Human Infection Research Articles

A fatal case of cupriavidus pauculus causing septicemia after duodenal perforation: Case report from university teaching hospital

, a gram-negative bacterium is found ubiquitously in soil and water. It is very rare organism to cause human infection. Here we report a fatal case of septicaemia due to in a young female with duodenal perforation. Blood culture showed isolation of identified by MALDI-TOF-MS. The patient was treated with meropenem and piperacillin and tazobactam, but she died nine days after surgery. To our knowledge, this is the rare case report of causing septicemia after duodenal perforation.

Molecular characterization of human astrovirus infection in children under 5 years of age with acute gastroenteritis in Tehran, Iran, 2021-2022: co-infection with rotavirus.

Human astroviruses (HAstVs) are considered important causative pathogens of acute gastroenteritis (AGE) in children under 5 years of age worldwide, along with group A rotavirus (RVA), norovirus (NoV), and enteric adenovirus (EAdV). The present study was aimed to both detect HAstV and its co-infections and investigate genetic analysis of circulating HAstV and co-infected virus in hospitalized children under 5 years of age with AGE in Iran. Accordingly, a sum of 200 stool specimens were screened by PCR for HAstV during 2021-2022. The HAstV was found in 0.5% of 200 specimens (n = 1) while was co-infected with RVA. The genetic and phylogenetic analysis indicated HAstV1 genotype, which clustered with viruses from lineage 1b, which has not been previously reported in Iran. The detected RVA strain belonged to G1 lineage II/P[8]-lineage III, which has been reported previously in Iran as the most common strain. The further genetic analysis of RVA VP6 and NSP4 demonstrated an atypical genotype pattern G1P[8]-I1-E2, as a mono-reassortant of a Wa-like genogroup, which appeared to be reassorted with the NSP4 gene of E2 genotype of the G2P[4] DS-1 genogroup. Although the clinical outcomes of the AGE-causing viruses co-infection is not yet entirely clear, it seems that future studies will be helpful to merge clinical and epidemiological data of co-infecting viruses for a more accurate medical and clinical relevance in symptomatic children.

Identification of Trichophyton benhamiae by MALDI-TOF Mass Spectrometry. First report in Peru

is an emerging zoophilic dermatophyte that mainly infects skin and scalp and has been reported in Asia, America and Europe. It has two phenotypic variants: one with white colonies and the other with yellow colonies. Morphological identification of is not sufficient and can be confused with or . Genomic or proteomic analysis is required to establish a definitive identification. We present three dermatophyte strains obtained from the skin, nails and scalp of human infections in which macroscopic and microscopic examinations were not sufficient to identify the species. The final identification of was performed using MALDI-TOF mass spectrometry. This is the first report of in Peru.

Seroprevalence of Rickettsia Spp. and Orientia tsutsugamushi in Indigenous Populations from the Sierra Nevada de Santa Marta, Colombia.

Background: Rickettsia spp. are vector-borne zoonotic pathogens that cause febrile illness in humans. Rickettsioses is not included in the Colombian national surveillance system and is subsequently expected to be underreported. This cross-sectional study aimed to determine the seroprevalence of Rickettsia spp. and the closely related Orientia tsutsugamushi in two indigenous populations residing in the Sierra Nevada de Santa Marta, Colombia. Materials and Methods: Serum samples (n = 539) were collected from the Wiwa and Koguis people between 2021 and 2022. Serum samples were screened for spotted fever group (SFG) and typhus group (TG) Rickettsia spp. using the Fuller laboratories Rickettsia IgG IFA kit and for O. tsutsugamushi with the Scrub Typhus Detect™ IgG ELISA. Results: We observed an overall seroprevalence of 26.2% (95% confidence interval [CI] 22.5-30.1] for Rickettsia spp. of the SFG, 5.4% (95% CI 3.6-7.6) for Rickettsia spp. of the TG and 4.3% (95% CI 2.7-6.3) for O. tsutsugamushi. Common risk factors for zoonotic disease infections were assessed for 147 of the Wiwa participants. Increased odds of seropositivity for SFG Rickettsia spp. were observed for Wiwa participants who cared for livestock, including assisting with the birth of cattle (odds ratio [OR] = 8.85; 95% CI 1.54-50.90; p = 0.015) and goats (OR = 7.60; 95% CI 1.70-33.90; p = 0.008). Conclusions: These results highlight a notable exposure to Rickettsia spp., especially the SFG, in rural Colombia. Together with recent reports of high mortality for Rocky Mountain Spotted Fever in nearby regions of South America, more detailed investigations focusing on improving knowledge and awareness as well as "One Health" and "causes-of-fever" studies are needed. The characterization of Rickettsia spp. infections in humans, livestock, and tick vectors with their potential transmission routes could make a high impact on these easily treatable diseases.

Clinical spectrum and epidemiology of Human Parechovirus infections in infants - a retrospective study in the Western part of Sweden

Clinical spectrum and epidemiology of Human Parechovirus infections in infants - a retrospective study in the Western part of Sweden

Long-term occurrence of multiple antimicrobial drug resistant Klebsiella pneumoniae isolates harboring virulent potential in a tertiary hospital from Brazil.

Klebsiella pneumoniae strains are globally associated with a plethora of opportunistic and severe human infections and are known to spread genes conferring antimicrobial resistance. Some strains harbor virulence determinants that enable them to cause serious disease in any patient, both in the hospital and in the community. The aim of this study was to determine the frequency of antimicrobial resistance and virulence traits (by gene detection and string test) among 83K. pneumoniae isolates obtained from patient cultures of a scholar tertiary hospital in the Midwestern Brazil (Brasília, DF). Antimicrobial susceptibility analysis showed that 94% (78/83) of the isolates presented one of the following resistance profiles: resistant (R, 39), multidrug-resistant (MDR, 29), or extensively drug-resistant (XDR, 10). Several MDR and XDR strains harbored multiple virulence genes and displayed hypermucoviscous phenotype. These characteristics were observed among isolates obtained throughout all the sample collection period (2013 - 2017). The K2 serotype gene, a molecular marker of hypervirulence, was detected in three isolates, one of which classified as XDR. Sequence typing revealed the occurrence of isolates belonged to high-risk (ST13) and multiple resistance-spreading clones (ST105). Thus, our findings showed the occurrence of virulent potential isolates that also presented MDR/XDR phenotypes from 2013 to 2015. This study also indicates the probable convergence of virulence and resistance since at least 2013 in Brazil.

Occurrence of Pantoea agglomerans bloodstream infection in neonatal intensive care unit at tertiary hospital in Tanzania: antibiotic susceptibility profile and clinical outcome

BackgroundPantoea agglomerans (P. agglomerans) is an environmental gram-negative bacterium that rarely infects humans. P. agglomerans infections have never been reported in Tanzania. We investigated the occurrence of P. agglomerans bloodstream infections among neonates in the Intensive Care Unit (NICU) and their subsequent clinical outcome that occurred in 2019.MethodologyBlood samples were collected from neonates with sepsis. A total of 19 P. agglomerans were isolated from 17 infected neonates; two of the neonates had P. agglomerans isolated twice. A total of 14 patient files were retrieved from medical records.ResultsThe mean age of the infected neonates were 3.75 ± 7.95 days. Isolated P. agglomerans showed high sensitivity to the antibiotics particularly chloramphenicol (94.7%), piperacillin-tazobactam (94.7%) and meropenem (94.7%). The mortality rate was 71.4% with 35.7% of infected neonates dying before Antibiotic Susceptibility Test results for appropriate management. The Infection Prevention and Control (IPC) team shut the NICU for thorough decontamination which helped to stop the P. agglomerans occurrence.ConclusionsP. agglomerans occurrence at the NICU was an uncommon aetiology pathogen for neonatal sepsis associated with high rates of mortality despite high sensitivity to multiple antibiotics. This calls for the strengthening of infection control measures and introduction of surveillance for environmental pathogens capable of causing human infections.

Infectious etiologies of persistent and chronic diarrhea in Asian developing countries: A systematic review and meta-analysis.

Infectious causes of diarrhea contribute significantly to morbidity in Asia. We conducted a systematic review and meta-analysis of the prevalence of infectious etiologies of persistent and chronic diarrhea in Asian adults. Searches were performed on PubMed and Scopus for studies from January 1, 1970, to May 30, 2023. Sixteen studies were identified and included. The meta-analysis was conducted with the random-effects method, estimating the pooled prevalence of groups of infectious pathogens as causes of persistent and chronic diarrhea among Asian adults. The findings were highly heterogeneous and indicative of publication bias. The majority of studies were conducted on persons living with human immunodeficiency virus infection (PLHIV). The studies were predominantly from low-income and middle-income Asian countries. The most common cause was parasitic, with a pooled prevalence of 0.52 (95% confidence interval 0.28-0.65, I2=99%, Cochran's Q=1027.44, P<0.01), followed by bacterial, fungal, and viral causes, which were substantially rarer. Negative microbiological testing was also common, with a pooled prevalence for a negative test being 0.37 (95% confidence interval 0.17-0.52, I2=99%, Cochran's Q=1027.44, P<0.01). Subgroup analyses of studies conducted among PLHIV, from year 2000 and among those conducted in Southeast Asia showed a similar prevalence of parasitic causes of diarrhea. In conclusion, inAsian adults with persistent and chronic diarrhea, parasitic causes were most prevalent. However, the estimate of true prevalence is limited by significant heterogeneity among the available studies. More study in this field is required, especially examining PLHIV in the post-antiretroviral therapy era and from high-income countries.

Human papillomavirus infection and the risk of cancer at specific sites other than anogenital tract and oropharyngeal region: an umbrella review

Despite numerous studies having evaluated the associations between human papillomavirus (HPV) infection and risk of specific cancers other than anogenital tract and oropharyngeal, the findings are inconsistent and the quality of evidence has not been systematically quantified. We aimed to summarise the existing evidence as well as to evaluate the strength and credibility of these associations. We conducted an umbrella review of systematic reviews and meta-analyses of observational studies. PubMed, EMBASE, and Web of Science were searched from inception to March 2024. Studies with systematic reviews and meta-analyses that examined associations between HPV or HPV-associated genotypes infection and specific cancers were eligible for this review. The quality of the methodology was evaluated using A Measurement Tool to Assess systematic Reviews (AMSTAR). The credibility of the evidence was assessed using GRADE. The protocol was preregistered with PROSPERO (CRD42023439070). The umbrella review identified 31 eligible studies reporting 87 associations with meta-analytic estimates, including 1191 individual studies with 336,195 participants. Of those, 29 (93.5%) studies were rated as over moderate quality by AMSTAR. Only one association indicating HPV-18 infection associated with an increased risk of breast cancer (odds ratio [OR]=3.48, 95% confidence interval [CI]=2.24-5.41) was graded as convincing evidence. There were five unique outcomes identified as highly suggestive evidence, including HPV infection increased the risk of oral squamous cell carcinoma (OR=7.03, 95% CI=3.87-12.76), oesophageal cancer (OR=3.32, 95% CI=2.54-4.34), oesophageal squamous cell carcinoma (OR=2.69, 95% CI=2.05-3.54), lung cancer (OR=3.60, 95% CI=2.59-5.01), and breast cancer (OR=6.26, 95% CI=4.35-9.00). According to GRADE, one association was classified as high, indicating that compared with the controls in normal tissues, HPV infection was associated with an increased risk of breast cancer. The umbrella review synthesised up-to-date observational evidence on HPV infection with the risk of breast cancer, oral squamous cell carcinoma, oesophageal cancer, oesophageal squamous cell carcinoma, and lung cancer. Further larger prospective cohort studies are needed to verify the associations, providing public health recommendations for prevention of disease. National Key Research and Development Program of China, Natural Science Foundation of China, Outstanding Scientific Fund of Shengjing Hospital of China Medical University, and 345 Talent Project of Shengjing Hospital of China Medical University.

Spectrum of Treg and Self-Reactive T cells: Single Cell Perspectives from Old Friend HTLV-1

Summary Despite extensive regulatory T cell (Treg) research, fundamental questions on in vivo dynamics remain to be answered. The current study aims to dissect several interwoven concepts in Treg biology, highlighting the ‘self-reactivity’ of Treg and their counterparts, namely naturally-arising memory-phenotype T-cells, as a key mechanism to be exploited by a human retroviral infection. We propose the novel key concept, Periodic TCR-signalled T-cells, capturing self-reactivity in a quantifiable manner using the Nr4a3-Timer-of-cell-kinetics-and-activity (Tocky) technology. Periodic and brief TCR signals in self-reactive T-cells contrast with acute TCR signals during inflammation. Thus, we propose a new two-axis model for T-cell activation by the two types of TCR signals or antigen recognition, elucidating how Foxp3 expression and acute TCR signals actively regulate Periodic TCR-signalled T-cells. Next, we highlight an underappreciated branch of immunological research on Human T-cell Leukemia Virus-1 (HTLV-1) that precedes Treg studies, illuminating the missing link between the viral infection, CD25, and Foxp3. Based on evidence by single cell analysis, we show how the viral infection exploits the regulatory mechanisms for T-cell activation and suggests a potential role of Periodic TCR signalling in infection and malignant transformation. In conclusion, the new perspectives and models in this study provide a working framework for investigating Treg within the self-reactive T-cell spectrum, expected to advance understanding of HTLV-1 infection, cancer, and immunotherapy strategies for these conditions.

Protective role of RIPK1 scaffolding against HDV-induced hepatocyte cell death and the significance of cytokines in mice.

Hepatitis delta virus (HDV) infection represents the most severe form of human viral hepatitis; however, the mechanisms underlying its pathology remain incompletely understood. We recently developed an HDV mouse model by injecting adeno-associated viral vectors (AAV) containing replication-competent HBV and HDV genomes. This model replicates many features of human infection, including liver injury. Notably, the extent of liver damage can be diminished with anti-TNF-α treatment. Here, we found that TNF-α is mainly produced by macrophages. Downstream of the TNF-α receptor (TNFR), the receptor-interacting serine/threonine-protein kinase 1 (RIPK1) serves as a cell fate regulator, playing roles in both cell survival and death pathways. In this study, we explored the function of RIPK1 and other host factors in HDV-induced cell death. We determined that the scaffolding function of RIPK1, and not its kinase activity, offers partial protection against HDV-induced apoptosis. A reduction in RIPK1 expression in hepatocytes through CRISPR-Cas9-mediated gene editing significantly intensifies HDV-induced damage. Contrary to our expectations, the protective effect of RIPK1 was not linked to TNF-α or macrophage activation, as their absence did not alter the extent of damage. Intriguingly, in the absence of RIPK1, macrophages confer a protective role. However, in animals unresponsive to type-I IFNs, RIPK1 downregulation did not exacerbate the damage, suggesting RIPK1's role in shielding hepatocytes from type-I IFN-induced cell death. Interestingly, while the damage extent is similar between IFNAR KO and WT mice in terms of transaminase elevation, their cell death mechanisms differ. In conclusion, our findings reveal that HDV-induced type-I IFN production is central to inducing hepatocyte death, and RIPK1's scaffolding function offers protective benefits. Thus, type-I IFN together with TNF-α, contribute to HDV-induced liver damage. These insights may guide the development of novel therapeutic strategies to mitigate HDV-induced liver damage and halt disease progression.

Overexpression of PDR16 Confers Amphotericin B Resistance in a PMP3-Dependent Manner in Yeast Saccharomyces cerevisiae.

Invasive fungal infections in humans with compromised immune systems are the primary cause of morbidity and mortality, which is becoming more widely acknowledged. Amphotericin B (AmB) is one of the antifungal drugs used to treat such infections. AmB binds with plasma membrane ergosterol, inducing cellular ions to leak and causing cell death. Reduction in ergosterol content and modification of cell walls have been described as AmB resistance mechanisms. In addition, when the sphingolipid level is decreased, the cell becomes more susceptible to AmB. Previously, PDR16, a gene that encodes phosphatidylinositol transfer protein in Saccharomyces cerevisiae, was shown to enhance AmB resistance upon overexpression. However, the mechanism of PDR16-mediated AmB resistance is not clear. Here, in this study, it was discovered that a plasma membrane proteolipid 3 protein encoded by PMP3 is essential for PDR16-mediated AmB resistance. PDR16-mediated AmB resistance does not depend on ergosterol, but a functional sphingolipid biosynthetic pathway is required. Additionally, PMP3-mediated alteration in membrane integrity abolishes PDR16 mediated AmB resistance, confirming the importance of PMP3 in the PDR16 mediated AmB resistance.

Comparison of Direct and Indirect Detection of Toxoplasma gondii in Ovine Using Real-Time PCR, Serological and Histological Techniques

Toxoplasma gondii is a zoonotic pathogen and the ingestion of tissue cysts by consumption of lamb or mutton has been identified as a possible cause of infection in humans. Many serological surveys in sheep have been performed, showing relevant serological rates; however, while the detection of antibodies indicates an exposure to T. gondii, this does not necessarily imply the presence of tissue cysts in edible tissue. The current study aims to provide further understanding on the occurrence of T. gondii in sheep muscles and the strength of correlation between serological positivity and presence of the parasite in sheep. From 349 sheep, samples (i.e., blood, heart and diaphragm) were collected and subjected to ELISA tests, real-time PCR and histological tests. Despite the high seroprevalence, T. gondii DNA was detected in the heart and/or the diaphragm from 13 out of the 349 tested sheep (3.7%); all were adults (13/191). Furthermore, the histological tests did not reveal the presence of T. gondii tissue cysts in any of the examined portions of interventricular septum. It should be considered that the likelihood of detecting genetic material of the parasite is probably influenced by the uneven distribution of the tissue cysts in the carcass as well as the methodology applied. The findings of this study support the importance of describing the uncertainty associated with the data used for risk assessment to reduce inaccurate estimation or risk overestimation.

Left knee septic monoarthritis in a pediatric patient due to shewanella putrefaciens: case report and literature review

BackgroundShewanella putrefaciens is a gram-negative, nonfermenting, oxidase-positive, hydrogen sulfide-producing bacillus and a halophilic bacterium, known for causing unusual infections in humans and often regarded as an opportunistic pathogen. Its diverse symptoms have a significant impact on human health, with 260 documented disorders reported in the literature over the last 40 years, highlighting its potential danger.Case presentationWe present the case of a previously healthy 15-year-old male patient who sustained a self-inflicted sharp-object injury while working in the field, resulting in secondary septic monoarthritis due to Shewanella putrefaciens.ConclusionsThis case highlights the bacteriological and clinical characteristics, as well as the antibiogram, of Shewanella spp. Given the recent increase in notifications of Shewanella infections, predominantly by S. algae and S. putrefaciens, it is essential to consider these pathogens in patients with a history of contact with bodies of water. Special attention must be paid to their resistance patterns in patient management to prevent the development of intrinsic antimicrobial resistance.

Characterisation of a Japanese Encephalitis virus genotype 4 isolate from the 2022 Australian outbreak

Human infections with the Japanese encephalitis virus (JEV) are a leading cause of viral encephalitis. An unprecedented outbreak of JEV genotype 4 was recently reported in Australia, with an isolate (JEVNSW/22) obtained from a stillborn piglet brain. Herein we conduct a thorough characterization of JEVNSW/22 in three different mouse strains and in human cortical brain organoids (hBOs), and determined the ability of JEVNSW/22 to be neutralized by sera from humans vaccinated with IMOJEV. JEVNSW/22 was less virulent than JEVFU (genotype 2) and JEVNakayama (genotype 3) in C57BL/6J mice and in interferon regulatory factor 7 deficient (Irf7−/−) mice, with infection of wild-type and knockout murine embryonic fibroblasts indicating JEVNSW/22 is more sensitive to type I interferon responses. Irf7−/− mice provide a new model for JEVNSW/22, showing higher viremia levels compared to C57BL/6J mice, and allowing for lethal neuroinvasive infection. All JEV strains were universally lethal in Ifnar−/− mice by day 3, with histological signs of brain hemorrhage, but no other lesions. There were no indications of brain infection in Ifnar−/− mice, with viral protein detected in blood vessels, but not neurons. All JEV isolates showed robust cytopathic infection of human cortical brain organoids, albeit lower for JEVNSW/22. IMOJEV vaccination in humans induced antibodies capable of neutralizing JEVNSW/22, although, for all JEV strains, cross-neutralization titers declined with increasing divergence from IMOJEV in the envelope amino acid sequences. Overall, our study establishes JEVNSW/22 mouse and hBO models of infection, allowing for possible lethal neuroinvasive infection in mice that was rarer than for other JEV genotypes. JEV vaccination regimens may afford protection against this newly emerged JEV genotype 4 strain, although neutralizing antibody responses are sub-optimal.

Analysis and Validation of the Network Pharmacology of the Mechanism of Glycyrrhetinic Acid for the Treatment of High-Altitude Pulmonary Hypertension

Glycyrrhetinic acid (GA) is a pentacyclic triterpene component in Glycyrrhize glabra L, it has demonstrated an inhibitive effect on high-altitude pulmonary hypertension (HAPH), but the molecular action is still not known. We aimed to explore the mechanism of GA for the treatment of HAPH based on network pharmacology and molecular docking method. Cell experiment validation was also conducted. The targets for GA were screened using the Swiss Target Prediction and Batman databases. The HAPH-related targets were obtained using the GeneCards and OMIM databases. The common targets for diseases and drugs were obtained using a Venn diagram. The core targets were screened using the String database. Then, a component-target-disease diagram and protein–protein interaction (PPI) network mutual assistance diagram were developed using Cytoscape3.9.1 software. GO functional and KEGG pathway enrichment analyses were conducted using the Metascape database. Finally, molecular docking of the target and its corresponding active components were performed using Autodock software. A total of 68 common targets for glycyrrhetinic acid high-altitude pulmonary hypertension were screened out. The core targets include PTGS1, MMP1, SERPINA6, and nitric oxide synthase (NOS2), involving PPAR signal pathway, human cytomegalovirus infection, IL-17 signal pathway, proteoglycans in cancer, and other pathways. The molecular docking affinity was −8.4 kcal·mol−1 in average, indicating that GA has a good binding stability with key target proteins. In the PDGF-BB-induced PASMC proliferation model, PASMC proliferation and the p-p38, p38, p-ERK1/2, and ERK1/2 protein expression were inhibited. The pharmacological mechanism of GA for the treatment of HAPH was characterized by multi-target and multi pathway. GA may serve as a promising therapeutic candidate for HAPH but still needs further in vivo/in vitro experiment.

Transcriptionally Active Human Papillomavirus Infection in a Minority of Esophageal Squamous Cell Carcinomas in North America.

The role of Human papillomavirus (HPV) infection in esophageal squamous cell carcinoma (ESCC) is a topic of ongoing debate. This study used two screening approaches to look for evidence of HPV infection in esophageal squamous cell carcinoma. We initially checked for HPV infection in a randomly selected group of 53 ESCC cases. We did not detect any tumors positive for high-risk HPV. However, during clinical practice, we identified an HPV-positive ESCC in the distal esophagus, which tested positive for HPV16. This index case was TP53 wild-type, as determined by next-generation DNA sequencing (NGS). Since TP53 mutations are rare in other HPV-driven cancers, we improved our screening method by limiting our screen to a subset of ESCC cases without TP53 mutations. A second screen of 95 ESCCs (from 93 patients) sequenced by NGS revealed an additional 7 ESCCs with TP53 wild-type status (7.3% of the total). Of the 7 cases, 2 cases were found to be high-risk HPV positive. Both patients also tested positive for circulating cell-free HPV DNA and had a complete response to neoadjuvant chemoradiation. The index patient had microscopic residual tumor following neoadjuvant therapy. The patient underwent adjuvant immunotherapy and remained disease free after 22 months of surveillance. This study affirms the transcriptionally active status of high-risk HPV in a minority of ESCC patients in North America.

Brucella spp. in Wildlife of the Lombardy Region, Northern Italy.

Surveillance data collected in the period 2017-20 for Brucella spp. in wildlife of the Lombardy Region in northern Italy were used to describe the exposure of the wildlife species to Brucella spp. in wild boar (Sus scrofa), European brown hare (Lepus europaeus), fallow deer (Dama dama), red deer (Cervus elaphus), and roe deer (Capreolus capreolus). Among the tested species, wild boar (n=6,440) showed the highest percentage of seropositive samples (5.9%). Notably, wild boars of perifluvial area of the Po River showed higher percentages of positivity than those of the pre-Alpine district. In addition, during the hunting season in 2018, 95 organs (uterus or testes, spleen, and submandibular lymph nodes) from wild boar of the perifluvial area of the Po River were collected for bacteriological examination. Brucella suis was isolated in culture from 18.9% of tested lymph nodes. These serological and microbiological results highlight the presence of B. suis in wild boar and suggest the importance of wild boar as a reservoir for B. suis. Comparison of the spatial distribution of Brucella-seropositive wild boars with the location of backyard swine farms revealed a higher chance of contact between the two populations only in the areas where the lower percentage of seropositive samples was observed. Conversely, the high percentage of seropositive samples observed in the Po River area coupled with positive microbiological cultures suggest a greater risk of infection for the humans directly or indirectly involved in wild boar hunting activity. These results may serve as a basis to establish sound wildlife management and to adopt education campaigns aimed at reducing the risk of human infection in people involved in wild boar hunting related activities.

The distribution and antibiotic-resistant characteristics and risk factors of pathogens associated with clinical biliary tract infection in humans

IntroductionBiliary Infection in patients is a common and important phenomenon resulting in severe complications and high morbidity, while the distributions and drug resistance profiles of biliary bacteria and related risk factors are dynamic. This study explored the characteristics of and risk factors for biliary infection to promote the rational use of antibiotics in clinically.MethodsBacterial identification and drug susceptibility testing were completed using the Vitek 2 Compact analysis system. The distribution and antibiotic-resistant characteristics of 3,490 strains of biliary bacteria in patients at Nankai Hospital from 2019 to 2021 were analyzed using Whonet 5.6 and SPSS 26.0 software. We then retrospectively analyzed the clinical data and risk factors associated with 2,340 strains of Gram-negative bacilli, which were divided into multidrug-resistant bacteria (1,508 cases) and non-multidrug-resistant bacteria (832 cases) by a multivariate Cox regression model.Results and discussionA total of 3,490 pathogenic bacterial strains were isolated from bile samples, including 2,340 (67.05%) Gram-negative strains, 1,029 (29.48%) Gram-positive strains, and 109 (4.56%) fungal strains. The top five pathogenic bacteria were Escherichia coli, Klebsiella pneumoniae, Enterococcus faecium, Enterococcus faecalis, and Pseudomonas aeruginosa. The rate of Escherichia coli resistance to ciprofloxacin increased (p &amp;lt; 0.05), while the resistance to amikacin decreased (p &amp;lt; 0.05). The resistance of Klebsiella pneumoniae to cephalosporins, carbapenems, β-lactamase inhibitors, cephalases, aminoglycosides, and quinolones increased (p &amp;lt; 0.05), and the resistance of Pseudomonas aeruginosa to piperacillin, piperacillin/tazobactam, ticacillin/clavulanic acid, and amicacin declined significantly (p &amp;lt; 0.05). The resistance of Enterococcus faecium to tetracycline increased by year (p &amp;lt; 0.05), and the resistance of Enterococcus faecalis to erythromycin and high-concentration gentamicin declined (p &amp;lt; 0.05). Multivariate logistic regression analysis suggested that the administration of third- or fourth-generation cephalosporins was an independent risk factor for biliary infection. In summary, Gram-negative bacilli were the most common pathogenic bacteria isolated from biliary infection patients, especially Escherichia coli, and the rates and patterns of drug resistance were high and in constant flux; therefore, rational antimicrobial drug use should be carried out considering risk factors.

H6N2 reassortant avian influenza virus isolate in wild birds in Jiangxi Province, China.

H6 avian influenza virus is widely prevalent in wild birds and poultry and has caused human infection in 2013 in Taiwan, China. During our active influenza surveillance program in wild waterfowl at Poyang Lake, Jiangxi Province, an H6N2 AIV was isolated and named A/bean goose/JiangXi/452-4/2013(H6N2). The isolate was characterized as a typical low pathogenic avian influenza virus (LPAIV) due to the presence of the amino acid sequence PQIETR↓GLFGAI at the cleavage site of the hemagglutinin (HA) protein. The genetic evolution analysis revealed that the NA gene of the isolate originated from North America and exhibited the highest nucleotide identity (99.29%) with a virus recovered from wild bird samples in North America, specifically A/bufflehead/California/4935/2012(H11N2). Additionally, while the HA and PB1 genes belonged to the Eurasian lineage, they displayed frequent genetic interactions with the North American lineage. The remaining genes showed close genetic relationships with Eurasian viruses. The H6N2 isolate possessed a complex genome, indicating it is a multi-gene recombinant virus with genetic material from both Eurasian and North American lineages.