Objective Pathogens from the nosocomial infection have been analyzed by MALDI‐TOF microbial identification system ,to evaluate mass spectrometry analysis advantage and explore the mass spectrometry method .Methods The pathogens have been analyzed by MALDI‐TOF microbial identification system ,by compared with the VITEK‐2 compact detection in the tes‐ting time ,detection rate and the amounts of identified strains .The homology differences have been analyzed by comparison calcula‐tion of common peaks from the fingerprint spectrums .Results Thirty‐one Escherichia coli strains ,28 Klebsiella pneumonia strains and 9 unusual pathogen strains have been identified by MALDI‐TOF MS for only 1 hours .It has more advantages than VITEK‐2 in the testing time and other aspects .Conclusion Nosocomial infection of pathogen shows a point source propagation mode centering on the department .MALDI‐TOF mass spectrometry is able to rapidly and correctly identify the pathogen .MALDI‐TOF microbial i‐dentification system is expected to be the major detecting technique in the field of the pathogen monitor and resistance monitoring a ‐nalysis .

Objective: To analyze the epidemiological characteristics and genetic characteristics of sapovirus (SaV) in a cluster of schools in Changzhou, so as to provide a reference for the treatment of clustered vomiting and diarrhea events in schools. Methods: The epidemiological data and laboratory test data of sapovirus clusters in Changzhou from 2019 to 2022 were collected and analyzed. Partial VP1 genes of SaV positive samples were amplified and sequenced for phylogenetic analysis. Results: A total of 8 cases of clusters of SaV epidemics were reported in Changzhou City from 2019 to 2022, with 118 reported cases. The total attack rate was 1.47%, and the median of the attack number was 15. There were 6 outbreaks in kindergartens and 2 outbreaks in primary schools, which were reported in the epidemic period from September to December. The main clinical manifestations were vomiting (113 cases, 95.76 %), abdominal pain (39 cases, 33.05%), and diarrhea (16 cases, 13.56%). Among the 8 outbreaks, 17 sample strains were successfully sequenced. 5 outbreaks were GII.3 , and the other 3 outbreaks were GI.1, GI .3 and GII.2. GI and GII were the main genotypes in this area, and GII .3 was the predominant strain. Conclusion SaV is an important pathogen in the clusters of vomiting and diarrhea in schools after the transmission of norovirus. Continuous surveillance of SaV should be carried out to further understand its epidemiological characteristics and genotype distribution, so as to provide scientific basis for the prevention and control of the epidemic in schools.

Objective To probe into the feasibility and applicability of the foodborne food risk monitoring and sentinel hospital foodborne disease surveillance on the Salmonella serotype identification by liquid phase suspension array. Methods The serotyping of Salmonella isolates was performed by traditional glass agglutination test. Meanwhile, the liquid phase suspension array was operated to analyze the antigen O, H and AT for classification identification. Results From 2012 to 2019, a total of 215 strains of Salmonella were collected divided into 38 serotypes, 96% of them could be analyzed by SSA kit. The results of xMAP were in accordance with the traditional agglutination. 8 of the 11 strains which cannot be checked out by glass agglutination seemed to be easy detected by liquid phase suspension array. Conclusion The liquid phase suspension array has advantages of high throughput, high sensitivity and high specificity. It is able to detect the Salmonella serotype rapidly during a short time. Compared with the traditional serum agglutination method, the liquid phase suspension array has obvious advantages in detection time. It can be useful and important in the break out of foodborne disease caused by Salmonella spp.

Objective To analyze serotype distribution, drug resistance, quinolone resistance gene carrying status and genetic relationship of foodborne Salmonella and human Salmonella isolates in Changzhou from 2012 to 2018, to provide scientific basis for the prevention and control of Salmonella. Methods The serum type was identified by serum agglutination and liquid chip. The antibiotic sensitivity was determined by micro broth dilution method. The quinolone antibiotic resistance gene was determined by gene sequencing method. The multilocus sequence typing ( MLST ) typing was performed on quinolone-resistant Salmonella, and the genetic relationship was analyzed by BioNumerics 8.0. Results A total of 10 and 36 serotypes were detected in 46 foodborne Salmonella strains and 152 human Salmonella strains, respectively. The dominant serotypes were Indiana Salmonella and Salmonella typhimurium. Erythromycin resistance rate was the highest in both Salmonella strains, and the proportion of multidrug-resistant bacteria was 93.47 % ( 43 / 46 ) and 80.92 % ( 123 / 152 ), respectively. 38 strains of quinolone-resistant foodborne Salmonella GyrA subunit mainly occurred double mutations Asp87Asn, Ser83Phe, ParC subunit mainly occurred single mutation Ser80Arg, 119 strains of quinolone-resistant human Salmonella qnrS gene detection rate was higher, reached 68.1 % ( 81 / 119 ) ; The dominant ST types of quinolone-resistant Salmonella from two sources were ST17 and ST19, respectively. Conclusions The antibiotic sensitivity of the two Salmonella resistant strains from Changzhou was the same ; Synergistic drug resistance, but both quinolone resistance genemutations and carry inconsistent ; The ST type distribution of quinolone resistant strains isalso inconsistent, and the genetic relationship is far. It is suggested that the probability of Salmonella resistant bacteria infection caused by food transmission in our region is small, and the treatment of the two should be differentiated.