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ObjectiveTo determine the pathogen and phylogenetic characteristics of an uncommon outbreak of recombinant norovirus infection in Daishan County in February 2022.MethodsFluorescence quantitative PCR was used to detect the norovirus in the eight anal swabs collected in the outbreak. In the positive samples， reverse transcription PCR were used to amplify the norovirus. Norovirus sequences were characterized by MEGA7 and Simplot.ResultsNorovirus GⅠ was identified in all eight anal samples. It was further determined to be recombinant norovirus GⅠ.6 ［P11］， with the recombination site at the ORF1-ORF2 junction. The sequence had the highest nucleotide identity （98.75%） to a GⅠ.6［P11］ strain collected in 2018 （GenBank accession number MT357995）.ConclusionAccording to the etiological identification and phylogenetic analysis， this outbreak is confirmed to be caused by the uncommon recombinant norovirus GⅠ.6 ［P11］ in China.

Objective: To investigate the epidemic factors of hemorrhagic fever with renal syndrome (HFRS) and compare the S and M gene sequences of hantavirus (HV) between rodents and the infected cases. Methods: Detailed epidemiological investigations were conducted on the cases' working and living areas. Captured rodents were classified by night trapping method, and their lungs and blood were collected for virus carriage detection after aseptic dissection. Viral S and M fragments of HV RNA were amplified and sequenced from positive samples of cases and mice, and their homology was analyzed. Results: After reconstruction, the geographic and living environment changed significantly, altering rodent behaviors. The industrial park, characterized by high population density, poor living conditions, and frequent contact of rodent (feces) and humans, had a high rodent density and HV virus infection ratio. Four workers infected with HV were positive for anti-HV immunoglobulin G (IgG) and IgM. Among the positive samples, HV RNA was detected in all two cases, and four Rattus norvegicus specimens were Seoul type HV S3 subtype. The virus had the closest relationship with Rod/2012/QHD/4/Gc (Hebei, China) and RuianRn180 (Zhejiang, China), with the 100% homology of M gene segment. The homology of viral S gene segment exhibited the closest relationship with the Jiangxi isolated JiangxiXinjianRn-09–2011, ranging from 99.6% to 99.8%. Conclusion: The HV sequencing showed a strong epidemiological relationship between the cases and host rodents. Improving living environmental health conditions, administering HFRS vaccine, and reducing rodent density and human–rodent contact can mitigate the risk of HFRS. [ABSTRACT FROM AUTHOR]