Objective This study reports the first imported case of Lassa fever(LF)in China.Laboratory detection and molecular epidemiological analysis of the Lassa virus(LASV)from this case offer valuable insights for the preven...Objective This study reports the first imported case of Lassa fever(LF)in China.Laboratory detection and molecular epidemiological analysis of the Lassa virus(LASV)from this case offer valuable insights for the prevention and control of LF.Methods Samples of cerebrospinal fluid(CSF),blood,urine,saliva,and environmental materials were collected from the patient and their close contacts for LASV nucleotide detection.Whole-genome sequencing was performed on positive samples to analyze the genetic characteristics of the virus.Results LASV was detected in the patient’s CSF,blood,and urine,while all samples from close contacts and the environment tested negative.The virus belongs to the lineage IV strain and shares the highest homology with strains from Sierra Leone.The variability in the glycoprotein complex(GPC)among different strains ranged from 3.9%to 15.1%,higher than previously reported for the seven known lineages.Amino acid mutation analysis revealed multiple mutations within the GPC immunogenic epitopes,increasing strain diversity and potentially impacting immune response.Conclusion The case was confirmed through nucleotide detection,with no evidence of secondary transmission or viral spread.The LASV strain identified belongs to lineage IV,with broader GPC variability than previously reported.Mutations in the immune-related sites of GPC may affect immune responses,necessitating heightened vigilance regarding the virus.展开更多
Introduction:In April 2025,three suspected human cases of avian influenza were identified in Changsha,China.Laboratory testing confirmed three cases of H9N2 AIV infection.This report summarizes the epidemiological fin...Introduction:In April 2025,three suspected human cases of avian influenza were identified in Changsha,China.Laboratory testing confirmed three cases of H9N2 AIV infection.This report summarizes the epidemiological findings from cases and contact investigations,along with genetic characterization of the isolated H9N2 strains.Methods:Comprehensive epidemiological assessments were conducted for each confirmed case.Virus isolation and culture were performed using throat swab specimens obtained from the cases.Isolated H9N2 strains were sequenced using nextgeneration sequencing(NGS).HA and NA gene sequences were analyzed for homology;evolutionary trees were constructed;and key antigenic sites were examined to identify genetic features.Results:All three cases were sporadic.No influenzalike illness was observed among close contacts or live poultry store employees during the 10-day medical monitoring period.Phylogenetic analysis indicated that the HA gene of all three H9N2 strains belonged to the A/Duck/Hong Kong/Y280/97(Y280-like)clade within the Eurasian lineage.HA gene sequence homology was 99.7%–99.8%,and NA gene homology was 98.4%–99.8%.The HA protein cleavage site was identified as PSRSSR↓GLF.Several HA protein site mutations were detected—H191N,A198T/V,Q226L,and Q234L—that had been previously associated with increased binding to receptors.HA-232H,234L,and 236G support a binding preference for the human-type sialic acid-α-2,6-galactose receptors.Conclusion:All three H9N2 avian influenza cases were mild and involved reported exposure to poultry or related environments.Genetic analysis revealed high homology of HA and NA among the isolated viruses.No epidemiological links were identified between cases,and no evidence was found of sustained humanto-human transmission.Continued avian influenza surveillance and public health education are warranted.展开更多
Introduction:On September 16,2024,the Puyang City CDC received a report of a suspected foodborne disease outbreak involving 14 individuals who developed nausea,vomiting,and diarrhea following attendance at a hotel ban...Introduction:On September 16,2024,the Puyang City CDC received a report of a suspected foodborne disease outbreak involving 14 individuals who developed nausea,vomiting,and diarrhea following attendance at a hotel banquet.Upon notification,the District CDC immediately deployed a specialized investigation team to characterize the epidemiological features of the outbreak,identify the causative pathogen,assess potential transmission risks,and implement effective control and prevention measures.Methods:We integrated comprehensive on-site epidemiological investigations,clinical symptom analyses,and laboratory diagnostics to isolate and identify pathogenic agents from retained food samples,environmental specimens,and anal swabs collected from affected cases.The recovered isolates underwent enterotoxin-virulence-gene profiling,antimicrobialsusceptibility testing,and phylogenetic analyses.Additionally,we characterized the architecture of the enterotoxin-A-linked pathogenicity island vSaβ.Results:A total of 4 S.aureus strains were successfully isolated from 22 leftover food samples,2 environmental swabs,and 2 patient anal swabs.Contaminated donkey and goose meat was identified as the outbreak source.All isolates harbored sea and seb enterotoxin genes,exhibited PEN-OXA-ERY-CLI resistance patterns,and were identified as clonal ST59-spa t441-SCCmec IVa CA-MRSA strains.Phylogenetic analysis positioned the outbreak strains within the Asia-Pacific clade,distinguishing them from the North American ST59 sublineage.Comprehensive analysis of the sea-associated virulence island vSaβidentified a novel structural arrangement containing a type A IEC cluster(sea-sak-chp-scn).Conclusions:The detection of foodborne ST59 CAMRSA clones in this outbreak underscores the prevalence and transmission risks associated with this hypervirulent lineage.These findings emphasize the critical need to strengthen surveillance measures for CA-MRSA among food industry workers.展开更多
基金supported by Public Health Talent Training and Surport Plan(National Administration of Disease Prevention and Control)Research and application of new technology for rapid monitoring and tracing of emergent infectious diseases among entry-exit population(2024YFFK0056)Monitoring,Early warning and Response of Major Infectious Diseases(2022ZDZX0017).
文摘Objective This study reports the first imported case of Lassa fever(LF)in China.Laboratory detection and molecular epidemiological analysis of the Lassa virus(LASV)from this case offer valuable insights for the prevention and control of LF.Methods Samples of cerebrospinal fluid(CSF),blood,urine,saliva,and environmental materials were collected from the patient and their close contacts for LASV nucleotide detection.Whole-genome sequencing was performed on positive samples to analyze the genetic characteristics of the virus.Results LASV was detected in the patient’s CSF,blood,and urine,while all samples from close contacts and the environment tested negative.The virus belongs to the lineage IV strain and shares the highest homology with strains from Sierra Leone.The variability in the glycoprotein complex(GPC)among different strains ranged from 3.9%to 15.1%,higher than previously reported for the seven known lineages.Amino acid mutation analysis revealed multiple mutations within the GPC immunogenic epitopes,increasing strain diversity and potentially impacting immune response.Conclusion The case was confirmed through nucleotide detection,with no evidence of secondary transmission or viral spread.The LASV strain identified belongs to lineage IV,with broader GPC variability than previously reported.Mutations in the immune-related sites of GPC may affect immune responses,necessitating heightened vigilance regarding the virus.
基金Supported by grants from Hunan Provincial Health Commission Major Scientific Research Program for High-Level Health Talents(R2023067)Central Guidance on Local Science and Technology Development Fund of Hunan Province(2024ZYC031-5)+1 种基金Scientific Research Project of Hunan Provincial Health Commission(A202312066016,D202312069067)Hunan Provincial Center for Disease Control and Prevention Qinghe Foundation(QHJJ2024001).
文摘Introduction:In April 2025,three suspected human cases of avian influenza were identified in Changsha,China.Laboratory testing confirmed three cases of H9N2 AIV infection.This report summarizes the epidemiological findings from cases and contact investigations,along with genetic characterization of the isolated H9N2 strains.Methods:Comprehensive epidemiological assessments were conducted for each confirmed case.Virus isolation and culture were performed using throat swab specimens obtained from the cases.Isolated H9N2 strains were sequenced using nextgeneration sequencing(NGS).HA and NA gene sequences were analyzed for homology;evolutionary trees were constructed;and key antigenic sites were examined to identify genetic features.Results:All three cases were sporadic.No influenzalike illness was observed among close contacts or live poultry store employees during the 10-day medical monitoring period.Phylogenetic analysis indicated that the HA gene of all three H9N2 strains belonged to the A/Duck/Hong Kong/Y280/97(Y280-like)clade within the Eurasian lineage.HA gene sequence homology was 99.7%–99.8%,and NA gene homology was 98.4%–99.8%.The HA protein cleavage site was identified as PSRSSR↓GLF.Several HA protein site mutations were detected—H191N,A198T/V,Q226L,and Q234L—that had been previously associated with increased binding to receptors.HA-232H,234L,and 236G support a binding preference for the human-type sialic acid-α-2,6-galactose receptors.Conclusion:All three H9N2 avian influenza cases were mild and involved reported exposure to poultry or related environments.Genetic analysis revealed high homology of HA and NA among the isolated viruses.No epidemiological links were identified between cases,and no evidence was found of sustained humanto-human transmission.Continued avian influenza surveillance and public health education are warranted.
文摘Introduction:On September 16,2024,the Puyang City CDC received a report of a suspected foodborne disease outbreak involving 14 individuals who developed nausea,vomiting,and diarrhea following attendance at a hotel banquet.Upon notification,the District CDC immediately deployed a specialized investigation team to characterize the epidemiological features of the outbreak,identify the causative pathogen,assess potential transmission risks,and implement effective control and prevention measures.Methods:We integrated comprehensive on-site epidemiological investigations,clinical symptom analyses,and laboratory diagnostics to isolate and identify pathogenic agents from retained food samples,environmental specimens,and anal swabs collected from affected cases.The recovered isolates underwent enterotoxin-virulence-gene profiling,antimicrobialsusceptibility testing,and phylogenetic analyses.Additionally,we characterized the architecture of the enterotoxin-A-linked pathogenicity island vSaβ.Results:A total of 4 S.aureus strains were successfully isolated from 22 leftover food samples,2 environmental swabs,and 2 patient anal swabs.Contaminated donkey and goose meat was identified as the outbreak source.All isolates harbored sea and seb enterotoxin genes,exhibited PEN-OXA-ERY-CLI resistance patterns,and were identified as clonal ST59-spa t441-SCCmec IVa CA-MRSA strains.Phylogenetic analysis positioned the outbreak strains within the Asia-Pacific clade,distinguishing them from the North American ST59 sublineage.Comprehensive analysis of the sea-associated virulence island vSaβidentified a novel structural arrangement containing a type A IEC cluster(sea-sak-chp-scn).Conclusions:The detection of foodborne ST59 CAMRSA clones in this outbreak underscores the prevalence and transmission risks associated with this hypervirulent lineage.These findings emphasize the critical need to strengthen surveillance measures for CA-MRSA among food industry workers.
