This study investigated the potential pathogenicity and genetic characteristics of ST314 Salmonella Kentucky(S.Ken-tucky)isolates from a broiler slaughterhouse.Antimicrobial susceptibility testing and whole-genome sequencing(WGS)were used to determine antimicrobial resistance,virulence factors,and the presence of antimicrobial resistance genes(ARGs)and mobile genetic elements(MGEs)among the isolates.The three multidrug resistant(MDR)isolates exhibited high resistance to multiple antimicrobial agents.The F4-2S strain exhibited resistance to 14 drugs across seven categories,whereas the F4T strain showed resistance to 13 drugs in the same number of categories.In contrast,the Y23 strain was resistant to nine drugs in six categories.Notably,F4-2S dem-onstrated high homology with F4T:both possessed 13 ARGs distributed across nine categories,in addition to a wide range of virulence factors,including secretion systems and effector proteins.The presence of IncR and IncX1 plasmids significantly enhanced both the antimicrobial resistance and pathogenicity of the isolates.The genome map of Y23 revealed a chromosome alongside two plasmids.The chromosome containedonly one resistance gene but several virulence factors,including the type III secretion system(T3SS),which is crucial for bacterial invasion.The plasmid pY23-1 contained eight types of 19 ARGs.Comparative analysis indicated that pY23-1 ex-hibited high homology with pZ1323SSL0055 and pSAL-045,all of which contained multiple ARGs,thus suggesting critical roles of these genes in the evolution of bacterial resistance.In conclusion,ST314 S.Kentucky demonstrated a complex mechanism of resis-tance coupled with significant pathogenic potential.The ARGs and MGEs in the plasmid contributed to the emergence and dissemina-tion of antimicrobial resistance.The multiple virulence factors present in the chromosome may be key factors driving the increasing virulence of ST314 S.Kentucky.

This study established a droplet digital PCR(ddPCR)EvaGreen assay and probe methods for Schistosoma japonicum detection,and evaluated their application in detecting early infections in the S.japonicum host oncomelania and mice.Primers and corresponding probes for both ddPCR methods were designed and synthesized,and plasmids containing target sequences were constructed.The sensitivity of the two methods was tested through detection of the corresponding plasmids,and infectious and mixed oncomelania genomic DNA.Their specificity was evaluated by the detection of genomic DNA of negative oncomelania,Schistosoma mansoni,Clonorchis sinensis,Spirometra mansoni,and S.japonicum(as a positive control).The ddPCR probe method was evaluated by detection of early infection of oncomelania exposed tomiracidium with various ratios and incubation times,and the early migration and distribution of cercaria or schistosomula in mouse hosts infected with 200 cercaria via abdominal skin contact.According to standard curves constructed through the detection of plasmid serial dilutions,the regression equation for the EvaGreen assay was y=-0.839 9x+7.050 9,with a correlation coefficient R2=0.988 1,and the regression equation for the probe method was y=-1.047 5x+7.255 1,with a correlation coefficient R2=0.999 8.The lowest limit of plasmid detection with the probe method was between 38.94 cp/μL and 194.74 cp/μL.Both methods successfully detected positive reactions in the genomic DNA samples of infectious oncomelania at concentrations above 0.002 ng/μL and in the genomic DNA of each group of oncomelania mixtures.No significant differences between probe methods were observed in the detection values in the control group and the genomic DNA of negative oncomelania,S.mansoni,C.sinensis,and S.mansoni.However,the detection value of genomic DNA of negative oncomelania(291 ng/μL)with the EvaGreen assay was(20.3±4.39)cp/μL,a value significantly higher than the(1.5±0.1)cp/μL observed in the control group.For detection of early infection in oncomelania,the probe method detected Schistosoma japonicum DNA after 30 s incubation at room temperature with a≥5∶1 ratio of miracidium to oncomelania;the detection value peaked after a short time(5 min),and the peak value showed a fold increase similar to the increase in the miracidium to oncomelania ratio.Detection of early stage infection in mice with the probe method revealed that the schistosomula entered the lungs on day 2 and the liver on day 4,and continually migrated within the organs with abundant blood supply(spleen,kidney,and brain)in the first 9 days;moreover,a tendency toward ectopic parasitism was observed in the heart and pancreas on day 9,and a constantly negative control level was observed in the testes.The ddPCR probe method was more accurate and specific than the EvaGreen assay in the detection of plasmids,and infectious and mixed oncomelania,and the latter showed non-specific reactions in negative oncomelania detection.In a practical application,the probe method was demonstrated to be sensitive,to effectively reflect the early infection of oncomelania,and to reveal schistosomula migration and distribution in multiple organs of infected mice.

Migratory birds are found worldwide.These birds are natural carriers of pathogens,because of their long-distance mi-grations across different climatic and geographic regions.The pathogens carried by migratory birds can enter ecosystems along migra-tory routes through direct and indirect contact between animal hosts,thereby potentially threatening the health of local poultry and even humans.Herein,we systematically analyzed evidence of pathogen spillover between migratory birds and poultry,and summa-rized the three modes of long-distance pathogen transmission by migratory birds(internal carriage,surface carriage,and environmen-tal contamination),as well as the two pathways of pathogen spillover between migratory birds and poultry(direct contact and indirect contact).Furthermore,this study proposes a multi-tiered mitigation strategy,grounded in the One Health framework,for targeting animal-environment-human interfaces to decrease the pathogen transmission risks associated with migratory birds.Key interventions include establishing an early-warning surveillance system for migratory flyways,enhancing biosecurity protocols in poultry production systems,and developing cross-regional risk assessment models for pathogen spread.Our findings provide critical theoretical founda-tions and empirical evidence for preventing zoonotic disease emergence and safeguarding sustainable poultry production.This inte-grated approach advances the coordinated development of biosafety measures and global health security.

Chagas disease(American trypanosomiasis)is a zoonosis caused by Trypanosoma cruzi,which severely affects public health.Recently,with changes in economic globalization and increased population mobility,this disease has gradually spread from the original Latin American epidemic areas to non-epidemic areas,such as Europe,thus showing a trend of globalization.The main trans-mission routes have changed from transmission via the Triatomine vector to blood transfusion transmission,mother-to-child transmis-sion,oral transmission,and other routes.Consequently,Chagas disease is spreading globally,and more people are increasingly vul-nerable to infection.This article retrospectively reviews research on the transmission routes of Chagas disease,analyzes the changing trends in transmission routes,and provides a scientific basis for the formulation and optimization of Chagas disease prevention and con-trol strategies from a One Health perspective.

This study analyzed the genetic evolutionary characteristics of sandflies and their effects on the spread of kala-azar in various environments in endemic provinces in China,to provide a scientific basis for kala-azar disease prevention and control.Sand-flies were collected in kala-azar endemic areas such as southern Xinjiang,the large hilly areas of southern Gansu,the northern Sich-uan and Taihang Mountains,and surrounding small hills.The cytochrome c oxidase subunit I and cytochrome b gene fragments of mito-chondrial DNA were amplified to identify sandfly species.The COI and Cytb gene sequences of sandflies from southern Xinjiang and Si-chuan recorded in NCBI were also collected.The intraspecific and interspecific genetic differences of sandflies were calculated in MEGA11.0,and a phylogenetic tree was constructed through the neighbor-joining method,for analysis of the genetic and evolutionary characteristics of sandfly populations and their effects on disease transmission.A total of 155 sandflies were collected from nine sam-pling sites in seven provinces of China;the species included Phlebotomus chinensis,Phlebotomus wui,and Sergentomyia squamirostris.Five sandfly species belonging to two genera were collected:P.chinensis,P.wui,and Phlebotomus alexandri in the genus Phleboto-mus,and S.squamirostris in the genus Sergentomyia.Genetic evolution analysis based on COI and Cytb gene sequences indicated intra-specific genetic distances of 0-0.062 and 0-0.056,respectively,and interspecific genetic distances of 0.126-0.176 and 0.110-0.171,respectively.The phylogenetic tree indicated that P.wui,P.alexandri,Phlebotomus longiductus,and S.squamirostris clus-tered into one branch.The sequences of P.chinensis in the large and small hilly areas clustered into two geographical clades.In the small hilly areas,the sequences of P.chinensis aggregates showed small genetic differences,the pathogen infection was consistent,and the cases showed an epidemic spread trend.Large genetic differences at the molecular level were observed among sandflies in dif-ferent ecological regions,thus indicating key effects on leishmaniasis transmission.On the basis of these findings,prevention and con-trol strategies should be adapted to local conditions,and precise and effective prevention and control measures should be formulated according to the genetic evolution characteristics of sandflies in different regions,to better control the transmission of Kala-azar.

This study explored the effects and underlying mechanism of Raf kinase inhibitory protein(RKIP)on apoptosis in mast cells sensitized by Echinococcus granulosus cyst fluid.Bone marrow-derived mast cells(BMMCs)were isolated and cultured from RKIP knockout(KO)and wild-type(WT)C57BL/6 mice.Cells were divided into control and sensitized groups.The sensitized group was incubated for 24 h in RPMI1640 medium containing 10%serum from mice infected with E.granulosus,then activated for 3 h or 6 h with E.granulosus cyst fluid.The control group was incubated for 24 h in RPMI1640 medium,and then received an equal vol-ume of PBS.Cells and supernatants were collected for analysis.Flow cytometry was used to detect the expression of CD117 and FcεRⅠα on BMMCs.The levels of β-hexosaminidase,IL-4,and TNF-α in the supernatant were quantified with ELISA.Western blot analy-sis was used to assess expression changes in RKIP,apoptosis-related proteins,and pathway proteins in BMMC before and after sensi-tization.Flow cytometry analysis revealed that after 4 weeks of induction,the CD117 and FcεRⅠα double-positivity rates on both WT and KO BMMC exceeded 90%.ELISA indicated that the E.granulosus cyst fluid resulted in significantly greater β-hexosaminidase re-lease(F=16.88,P<0.05),and levels of IL-4(F=16.51,P<0.05)and TNF-α(F=9.78,P<0.05)in the KO sensitized group than the WT sensitized group.With respect to the WT control group,the WT sensitized group showed significantly down-regulated pro-tein expression levels of RKIP(F=8.20,P<0.05)and Bcl-2(F=101.40,P<0.01)after 3 h,but significantly up-regulated levels of p-PI3K(F=8.04,P<0.05),p-Akt(F=32.52,P<0.01),p-P65(F=13.29,P<0.05),and cleaved-caspase-3(F=46.34,P<0.01).With respect to the WT sensitized group,the KO sensitized group showed significantly up-regulated protein expression of p-PI3K(F=8.45,P<0.05),p-Akt(F=8.58,P<0.05),p-P65(F=11.02,P<0.05),and Bcl-2(F=84.50,P<0.001)after 3 h,but significantly down-regulated expression of cleaved-caspase-3(F=15.66,P<0.05).In conclusion,RKIP may inhibit the PI3K/Akt/NF-κB pathway,thereby inducing apoptosis in mast cells sensitized by E.granulosus cyst fluid.This process may help ease aller-gic reactions caused by mast cells in echinococcosis,thus offering a promising new approach for preventing and treating such reactions.

The infection incidence rate of Candida albicans,an opportunistic pathogenic fungus,has increased each year.Currently,the increased number of patients with immunodeficiency,the limited number of antifungal drugs,and drug resistance are the main reasons for the high incidence and high mortality of C.albicans related diseases.Therefore alternative therapies for combating C.albicans infections are urgently needed.Many recent studies have suggested that probiotics might inhibit C.albicans infection both directly,through inhibiting adhesion,growth,and biofilm formation,and indirectly,through regulating the host immune response,without leading to drug resistance.Because of the multiple pathways involved in these effects,the mechanism of probiotics in combating C.albicans infection has not been fully elucidated,and systematic evaluations of this mechanism are lacking.This article provides an in-depth analysis of the mechanism of probiotics in combating C.albicans infection described in recent years,to contribute to the development of new methods to resist C.albicans infection and,more importantly,the clinical development of new therapies for the treatment of drug-resistant fungal infections.

An analysis of 24 144 norovirus sequences from Asia and Russia deposited in GenBank between 1995 and 2023 was conducted,to understand the temporal and spatial variations in norovirus genotypes in these regions.Norovirus sequences from Asia and Russia were downloaded in FASTA format from GenBank for the years 1995-2023,and analyzed in Excel,R language,and GraphPad Prism for data visualization.The number of norovirus sequences submitted to GenBank increased annually from 2004 and peaked in 2015.Notably,China and Japan contributed 62.3％of all submitted norovirus sequences.These sequences encompassed 31 capsid genotypes(C-type),with GⅠ accounting for 9％and GⅡ accounting for 90％.Additionally,49 polymerase types(P-type)were identified,along with 68 combinations of CP types;among the analyzed recombinant sequences(4 460 entries in total),approxi-mately 41％belonged to three predominant recombinant strains:GⅡ.2[P16],GⅡ.4[P31],and GⅡ.4[P16].This analysis provides valuable insights into the distribution characteristics of norovirus genotypes across Asia and Russia over time,thereby supporting vac-cine design and evaluation efforts.

To understand the background of Escherichia coli(E.coli)carried by artificially bred sika deer and the biological characteristics of the isolated strains,such as drug resistance and pathogenicity,in April 2024,we collected 184 fresh deer fecal samples from four deer farms in Luxiang Township,Shuangyang District,Changchun City,Jilin Province,for isolation and cultivation of E.coli.The isolates were tested for drug resistance and biochemical identification with a BD PhoenixTM-100 Automated Microbiology System.The virulence genes were detected with PCR,and the strains were molecularly typed with ERIC-PCR.A total of 165 E.coli strains were isolated from 184 samples of deer feces,with an isolation rate of 89.67%.Twenty strains had a drug resistance phenotype,and the drug resistance rate was 12.12%;these strains included 15 strains of multi-drug resistant bacteria and 11 strains of ESBL-producing bacteria.Virulence gene detection indicated that the sika deer isolates carried multiple diarrhea-associated virulence genes,such as EAST-1(12.12%),eae(1.21%),stx1(7.88%),stx2(7.27%),and STa(1.82%).ERIC-PCR demonstrated that the isolates showed high polymorphism.The ESBL-producing E.coli carried by sika deer are likely to spread drug resistance in the community and livestock population.Some isolates carried multiple diarrhea-associated virulence genes,thus posing a human transmission risk.Therefore,monitoring of drug resistance and virulence genes must be strengthened,and antibiotics must be used reasonably during the breeding process to avoid excessive use and misuse.

This study investigated the infection status,drug resistance,and molecular characteristics of Shiga toxin-producing Escherichia coli(STEC)in domestic goats in Chengkou county,Chongqing.In August 2023,283 fecal samples were collected from households in Chengkou county.After enrichment with EC broth and inoculation onto selective media,samples that tested positive for stx1/stx2 were selected for further isolation.The positive strains were investigated with antimicrobial susceptibility testing and whole genome sequencing.According to the whole genomic sequences,the stx subtypes,serotypes,multi-locus sequence types,virulence genes,drug resistance genes,and phylogenetic relationships of the STEC strains were analyzed.Forty-six strains of STEC were isolated from 283 goat fecal samples,thus resulting in a detection rate of 16.25%.The 46 STEC strains were categorized into 12 O∶H serotypes,among which O76∶H19 and O8∶H7 predominated,each represented by 9 strains.Five STEC strains were identified as serotype O157∶H7.The 46 STEC strains were categorized into 11 sequence types(STs),among which ST675 and ST196 predominated,each represented by nine strains,accounting for a 19.57%proportion.The strains were categorized into 7 stx subtypes,among which stx1c(26/46,56.52%),followed by stx2k(9/46,19.57%)predominated.All nine Stx2k-STEC strains were identified as serotype O8∶H7 and sequence type ST196.In antimicrobial susceptibility testing,2 STEC strains were resistant to ampicillin,one strain was resistant to ampicillin/sulbactam,one strain was resistant to cefazolin,and one strain was resistant to cefoxitin.Nine Stx2k-STEC strains were found to carry the beta-lactam resistance gene blaEC-18.Antimicrobial sensitivity tests revealed that the nine Stx2k-STEC strains were sensitive to all 15 tested antibiotics.Moreover,phylogenetic analysis indicated that the 9 Stx2k-STEC strains were remarkably similar but showed high genetic diversity with respect to that of the Stx2k-STEC strains isolated from other regions in China.Goatsare an important animal reservoir for STEC in theChengkou district of Chongqing,and novel sequence type Stx2k-STEC strains distinct from those found in other regions of China were identified in this region.