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ObjectiveEvidence-based review of epidemiological change trends of Salmonella serotype infections in the United States in recent 50 years.MethodsTo collect and analyze 30 dominant Salmonella serotypes（including enteral and parenteral dominant serotypes） infected in humans and the ecologically dominant Salmonella serotypes in farmed animals （animal disease and non-animal disease groups） in the United States from 1968 to 2011， and analyze the big Salmonella serotypes data of National Enteric Salmonella Surveillance in the United States from 2006 to 2016. To correlate the Salmonella serotypes based on the outbreaks of Multistate foodborne and pet-borne disease in the United States from 2006 to 2017.ResultsThe United States has caused the formation of colonization and pathogenic ecological characteristics between some Salmonella serotypes and cultured animals based on the more and more developed breeding industry in the past 50 years. There is an exposure response relationship between the dominant Salmonella serotypes of colonized animals and the human infected. The long-term interaction between human and animal makes the dominant Salmonella serotypes highly match. In the past 50 years， the baseline of Salmonella infection in the population in the United States has been gradually increasing， The patients are most common in children and the elderly， the highest incidence in children under 1 year old， and more cases in the south and Midwest. In 2008， enteritis replaced typhimurium as the first human infection of Salmonella in the United States. The foods attributed to Salmonella multistate foodborne outbreaks have the consumption characteristics of transition from traditional meat， eggs， and milk to vegetables， ready-to-eat foods， fruits， etc. The Salmonella multistate pet-borne outbreaks， which have gradually increased since 2006 and are related to live animals such as domesticated reptiles， belong to behavioral ecotype infectious diseases， with longer duration， more dispersed cases and higher concealability than foodborne outbreaks.ConclusionTo summarizes the disease ecological characteristics of Salmonella in the United States， which can provide reference for the comprehensive prevention and control of salmonellosis between veterinarians and humans in China.

ObjectiveThis study aimed to analyze the serotype and phenotype of human and non-human sourced Salmonella from 1975 to 2021 in Fujian Province retrospectively.MethodsSalmonella isolates were collected from clinical hospitals， public service employee health， circulating fresh food， and the environment from 1975 to 2021 in Fujian Province， and serotypes and variants were distinguished using WHO-recommended Salmonella serotyping methods. Two prediction software were used based on whole genome sequencing， while the same antigen but different isolates or phenotypic variants were identified using biochemical combinations and MALDI-TOF-MS flight mass spectrometry.ResultsThere were 4 693 human- and non-human-sourced Salmonella isolates that contained 21 serogroups of four subspecies （18 from patients， 9 from healthy employees， 17 from food， and 8 from the environment）. Salmonella paratyphoid A， S. typhoid， S. enteritis， S. cholerae， S. typhimurium， S. rosen， and S. stanley were dominant isolates in the 30 total extraintestinal invasive serotypes. There were 96 Salmonella serotypes other than S. typhoid， S. paratyphoid A， and S. paratyphoid B （63 from patients， 51 from healthy employees， 60 from food， and 20 from the environment）， and the top 10 clinical serotypes were S. typhimurium， S. typhoid， S. enteritis， S. derby， S. stanley， S. paratyphoid A， S. anatum， S. wetavreden， S. rosen， and S. london， while the top 10 from food were S. anatum， S. derby， S. typhimurium， S. stanley， S. wetavreden， S. newport， S. enteritis， S. tompson， S. agona， and S. london. Fourteen serotypes （including 10 diphasic serotypes and 4 monophasic serotypes） had monophasic variants. Several serotypes had phenotypic variants such as hydrogen sulfide-negative， fermenter of lactose or sucrose， colony mucus type， and chromogenic type.ConclusionSalmonella are characterized by their biodiversity and multiple sources in Fujian Province. Invasive cases are gradually dominated by non-typhoid Salmonella. Laboratories should enhance their ability to diagnose monophasic variants and phenotypic variants of Salmonella， as well as pet and environmental traceability for scattered outbreaks of infectious diseases.

ObjectiveTo evaluate the equivalence of 5 Salmonella selective enrichment procedures in standard methods worldwide.MethodsThe growth rates（PR） and the colony characteristics of 5 selective enrichment broths（SC， TTB， RV， MKTTn， SBG） and 5 selective mediums（CAS， XLD， XLT4， HE， BS） were validated according to the GB4789.28—2013. The sensitivity（SE）， the relative trueness（RT） and the acceptable limit（AL） were estimated on highly contaminated foods through the use of 5 protocols combined with 5 selective enrichment broths and 2 selective mediums according to the method of ISO 16140—2：2016. The sensitivity（Se）， the specificity（Sp）， the positive predictive value（PPV） and the negative predictive value（NPV） were simultaneously determined through the use of 10 compound modes combined with selective enrichment broths and selective mediums according to the classical statistical methods.ResultsThe results showed that SC broth had no efficacy in enriching Salmonella enterica serotype Cholerae and Salmonella enterica serotype Cholerae var. Kunzendorf. The CAS and XLD were significantly better than XLT4， HE and BS in identifying typhoidal Salmonella and nontyphoidal Salmonella as well as the phenotype of hydrogen sulfide.Totally 84 samples（22 pieces of meat， 32 pieces of poultry and 30 pieces of aquatic products） were tested. 25 out of the 84（29.76%） were confirmed positive by 5 protocols， and 16 serotypes from 42 isolates were identified. The SE of 5 protocols were 84.00%， 100.00%， 88.00%，88.00% and 92.00%， respectively， but showed no statistically significant difference between each other. The AL of one protocol （SC+TTB） went beyond the limitation of the ISO 16140—2：2016 due to the ineffectiveness of SC broth. The compound mode of RV-CAS had the best comprehensive benefits， while the Se， the Sp， the PPV and the NPV of which were 68.00%， 95.00%， 85.00% and 88.00%， respectively.ConclusionThe ineffectiveness of SC broth reduces the sensitivity of the detection protocol for Salmonella， which could cause a negative deviation， resulting in the threshold exceeding of the Acceptability Limit （AL）. The combinational selective enrichment broth of RV-CAS is recommended to be the optimal mode， with CAS+XLD being recommended to be the optimal selective medium combination. The process of Salmonella serotyping is suggested to be improved in the standard of GB4789.4 to cope with the multi-serotype Salmonella contamination in food chain and be consistent with the international standardization for food microbiology.

ObjectiveTo investigate the genomic and virulence characteristics of seven invasive non-typhoidal Salmonella (iNTS) isolates.MethodsBased on the collection of seven iNTS strains, whole genome sequencing were performed. The serotypes, genomes and virulence factors were identified, annotated and analyzed according to the comparison of genome data and relevant databases.ResultsAmong the seven tested iNTS isolates, six were monophasic, including one Salmonella Typhimurium and two Salmonella I 4, [5], 12∶i∶-(ST34 type), two Salmonella Enteritidis, one Salmonella Corvallis and one unknown serotype with the antigenic formulae of I 4, [5], 12∶d∶- (ST279 type). No consistent rule was found in genomic components and relevant parameter differences varies much between different serotypes than those of the same serotype from different sources. The distribution of virulence factors (VF) was significantly different among different Salmonella serotypes, but the common VF characteristics in iNTS strains were not found, though Capsule/Immune evasion, toxin, peritrichous_flagella and Salmochelin may be associated with high invasiveness. All tested isolates contained type III and type VI secretion systems. The number of secretion protein, type III for S. Corvallis and type VI for Salmonella I 4, [5], 12∶d∶-was the highest among the seven isolates. Pseudogenization of the secreted effector SseI may exist among some Salmonella serotypes which may contribute to the enhancement of Salmonella invasiveness.ConclusionThe common characteristic differences of virulence factor between iNTS and gastroenteritis NTS were not observed at the moment, and highly invasive pathogenic mechanisms still require further analysis and research at the functional transcriptome and proteomic levels to determine the genetic basis of iNTS occurrence and transmission.

BACKGROUND: Pedicle screw internal fixation has been widely used in the lumbar spine, and fixed application in thoracic vertebra has gradually been accepted. Considering the narrow thoracic pedicle, especially at T3-T9. pedicle screw always punctures the cortex and important adjacent structures. To avoid serious complications, researchers developed the external pedicle approach from the costal transverse process joint and the costal vertebra joint to the vertebral body, and then others designed a similar screw entry method, which can provide enough safe paths as long as the ribs are not penetrated. At present, the existing studies mainly focus on the upper and middle thoracic vertebrae in adults. OBJECTIVE: To measure the anatomical parameters of pedicle-rib unit screw fixation in thoracic vertebrae of preschoolers, and to explore their developmental regularity and morphological characteristics at different age groups and sexes, so as to provide theoretical basis for clinical practice. METHODS: Sixty-seven preschoolers aged 7-12 years old without bone destruction, tumor, deformity, degeneration or fractures at the spine and no history of spine related surgery were selected. Three-dimensional reconstruction was conducted after spiral CT scanning. The morphological structure of pedicle-rib unit was observed. The transverse diameter, length, inclination angle and safety angle range of pedicle-rib unit screw were measured and analyzed statistically to investigate the feasibility of screw on anatomy. All guardians of the children signed the informed consents, and the study was approved by the hospital ethical committee. RESULTS AND CONCLUSION: (1) The transverse diameter of the thoracic pedicle-rib unit was increased with age, and decreased first and then increased with the increase of vertebral sequence. The transverse diameter in males was larger than in females at the same age. (2) The length of pedicle-rib screw channel was significantly different in different age groups (P < 0.05), which showed a significant increase with age and a trend of first increase and then decrease with the increase of vertebral sequence. (3) Pedicle-rib unit screw placement showed that safety angle range was 18°-25°, including maximum safety scope in T1, followed by T10, minimum in T4 and T5. (4) Thus, security angle range of pedicle-rib unit screw in children is narrower than that in adults. Compliance with the adult standards in screw placement may cause severe nerve damage to the nerves and blood vessels, so preoperative individualized screw placement should be carried out according to the CT results. [ABSTRACT FROM AUTHOR]

Objective: To investigate the infection status and virulent genes of Aeromonas in patients with acute diarrhea in Pudong New Area, Shanghai., Methods: In 2012, stool samples were collected from diarrhea patients in 12 sentinel hospitals in Pudong for the detections of 13 pathogens causing diarrhea, and the detections of 5 diarrhea related virulent genes were conducted for Aeromonas isolates., Results: A total of 101 patients were infected with Aeromonas in 2533 patients (4.0%). A total of 101 Aeromonas strains were isolated, including 17 Aeromonas hydrophila strains (18.8%), 44 Aeromonas veronii biovar sobria strains (52.5%) and 12 Aeromonas caviae strains (29.7%). And 44 coinfections with other pathogens were detected. Aeromonas infection mainly occurred in summer and in people aged ≥20 years. Among the patients infected with Aeromonas, 71 (70.3%) had watery diarrhea, 20 (19.8%) had vomiting and 11 (10.9%) had fever. Virulent genes detection showed that 95.0% of the Aeromonas. strains carried virulent genes, and the detection rates of hlyA, aerA, act, alt, and ast genes were 5.9%, 6.9%, 67.3%, 42.6% and 13.9%, respectively., Conclusions: High incidence of Aeromonas infection was found in the patients with acute diarrhea in Pudong, and a high proportion of coinfections with other pathogens was detected too. Most Aeromonas strains carried virulent genes, and the distribution varied.

Objective: To understand the distribution of diarrheagenic Escherichia (E.) coli in population in Shanghai and discuss the practice model of cooperation in enteric infectious disease prevention and control between public health institution and hospital., Methods: Sentinel hospitals were assigned, standard detection and identification of diarrheagenic E. coli were conducted, incidence curve of diarrheagenic E. coli infection was drawn and epidemiologic survey and laboratory detection were conducted for suspect diarrheagenic E. coli infection outbreaks., Results: A total of 7 204 stool specimens were collected from diarrhea patients in 4 hospitals during 2012-2013, in which 712 (9.9% ) were diarrheagenic E. coli positive, including 351 enteropathogenic E. coli (EPEC) strains, 292 enterotoxigenic E. coli (ETEC) strains, 32 enteroinvasive E. coli(EIEC) strains and 6 Shiga toxin-producing E. coli (STEC/EHEC) strains, as well as 31 mixed strains. EPEC infection mainly occurred in children aged 1-5 years; and all of these infections were caused by aEPEC. The incidence peak of ETEC infection was during August, the positive rate was >20%. The ETEC infection mainly occurred in infants aged 1-28 days in 2012 and in people aged 20-60 years in 2013 (P<0.05). ST was the major type (59.6%), followed by LT (27.8%) and ST/LT (12.6%). EIEC infection increased in children obviously in 2013 (P<0.01). No EHEC O157:H7 case was detected, but two EHEC O26:H11 (eae-hlyA-stx1a) cases in children were reported for the first time in Shanghai. The survey result indicated that the multidrug-resistant ETEC (STh-CS21-CFA/I-ClyA-EatA-ST2332-SHNL0005) strain causing outbreak in 15 newborns in Shanghai in 2012 was in the same clone as the strain detected in Zigong in Sichuan province., Conclusion: Significant change has occurred in diarrheagenic E. coli distribution in Shanghai in recent years, ETEC has potential risk to cause outbreak of hospital acquired infection in neonates and food borne infection. The active surveillance on ETEC and other enteric pathogens by both public health institutions and hospitals need to be improved.

Objective: To study the epidemiological characteristics and antibiotic resistance of Salmonella enterica serovar Pomona (S. Pomona)., Methods: Antimicrobial susceptible testing (AST) and pulsed field gel electrophoresis (PFGE) methods were used to analyze on S. Pomona strains that were isolated from diarrhea cases through the diarrhea network monitoring program, environment and food samples in Shanghai as well as from reptiles in Guangxi Zhuang Autonomous Region., Results: 4 553 clinic Salmonella (S.) strains were isolated from the Shanghai network laboratories from 2005 to 2012. The top 10 serotypes would include 20 serotypes all belonged to A-F groups, while S. Pomona was next to S. Wandsworth, according to the non- A-F groups. Young children seemed to be susceptible to S. Pomona, and might cause bloody stools and super-infection. The top 10 serotypes from 1 805 foodborne Salmonella strains were significantly more extensive than those from the human S. Pomona strains, followed by those rare serotypes which were mostly isolated from turtle, sea-shellfish and reptiles. Antibiotic resistance of S. Pomona strains from other sources were significantly more severe than those from human samples, and belonged to A and B clones by means of PFGE. Clone A strains were non-epidemic strains which showed multi-drug resistance (MDR) to antimicrobials. Clone B was the main epidemic-causing strain that not resistant to drugs, which consisting B- I from young-age-groups and B-II were from the seniors. B-I strains were homologous to those from shellfish, tortoises and lizards, while B-II strains only showing homology to those from shellfish. One S. Pomona strain-MDR, isolated from human was homologous to 8 antimicrobials., Conclusion: S. Pomona was a quite common serotype among those rare serotypes, which showed higher pathogenicity to infants while genetic evolution might take place when comparing them with the strains isolated from the clinics in 2005. Surveillance programs should be intensified along with the early warnings systems on infections which were from seafood and reptiles.