnel plot and Egger test suggested that the possibility of publication bias was small. Conclusion: The present evidence indicates that PCV13 has a good vaccine effectiveness against serotype 19A IPD in children, and it is recommended to further increase the vaccination rate of PCV13 to reduce the disease burden of IPD in children <5 years old.
Child ; Humans ; Child, Preschool ; Case-Control Studies ; Cohort Studies ; Serogroup ; Vaccines, Conjugate/therapeutic use* ; China ; Pneumococcal Infections/prevention & control*

OBJECTIVE: To establish and modify quantitative real-time polymerase chain reaction (qPCR)-based serotyping assays to distinguish 97 pneumococcal serotypes. METHODS: A database of capsular polysaccharide ( cps) loci sequences was generated, covering 97 pneumococcal serotypes. Bioinformatics analyses were performed to identify the cps loci structure and target genes related to different pneumococcal serotypes with specific SNPs. A total of 27 novel qPCR serotyping assay primers and probes were established based on qPCR, while 27 recombinant plasmids containing serotype-specific DNA sequence fragments were constructed as reference target sequences to examine the specificity and sensitivity of the qPCR assay. A panel of pneumococcal reference strains was employed to evaluate the capability of pneumococcal serotyping. RESULTS: A total of 97 pneumococcal serotyping assays based on qPCR were established and modified, which included 64 serotypes previously reported as well as an additional 33 serotypes. Twenty-seven novel qPCR serotyping target sequences were implemented in the pneumococcal qPCR serotyping system. A total of 97 pneumococcal serotypes, which included 52 individual serotypes and 45 serotypes belonging to 20 serogroups, could not be identified as individual serotypes. The sensitivity of qPCR assays based on 27 target sequences was 1-100 copies/µL. The specificity of the qPCR assays was 100%, which were tested by a panel of 90 serotypes of the pneumococcal reference strains. CONCLUSION A total of 27 novel qPCR assays were established and modified to analyze 97 pneumococcal serotypes.
Real-Time Polymerase Chain Reaction ; Serotyping ; Streptococcus pneumoniae/genetics* ; Serogroup

OBJECTIVES: To investigate the potential relationship between age and Streptococcus pneumoniae vaccination coverage in kindergarten children, and to provide a basis for guiding vaccination and developing new protein vaccines. METHODS: The stratified cluster random sampling method was used to select 1 830 healthy children from six kindergartens in Shunde District, Foshan City, China, and nasopharyngeal swabs were collected for the isolation and identification of Streptococcus pneumoniae. The logistic regression model based on restricted cubic spline was used to analyze the dose-response relationship between age and Streptococcus pneumoniae vaccination coverage. RESULTS: The rate of nasal Streptococcus pneumoniae carriage was 22.46% (411/1 830) among the kindergarten children, with the predominant serotypes of 6B, 19F, 15A, 23A, 34, and 23F. The coverage rates of 10-valent pneumococcal conjugate vaccine (PCV10) and 13-valent pneumococcal conjugate vaccine (PCV13) were 53.0% and 57.9%, respectively, and there was a significant non-linear dose-response relationship between age and the coverage rates of PCV10 and PCV13 (P<0.05), with a higher coverage rate of PCV10 (88.0%) and PCV13 (91.1%) in the children aged 2 years. There was a significant non-linear dose-response relationship between age and the coverage rates of pilus islet 1 (PI-1) and pilus islet 2 (PI-2) (P<0.05), with a lower vaccination coverage rate for PI-1 (37.7%) and PI-2 (16.1%). The coverage rates of PI-1 (13.0%-58.5%) and PI-2 (6.0%-29.4%) were lower in all age groups. The virulence genes lytA (99.5%) and ply (99.0%) associated with candidate protein vaccines showed higher vaccination coverage rates. CONCLUSIONS There is a significant non-linear dose-response relationship between the age of kindergarten children and the coverage rates of PCV10 and PCV13 serotypes, and kindergarten children aged 2 years have a relatively high coverage rate of PCV. The high prevalence of the virulence genes lytA and ply shows that they are expected to become candidate virulence factors for the development of a new generation of recombinant protein vaccines.
Humans ; Child ; Infant ; Streptococcus pneumoniae/genetics* ; Pneumococcal Infections/epidemiology* ; Vaccination Coverage ; Pneumococcal Vaccines ; Serogroup ; Vaccination ; Nasopharynx ; Carrier State/epidemiology*

Objective: To characterize the prevalence and genomic epidemiology of Vibrio parahaemolyticus from acute diarrheal patients in Shenzhen City from 2013 to 2021. Methods: Based on the Shenzhen Infectious Diarrhea Surveillance System, acute diarrheal patients were actively monitored in sentinel hospitals from 2013 to 2021. Whole-genome sequencing (WGS) of Vibrio parahaemolyticus isolates was performed, and the genomic population structure, serotypes, virulence genes and multilocus sequence typing were analyzed. Outbreak clusters from 2019 to 2021 were explored based on single-nucleotide polymorphism analysis. Results: A total of 48 623 acute diarrhea cases were monitored in 15 sentinel hospitals from 2013 to 2021, and 1 135 Vibrio parahaemolyticus strains were isolated, with a positive isolation rate of 2.3%. Qualified whole-genome sequencing data of 852 isolates were obtained. Eighty-nine serotypes, 21 known ST types and 5 new ST types were identified by sequence analysis, and 93.2% of strains were detected with toxin profile of tdh+trh-. 8 clonal groups (CGs) were captured, with CG3 as the absolute predominance, followed by CG189. The CG3 group was dominated by O3:K6 serotype and ST3 sequence type, while CG189 group was mainly O4:KUT, O4:K8 serotypes and ST189a and ST189 type. A total of 13 clusters were identified, containing 154 cases. About 30 outbreak clusters with 29 outbreak clusters caused by CG3 strains from 2019 to 2021. Conclusion: Vibrio parahaemolyticus is a major pathogen of acute infectious diarrhea in Shenzhen City, with diverse population structures. CG3 and CG189 have been prevalent and predominant in Shenzhen City for a long time. Scattered outbreaks and persistent sources of contamination ignored by traditional methods could be captured by WGS analysis. Tracing the source of epidemic clone groups and taking precise prevention and control measures are expected to significantly reduce the burden of diarrhea diseases caused by Vibrio parahaemolyticus infection in Shenzhen City.
Humans ; Vibrio parahaemolyticus/genetics* ; Diarrhea/epidemiology* ; Foodborne Diseases/epidemiology* ; Serogroup ; Genomics ; Dysentery ; Vibrio Infections/epidemiology* ; Serotyping

OBJECTIVE: Melittin, a cell-penetrating peptide, improves the efficiency of many non-viral gene delivery vectors, yet its application in viral vectors has not been well studied. The non-pathogenic recombinant adeno-associated virus (rAAV) vector is an ideal in vivo gene delivery vector. However, its full potential will only be achieved after improvement of its transduction efficiency. To improve the transduction efficiency of rAAV2 vectors, we attempted to develop a melittin-based rAAV2 vector delivery strategy. METHODS: The melittin peptide was inserted into the rAAV2 capsid either in the loop VIII of all viral proteins (VPs) or at the N terminus of VP2. Various rAAV2-gfp or -fluc vectors were subjected to quantitative real-time polymerase chain reaction and Western blot assays to determine their titers and integrity of capsid proteins, respectively. Alternatively, the vectors based on wild-type capsid were pre-incubated with melittin, followed by transduction of cultured cells or tail vein administration of the mixture to C57BL/6 and BALB/c nude mice. In vivo bioluminescence imaging was performed to evaluate the transgene expression. RESULTS: rAAV2 vectors with melittin peptide inserted in the loop VIII of VPs had low transduction efficiency, probably due to dramatically reduced ability to bind to the target cells. Fusing the melittin peptide at the N-terminus of VP2 produced vectors without the VP2 subunit. Interestingly, among the commonly used rAAV vectors, pre-incubation of rAAV2 and rAAV6 vectors with melittin significantly enhanced their transduction efficiency in HEK293 and Huh7 cells in vitro. Melittin also had the ability to increase the rAAV2-mediated transgene expression in mouse liver in vivo. Mechanistically, melittin did not change the vector-receptor interaction. Moreover, cell counting kit-8 assays of cultured cells and serum transaminase levels indicated melittin had little cytotoxicity. CONCLUSION Pre-incubation with melittin, but not insertion of melittin into the rAAV2 capsid, significantly enhanced rAAV2-mediated transgene expression. Although further in vivo evaluations are required, this research not only expands the pharmacological potential of melittin, but also provides a new strategy to improve gene therapy mediated by rAAV vectors.
Mice ; Animals ; Humans ; Melitten/genetics* ; Dependovirus/genetics* ; Serogroup ; HEK293 Cells ; Mice, Nude ; Mice, Inbred C57BL ; Transgenes ; Genetic Vectors/genetics*

Objective: To analyze the drug resistance and genomic characteristics of Salmonella enterica serovar London isolated from clinical and food sources in Hangzhou City from 2017 to 2021. Methods: A total of 91 Salmonella enterica serovar London strains isolated from Hangzhou City from 2017 to 2021 were analyzed for drug susceptibility, pulsed field gel electrophoresis (PFGE) typing and whole genome sequencing. Multilocus sequence typing (MLST), core genome multilocus sequence typing (cgMLST) and detection of drug resistance genes were performed by using the sequencing data. Phylogenetic analysis was conducted to compare the 91 genomes from Hangzhou City with 347 genomes from public databases. Results: No significant difference in the drug resistance rate was observed between clinical strains and food strains to 18 drugs in Hangzhou City(all P>0.05), and the multidrug resistance (MDR) rate was 75.8% (69/91). Most strains were resistant to 7 drug classes simultaneously. One strain was resistant to Polymyxin E as well as positive for mcr-1.1, and 50.5% (46/91) of the strains were resistant to Azithromycin and were positive for mph(A). All 91 Salmonella enterica serovar London strains were ST155, which were subdivided into 44 molecular types by PFGE and 82 types by cgMLST. Phylogenetic analysis showed that most strains from Hangzhou City (83/91) were clustered together, and a small number of human isolates from Europe, North America and pork isolates from Hubei and Shenzhen were mixed in the cluster. Other strains from Hangzhou City (8/91) were closely related to strains from Europe, America and Southeast Asia. Strains isolated from pork were the most closely related to clinical strains. Conclusion: The epidemic of Salmonella enterica serovar London in Hangzhou City is mainly caused by the spread of ST155 strains, which is mainly transmitted locally. At the same time, cross-region transmission to Europe, North America, Southeast Asia, and other provinces and cities in China may also occur. There is no significant difference in the drug resistance rate between clinical strains and food strains, and a high level of MDR is found in the strains. Clinical infection of Salmonella enterica serovar London may be closely related to pork consumption in Hangzhou City.
Humans ; Salmonella enterica/genetics* ; Serogroup ; Anti-Bacterial Agents/pharmacology* ; Multilocus Sequence Typing ; Cities ; London ; Clonidine ; Phylogeny ; Genomics ; Drug Resistance ; Electrophoresis, Gel, Pulsed-Field ; Microbial Sensitivity Tests

Epidemic cerebrospinal meningitis (meningococcal meningitis) is an acute respiratory infectious disease with high mortality and serious sequelae. Meningococcal vaccine is an effective measure to prevent and control meningococcal meningitis. At present, group B meningococcal meningitis has become the main prevalent serum group in the world, including China. Meningococcal ACYW and other vaccines are mainly composed of capsular polysaccharides, while the main component of group B meningococcal vaccine is protein, including outer membrane vesicles (OMV) and recombinant protein vaccine. The methods for evaluating the immunogenicity of group B meningococcal vaccine include hSBA and alternative methods such as meningococcal antigen typing system (MATS), flow cytometric meningococcal antigen surface expression assay (MEASURE), genetic meningococcal antigen typing system (gMATS) and bexsero antigen sequence type (BAST). The evaluation of vaccine immunogenicity is the basis of vaccine development and clinical trial research, However, at present, there is no group B meningococcal vaccine in China. Therefore, in this paper, the research progress of immunogenicity evaluation of group B meningococcal vaccine has been reviewed, in order to provide technical guidance for the research and development of group B meningococcal vaccine, immunogenicity evaluation and clinical trial research in China.
Humans ; Meningitis, Meningococcal/prevention & control* ; Meningococcal Vaccines ; Neisseria meningitidis ; Serogroup ; Vaccines, Combined

Two cases of epidemic situation of serogroup B meningitis in infants in Shandong Province in 2021 were investigated. Samples of cases and their close contacts were collected for isolation, culture and identification of Neisseria meningitides (Nm). The isolates were subjected to multi-locus sequence typing, outer membrane protein porA and fetA genotyping and drug sensitivity test. Two laboratory-confirmed outbreaks of serogroup B meningitis were reported from Yantai city and Linyi city. The indicated cases were infants aged 5 months and 2 months old respectively. They were not vaccinated with meningitis vaccine. Their epidemiological characteristics and clinical manifestations were similar and the prognosis was good. The same sequence type (ST) of serogroup B Nm strains as the indicated cases was detected in the samples of close family contacts, but without subsequent cases. Among them, Yantai strain was were identified as the type ST-8920, belonging to CC4821 clonal complex, and the genotypes of porA and fetA were p1.21-2, 23 and F3-1. Linyi strain was a new type, belonging to CC4821 clonal complex and the genotypes of porA and fetA were p1.20, 23 and F1-91. The above strains were resistant to penicillin, ciprofloxacin, levofloxacin and Chemitrim, and their sensitivity to cephalosporin decreased. Two cases of infant serogroup B epidemic were relatively rare in China, which were different from the epidemiological and pathogenic characteristics of other Nm serogroups in the past.
Epidemics ; Humans ; Infant ; Meningitis, Meningococcal/epidemiology* ; Multilocus Sequence Typing ; Neisseria meningitidis ; Serogroup

Objective: To analyze the incidence of leptospirosis in Fujian province from 2015 to 2020 and provide the scientific evidences for the risk assessment, prevention and control of leptospirosis. Methods: The incidence data of leptospirosis in Fujian during 2015-2020 were collected from China Information System for Disease Control and Prevention for a descriptive analysis, and software ArcGIS 10.3.1 was used for spatial autocorrelation analysis, and rats were captured in 17 surveillance areas during the same period, and the rat organs were collected for pathogen culture, the level of Leptospira antibody was detected in serum samples of rats, healthy population and the serum samples of patients sent by the hospitals. The infection status of Leptospira in human and rats were analyzed. Results: The incidence of leptospirosis in Fujian showed a downward trend from 2015 to 2020. A total of 176 cases of leptospirosis were reported. There were obvious seasonality and bimodal distribution. The majority of cases were farmers, accounting for 49.43% (87/176). Most cases were aged 30-69 years (85.80%, 151/176). The male to female ratio of the cases was 3.51∶1 (137∶39). Spatial autocorrelation analysis showed that leptospirosis had high or low clustering areas. From 2015 to 2020, the average capture rate of rats in 17 surveillance areas was 6.96% (1 519/21 838), Rattus losea, Rattus flavipectus and Niviventer fulvescens were the main species. The average positive rate of Leptospira antibody in rats was 28.64% (252/880). Java and Autumnalis were the predominant serogroups, accounting for 56.75% (143/252) and 17.46% (44/252), respectively. The average positive rate of Leptospira antibody in healthy population was 16.13% (254/1 575), and Autumnalis and Australis were the predominant serogroups, accounting for 71.65% (182/254). The confirmation rate of leptospirosis in patient serum samples sent by the hospitals was 2.23% (188/8 431), Autumnalis (56.38%, 106/188) and Hebdomadis (19.68%, 37/188) were the major serogroups. Conclusions: The incidence of leptospirosis in Fujian showed a downward trend from 2015 to 2020, there were obvious area clustering and seasonality. The high clustering areas were mainly distributed in northern, western and central Fujian. Java and Autumnalis were the predominant serogroups in rats. The infection rate in healthy population decreased year by year. Autumnalis and Hebdomadis were the main serogroups in population in Fujian.
Animals ; Antibodies, Bacterial ; Female ; Humans ; Incidence ; Leptospira ; Leptospirosis/epidemiology* ; Male ; Rats ; Serogroup