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Strengthening the Reporting of Observational Studies in Epidemiology Enhanced Prevalence and Incidence Criteria (STROBE EPIC): An Extension of the STROBE Statement.

Prevalence and incidence are fundamental metrics with numerous applications in epidemiology. The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guideline lacks specific items for reporting studies of disease prevalence or incidence. To address this gap, the STROBE Enhanced Prevalence and Incidence Criteria (STROBE EPIC) extension was developed in accordance with established methods for reporting guideline development. The authors generated an initial list of reporting items, conducted a modified Delphi process, and convened a face-to-face consensus meeting to confirm the need for a STROBE extension and to generate an early version of the checklist. They conducted 2 further Delphi surveys, first extending from typhoid and other invasive salmonelloses to all infectious diseases, and then to noncommunicable diseases and injuries. Finally, experts piloted the checklist on relevant manuscripts to critically assess if it was clear, concise, complete, and free of errors. An executive group curated the checklist after every survey round. The STROBE EPIC checklist comprises 47 items in the domains of title (1 item), abstract (2 items), introduction (1 item), methods (25 items), results (6 items), discussion (7 items), and other information (5 items). STROBE EPIC items address reporting of study design, adjustment factors for underreporting and underdiagnosis, denominator population estimation, case ascertainment methods, factors producing artefactual changes to observed disease prevalence or incidence, limitations of incomplete surveillance coverage, generalizability of short-duration studies, and data availability. The authors anticipate that the STROBE EPIC extension will be used by researchers, authors, modelers, burden-of-disease researchers, peer reviewers, and journal editors to optimize the presentation of epidemiologic evidence to support diverse health policy decisions.

Humans

A standardized, genome-guided MLST scheme for Avibacterium paragallinarum: enhanced epidemiological typing and validation against existing methods.

Avibacterium paragallinarum, the causative agent of infectious coryza (IC), is an important respiratory pathogen of chickens with growing prevalence in commercial and backyard flocks. Current strain-typing methods, including classical serotyping and molecular approaches, such as ERIC-PCR or single-locus HPG2 typing, lack sufficient discriminatory power to investigate the epidemiology or population structure. To address this limitation, we developed a genome-guided multilocus sequence typing (MLST) scheme as a robust and portable tool for A. paragallinarum strain differentiation. Housekeeping genes were identified from 42 whole-genome sequences (WGS); 18 candidates were evaluated; and six were selected for the final MLST scheme. We used the scheme to differentiate 75 A. paragallinarum samples and compared its performance against classical HPG2-based typing, ad hoc core genome MLST (cgMLST), and the MLST scheme published by M. Guo, Y. Jin, H. Wang, X. Zhang, and Y. Wu (Vet Sci 11:208, 2024, https://doi.org/10.3390/vetsci11050208). The new MLST showed higher discriminatory power than HPG2 and outperformed Guo's scheme with higher discriminatory power, particularly for characterizing the samples originating from North and South America. It also showed strong concordance with cgMLST clustering while being more practical for routine use. Overall, the six-locus MLST identified 31 sequence types across 75 samples, revealing epidemiologically meaningful clustering at regional and national scales and capturing temporal persistence of lineages. All allele definitions and sequence types have been deposited in PubMLST, ensuring standardized nomenclature and global accessibility. This scheme represents a reproducible, cost-effective, and globally applicable tool that enhances outbreak investigation, surveillance, and population studies of A. paragallinarum, bridging the gap between low-resolution traditional methods and resource-intensive whole-genome sequencing.IMPORTANCEInfectious coryza (IC) caused by Avibacterium paragallinarum is a major respiratory disease of poultry that causes acute infection, reducing egg production and growth and resulting in significant economic losses in poultry production worldwide. Controlling IC depends on understanding how different strains spread and persist, yet current methods to differentiate strains are either unreliable or too costly for routine use. In this study, we developed a standardized multilocus sequence typing system that provides a simple, accurate, and globally accessible way to identify and compare strains of A. paragallinarum. This scheme identified important links between outbreaks at local and regional levels and showed that certain strains persisted over time. By making the scheme available through PubMLST, laboratories worldwide can use a common tool to track and investigate the pathogen. This accessible tool improves disease surveillance, supports outbreak investigations, and helps poultry producers and veterinarians respond more effectively to IC.

Multilocus Sequence Typing

Molecular epidemiology of levofloxacin-resistant Klebsiella pneumoniae and the association of plasmid-mediated quinolone resistance genes with key biological phenotypes.

UNLABELLED: Klebsiella pneumoniae is a major opportunistic pathogen in China, yet the molecular epidemiology of quinolone resistance remains poorly characterized. This study analyzed 2,433 clinical isolates from 37 Chinese hospitals (2018-2022). The overall levofloxacin-non-susceptible (NS) rate was 53.60%, with urinary tract isolates showing higher resistance. Whole-genome sequencing identified 12 plasmid-mediated quinolone resistance (PMQR) genes. Among 1,304 NS strains, 74.54% carried at least one PMQR gene (mainly qnrS, qnrB, and aac(6')-Ib-cr), and 60.20% also had quinolone resistance-determining region (QRDR) mutations. Functional studies revealed diverse phenotypic impacts. Most PMQR genes conferred low-level resistance (minimum inhibitory concentration [MIC] = 1 mg/L), while qnrB52 and qnrB91 caused high-level resistance (MIC = 8-16 mg/L). Notably, qnrB91 reduced biofilm formation, indicating a trade-off between resistance and colonization. Growth assays showed that qnrB52, qnrB91, and qnrS1 inhibited normal growth, whereas qepA1 and qnrS1 enhanced growth under ethanol stress. Most PMQR genes (except qnrB6) attenuated bacterial adhesion. qepA1 promoted intracellular survival in macrophages, suggesting a role in chronic infection. Animal models confirmed that qnrB6, qnrB7, qnrVC6, and aac(6')-Ib-cr significantly enhanced virulence. This study is the first in China to report qnrVC6 and novel gyrA mutations (Ser83Ala/Val, Asp87Phe/His) in K. pneumoniae. It systematically reveals how PMQR genes influence infection by modulating resistance, immune evasion, and pathogenicity. These findings highlight that PMQR genes contribute not only to antibiotic resistance but also to virulence, suggesting that treatment strategies should consider specific PMQR genotypes. This research provides the largest-scale molecular epidemiological data and a theoretical basis for controlling quinolone-resistant K. pneumoniae in China. IMPORTANCE: Quinolone-resistant Klebsiella pneumoniae poses a serious threat to public health, yet the role of plasmid-mediated quinolone resistance (PMQR) genes beyond antibiotic resistance remains underexplored. In this largest-scale multicenter study in China, we analyzed 2,433 clinical isolates and discovered that PMQR genes do more than just confer drug resistance-they also influence bacterial growth, stress survival, biofilm formation, and the ability to evade or persist within host immune cells. Some PMQR genes even enhance virulence in an animal model. These findings challenge the traditional view of resistance genes as mere contributors to drug failure, revealing that they can also shape infection outcomes by altering bacterial behavior. Understanding these dual roles may guide more precise treatment strategies targeting specific PMQR genotypes.

Klebsiella pneumoniae

Molecular epidemiology and genomic characteristics of clinical Acinetobacter baumannii isolates from patients with hospital-acquired pneumonia in China, 2019-2020: a multicentre retrospective study.

BACKGROUND: Carbapenem-resistant Acinetobacter baumannii (CRAB) is a leading cause of hospital-acquired pneumonia (HAP) with high mortality. However, large-scale nationwide data of HAP-causing CRAB in China remain limited. METHODS: Here, we performed a nationwide multicentre retrospective study to characterise the molecular epidemiology and genomic features of 802 A. baumannii isolates from patients with HAP across 33 tertiary hospitals in China during 2019-2020. Antimicrobial susceptibility testing (AST), whole-genome sequencing (WGS), phylogenetic and comparative genomic analysis were used to investigate molecular epidemiology of HAP-causing CRAB strain. Clinical comparative analyses were carried out on data from 500 patients with HAP stratified by distinct antimicrobial susceptibility and genomic profiles, and a Galleria mellonella infection model was utilised for in vivo virulence assessment. FINDINGS: The overall carbapenem resistance rate of A. baumannii was 82.0% (658/802), with marked regional variations. CRAB exhibited high resistance to conventional agents but remained largely susceptible to polymyxin, tigecycline, cefiderocol and sulbactam-durlobactam. Among enrolled patients, CRAB infection was linked to substantially higher mortality (39.0% vs. 17.5%), and multivariate analysis confirmed ICU admission and advanced age as independent risk factors for patients with CRAB infection. Molecular typing revealed STPas2 (96.2%) as the absolutely predominant type; STOxf208, STOxf195, STOxf540, and STOxf369 were the most prevalent Oxford sequence types with obvious geographic stratification and divergent comorbidity profiles among corresponding patients. A total of 654 CRAB isolates harboured carbapenemase genes, with blaOXA-23 dominating at 98.8%. Genomic analysis revealed lineage-specific features: STOxf208 carried more virulence genes, while STOxf540 harboured a broader antimicrobial resistance genes (ARGs). The STOxf208 clone mainly belonged to KL2 (62.1%) and KL7 (36.8%) serotypes, with KL2 strains possessing richer ARGs and virulence factors, and in vivo virulence assays further validated that KL2 strains possessed higher pathogenicity than KL7 strains. INTERPRETATION: This study demonstrates the extremely high prevalence and clonal dominance of CRAB in Chinese patients with HAP, providing critical evidence for clinical treatment, antimicrobial stewardship, and targeted infection control. FUNDING: National Key Research and Development Program of China (2024YFE0106200), National Natural Science Foundation of China (U22A20338, 82502763, W2621007), Zhejiang Provincial Natural Science Foundation of China (LQN25H190006), Zhejiang Provincial Postdoctoral Science Foundation (ZJ2025058).

Acinetobacter baumannii

Effect of repeated mass drug administration on the transmission of yaws: a retrospective genomic epidemiology study.

BACKGROUND: Yaws, a neglected tropical disease caused by Treponema pallidum subspecies pertenue (T p pertenue), has evaded eradication, in part due to a high proportion of asymptomatic cases. Repeated mass drug administration (MDA), whereby an entire population is repeatedly treated irrespective of disease, could provide a solution. Here, we aimed to investigate the effect of MDA on the genomic epidemiology of T p pertenue. METHODS: We conducted a retrospective genomic epidemiology study on samples collected during a cluster-randomised trial of mass administration of azithromycin for yaws eradication in the Namatanai District of Papua New Guinea. Participants were in 38 wards (administrative units encompassing several villages) in three local-level government areas (LLGs). The experimental group received an initial round of MDA followed by two further rounds 6 months and 12 months after the first round. The control group received one round of MDA followed by two rounds of treatment targeting clinical cases and contacts only, on the same schedule as the MDA in the experimental group. A follow-up survey on both groups was done 18 months after the first MDA round. Swab samples were collected at each round from ulcerative and nodular skin lesions, and blood was collected by finger-prick for serological testing at 18 months. Metadata on ulcer size (cm) and duration (days) were recorded at each round, and treponemal and non-treponemal antibodies were recorded at 18 months. Samples from swabs positive for T p pertenue underwent library preparation and whole-genome sequencing. We examined the phylogenetic relationships between genomes, linking them with geospatial and patient metadata to understand the impact of MDA on T p pertenue diversity and transmission. FINDINGS: Swabs collected from 297 individuals with active yaws from April 30, 2018, to Nov 2, 2019, yielded 222 good-quality Tp pertenue genomes. We identified 20 sublineages of T p pertenue in the control group and 21 in the experimental group at the beginning of the study. At the end of the study, there were 13 sublineages in the control group and three in the experimental group, of which two persisted in both groups. Three sublineages not detected at baseline were observed in the control group after commencing MDA. The two sublineages that persisted in both groups had non-synonymous mutations in penicillin-binding proteins. One of these sublineages evolved macrolide resistance in three individuals and was associated with lowered treponemal antibody (p=0&#xb7;0036) and longer ulcer duration (p=0&#xb7;015). Despite the study taking place within a small island, sublineages were geographically clustered, with pairs of samples from the same ward (odds ratio 7&#xb7;1, 95% CI 5&#xb7;7-8&#xb7;8; p<0&#xb7;0001) or neighbouring wards (4&#xb7;3, 3&#xb7;3-5&#xb7;4; p<0&#xb7;0001) more likely to share the same sublineages compared with pairs from different LLGs. Additionally, older individuals were more likely to share sublineages than were younger individuals (1&#xb7;5, 1&#xb7;2-1&#xb7;9; p<0&#xb7;0001). INTERPRETATION: Repeated MDA was successful in reducing and maintaining the genetic diversity of T p pertenue at a low level but was associated with the development of macrolide resistance. Yaws re-emergence after MDA was attributed to multiple sublineages, of which the majority were detected in the population before MDA. Participants within the same ward were more likely to share sublineages than those that were more widely geographically separated, suggesting that re-emergence was driven by local transmission. These findings could inform future yaws elimination strategies. FUNDING: European Research Council, EU, Provincial Deputation of Barcelona, Barber&#xe0; Solid&#xe0;ria Foundation, Wellcome, and Fundaci&#xf3; "la Caixa".

Adolescent

Characterisation of Bordetella pertussis virulence and macrolide resistance in Australia by targeted culture-independent sequencing: a genomic epidemiology study.

BACKGROUND: Bordetella pertussis continues to circulate globally despite widespread vaccination, with a notable epidemic in 2024. Its resurgence is confounded by the emergence of pertactin-deficient, macrolide-resistant B pertussis strains in Asia and Europe, which are under-recognised by conventional diagnostics. We aimed to apply targeted culture-independent next-generation sequencing (tNGS) of respiratory specimens to improve global B pertussis diagnostic capability and genomic surveillance. METHODS: We did a nationwide genomic epidemiology study of B pertussis RT-PCR-positive respiratory specimens that were retrospectively and prospectively collected by diagnostic and public health laboratories in six of seven states and territories of Australia. Specimens underwent tNGS and macrolide-resistant B pertussis-specific PCR, and an opportunistic subset from New South Wales and Queensland were cultured for confirmatory susceptibility testing and whole-genome sequencing. Sequencing data were analysed for genome recovery, virulence profiles, and macrolide resistance mutations, and were compared with international macrolide-resistant B pertussis genomes and ancestral Australian genomes. The performance of the tNGS approach was assessed with logistic regression relative to RT-PCR cycle threshold values, and sensitivity and specificity values were calculated. FINDINGS: 255 respiratory specimens positive for B pertussis were included in the study. 64 (25%) were retrospectively collected between Jan 12, 2012, and Dec 31, 2023, and 191 (75%) were prospectively collected between Jan 1 and Oct 28, 2024. Of these 255 specimens, 148 (58%) yielded near-complete B pertussis genomes through tNGS. Seven co-circulating lineages of B pertussis were documented, including two associated with macrolide-resistance. Eight epidemiologically unrelated and geographically dispersed cases of macrolide-resistant B pertussis with a 23S rRNA 2037A&#x2192;G mutation were identified by tNGS and confirmed by whole-genome sequencing. Three of these were further validated by phenotypic testing. The estimated prevalence of macrolide resistance among Australian cases positive for B pertussis was 4% (eight of 188). INTERPRETATION: tNGS can recover near-complete B pertussis genomes directly from clinical specimens, enabling identification of macrolide resistance mutations and high-resolution phylogenetic analysis. These findings show that tNGS complements PCR-based surveillance by providing genome-wide assessment of resistance, virulence, and genomic diversity in a single workflow. FUNDING: NSW Health Prevention Research Support Program.

Macrolides

Comparison of phylogenetic metrics of transmission between symptomatic and asymptomatic tuberculosis in individuals who were incarcerated in Brazil in 2008-24: a retrospective genomic epidemiology study.

BACKGROUND: Tuberculosis control efforts have traditionally targeted symptomatic individuals; however, the role of asymptomatic cases in sustaining transmission is increasingly recognised. We aimed to quantify the contribution of asymptomatic tuberculosis to recent transmission using genomic and epidemiological data from a high-transmission setting. METHODS: We conducted a retrospective genomic epidemiology study of Mycobacterium tuberculosis isolates collected in Mato Grosso do Sul, Brazil, between Aug 25, 2008, and March 19, 2024. Available isolates underwent whole-genome sequencing. Demographic, clinical, incarceration history, and laboratory metadata were obtained from surveillance records. From Jan 1, 2017, to March 19, 2024, active case finding was conducted in the state's three largest prisons (all male-only facilities), during which sputum samples were collected from individuals irrespective of symptoms and tested using GeneXpert and culture. Comparisons of transmission between individuals with and without symptoms were restricted to individuals who were incarcerated and were identified through active case finding and for whom high-quality, M tuberculosis lineage 4 genomes were available. Metrics of recent transmission included phylogenetic clustering, time-scaled haplotype density (THD), local branching index (LBI), and transmission probabilities inferred using Bayesian Reconstruction and Evolutionary Analysis of Transmission Histories. FINDINGS: 4448 tuberculosis cases were notified in Mato Grosso do Sul in 2008-24. After excluding cases for which M tuberculosis isolates were not available or had low sequencing quality, who had contaminated cultures or mixed infection, or who were infected with non-lineage 4 M tuberculosis, we included 2362 lineage 4 M tuberculosis isolates with high-quality genome sequences. 1849 (78&#xb7;3%) of 2362 isolates were part of a genomic cluster. Among 2362 individuals with tuberculosis, 1137 (48&#xb7;1%) were incarcerated at diagnosis. Of these individuals, 505 were identified through active case finding in three male-only prisons. The median age was 30 years (IQR 25-37); 304 (60&#xb7;2%) had mixed ethnicity, 90 (17&#xb7;8%) were White, 56 (11&#xb7;1%) were Black, 13 (2&#xb7;6%) were Indigenous, and six (1&#xb7;2%) were Asian. 277 (54&#xb7;9%) had symptomatic disease and 228 (45&#xb7;1%) had asymptomatic tuberculosis. There were no significant differences between symptomatic and asymptomatic individuals in phylogenetic clustering (213 [76&#xb7;9%] of 277 vs 195 [85&#xb7;5%] of 228; p=0&#xb7;37), THD (median 0&#xb7;39 [IQR 0&#xb7;06-0&#xb7;62] vs 0&#xb7;50 [0&#xb7;09-0&#xb7;65]; p=0&#xb7;12), or LBI (0&#xb7;00863 [0&#xb7;00810-0&#xb7;00988] vs 0&#xb7;00871 [0&#xb7;00829-0&#xb7;01020]; p=0&#xb7;088). Bayesian transmission trees showed no significant difference in the number of secondary infections inferred from symptomatic compared with asymptomatic individuals (p=0&#xb7;56). These findings were consistent across genomic clusters and robust to model assumptions. INTERPRETATION: We identified no differences in transmission between individuals who were symptomatic and those who were asymptomatic using multiple genomic measures. In this high-transmission setting, where systematic screening is implemented, our findings indicate that asymptomatic tuberculosis substantially contributes to tuberculosis transmission at the population level. These results suggest that symptom-based case detection alone is likely to be insufficient to interrupt transmission and highlight the importance of expanded screening strategies in high-risk populations. FUNDING: US National Institutes of Health and the Brazilian National Research Council (CNPq).

Humans

First nationwide full-genome characterisation of human-derived Andes virus in Chile: a retrospective genomic epidemiology study.

BACKGROUND: Andes virus (ANDV) is the only hantavirus known to transmit between humans and causes hantavirus cardiopulmonary syndrome in Chile and Argentina. In Chile, ANDV genomic diversity remains incompletely characterised. This study aimed to characterise the genetic diversity, geographical structure, and molecular signatures of ANDV using human clinical samples collected over a 13-year period (2011-24). METHODS: We conducted a retrospective genomic epidemiology study of ANDV infections in Chile. Clinical samples from patients with confirmed ANDV, collected between March 9, 2011, and June 27, 2024, were analysed and sequenced. Clinical and epidemiological data were obtained from diagnostic laboratories and surveillance programmes. Consensus sequences for the S, M, and L segments were generated, and genetic clustering and divergence were assessed using phylogenetic inference and variant calling. FINDINGS: We analysed clinical samples from 58 infected individuals and identified two major genomic variants of ANDV with distinct geographical distributions, defined by regionally structured patterns of nucleotide and amino acid substitutions across the S, M, and L segments: ANDV Chi-North (central Chile) and ANDV-South (southern Chile). No consistent clustering by clinical severity was observed, and no recurrent non-synonymous substitutions were uniquely associated with severe disease. Substitutions previously associated with person-to-person transmission in outbreaks in Argentina were not consistently observed in Chilean sequences, including in four person-to-person transmission cases. Although some substitutions described in ANDV-like viruses were present in the Chi-North lineage, this lineage remained phylogenetically distinct and geographically restricted to central Chile. INTERPRETATION: To our knowledge, this study provides the first nationwide genomic characterisation of human-derived ANDV in Chile. The identification of geographically structured variants indicates that ANDV diversity in Chile is driven by regional diversification rather than clinical outcome. The absence of consistent amino acid signatures associated with disease severity or person-to-person transmission suggests that these phenotypes are unlikely to be explained by viral genetic variation alone. These findings refine current understanding of ANDV evolution and highlight the need for continued integrated genomic surveillance in endemic regions. FUNDING: Agencia Nacional de Investigaci&#xf3;n y Desarrollo de Chile and National Institutes of Health.

Humans

Epidemiological status of bovine viral diarrhea virus in water buffalo (Bubalus bubalis): A global systematic review and meta-analysis.

Bovine viral diarrhea virus (BVDV) remains a neglected viral disease in water buffalo despite its significant economic impact in production systems. Although limited epidemiological studies have been reported worldwide, the serostatus and active infection in buffalo have not been systematically reviewed. A systematic review and meta-analysis were conducted to estimate BVDV prevalence in water buffalo and identify associated epidemiological factors. Relevant studies published up to January 31, 2026, were retrieved from five electronic databases. A total of 49 studies were identified from 15 different countries were found for inclusion. A random-effects model was used to estimate pooled-prevalence and assess heterogeneity among studies. A meta-analysis of 37 studies (9270 buffalo) estimated a pooled BVDV seroprevalence of 30.5%, while analysis of 16 studies (7189 animals) indicated an antigen prevalence of 16.5%. Continent-wise analysis revealed the highest BVDV seroprevalence in South-America (44.0%), while antigen prevalence was highest in Africa (21.2%) followed by Asia at 12.2%, and no BVDV data reported from North-America. Among the different countries, the highest BVDV seroprevalence was detected in Turkey (61.6%) and Argentina (59.0%), while antigen prevalence was highest in Egypt (21.2%), with lower estimates in Brazil (11.8%) and Iraq (11.3%). Notably, high heterogeneity (I2&#xa0;>&#xa0;90%) was observed in the all-pooled estimates, indicating variations in sampling period, age, sex, sample source and types, diagnostic methods, production-system, and study quality. These findings demonstrate the widespread presence of BVDV in water buffalo populations and indicate the need for targeted control strategies to mitigate its impact on health and productivity.

Animals

Accounting for contact tracing in epidemiological birth-death models.

Phylodynamics bridges the gap between classical epidemiology and pathogen genome sequence data by estimating epidemiological parameters from time-scaled pathogen phylogenetic trees. The models used in phylodynamics typically assume that the sampling procedure is independent between infected individuals. However, this assumption does not hold for many epidemics, in particular for such sexually transmitted infections as HIV-1, for which contact tracing schemes are included in health policies of many countries. We extended phylodynamic multi-type birth-death (MTBD) models with contact tracing (CT), and developed a simulator to generate trees under MTBD and MTBD-CT models. We proposed a non-parametric test for detecting contact tracing in pathogen phylogenetic trees. Its application to simulated data showed that it is both highly specific and sensitive. For the simplest representative of the MTBD-CT family, the BD-CT(1) model, where only the last contact can be notified, we solved the differential equations and proposed a closed form solution for the likelihood function. We implemented a maximum-likelihood program, which estimates the BD-CT(1) model parameters and their confidence intervals from phylogenetic trees. It performed accurate parameter inference on BD and BD-CT(1) simulated data, and detected contact tracing in HIV-1 B epidemics in Zurich and the UK. Importantly, we showed that not accounting for contact tracing when it is present, leads to bias in parameter estimation with the BD model (overestimation of the becoming-non-infectious rate). This bias is also present, but greatly reduced, when the BD-CT(1) model is used on data where multiple contacts can be notified. Our CT test, MTBD-CT tree simulator and BD-CT(1) parameter estimator are freely available at GitHub (evolbioinfo/treesimulator and evolbioinfo/bdct).

Contact Tracing

Epilepsy: Bridging Epidemiological Landscapes, Molecular Mechanisms, and Emerging Precision Therapeutics.

Epilepsy ranks among the most prevalent neurological disorders worldwide, and recent years have witnessed significant advancements in understanding its epidemiological features, pathophysiological mechanisms, diagnostic methodologies, and therapeutic approaches. This review systematically examines the epidemiology of epilepsy, highlighting pronounced regional and population-based disparities, particularly the substantial treatment gap observed in low-income countries. Regarding pathogenesis, epilepsy development involves aberrant ion channel function, neuroinflammatory processes, dysregulation of the mTOR signaling pathway, and genetic predispositions. Diagnostic innovations, including ultra-high field magnetic resonance imaging, artificial intelligence-enhanced electroencephalogram analysis, and liquid biopsy techniques, have markedly enhanced the precision of epileptogenic focus localization and etiological identification. Genetic investigations have uncovered numerous epilepsy-associated genes, thereby underpinning the advancement of targeted therapies. Therapeutically, novel antiepileptic drugs, neuromodulation modalities such as vagus nerve stimulation and deep brain stimulation, alongside gene therapy, have expanded treatment options for refractory epilepsy. Nonetheless, global epilepsy management continues to confront challenges including limited drug accessibility, social stigma, and pharmacoresistance. The future trajectory emphasizes individualized and precision medicine approaches, integrating genomics, biomarker discovery, and intelligent monitoring technologies to foster comprehensive improvements in epilepsy diagnosis and treatment.

epidemiology

Molecular epidemiological characteristics of H9N2 subtype avian influenza virus in the external environment of western Zhejiang, China, 2014-2025.

OBJECTIVE: To elucidate the epidemiological distribution patterns of avian influenza virus (AIV) in the external environment of western Zhejiang from 2014 to 2025, analyze the molecular epidemiological characteristics of the H9N2 subtype, and assess its public health risks. METHODS: According to the Zhejiang Provincial Surveillance Program for Avian Influenza in Occupationally Exposed Populations and External Environments, real-time RT-PCR was used to detect AIV subtypes in environmental specimens. H9N2-positive samples with cycle threshold values <30 were inoculated into specific pathogen-free (SPF) embryonated chicken eggs for virus isolation, followed by whole-genome sequencing and bioinformatics analysis for phylogenetic and molecular characterization. RESULTS: A total of 7,762 specimens were tested from 2014 to 2025, with an overall positivity rate of 34.64% (2,689/7,762) for AIV. Significant differences in positivity rates were observed in seasons, regions, sampling sites, and specimen types (all p&#x202f;<&#x202f;0.001). AIV activity peaked in winter and spring, with the highest rates detected in live poultry markets and chopping board swabs. The H9 was the predominant subtype, with co-circulation of multiple subtypes. All 48 H9N2 subtype isolates belonged to the G57 genotype, with the hemagglutinin (HA) and neuraminidase (NA) genes falling into the Y280-like branch, while the internal genes exhibited a mosaic pattern combining G1-like and F/98-like lineages. Molecular characterization analysis revealed multiple mammalian adaptive mutations, involving alterations in receptor-binding sites (T163N, H191N, T197D, T198V, Q234L, Q235M), antigenic epitopes (D280G, N285S), and glycosylation sites (218NRTF, 313NCSK). NA stalk deletion (62-64 aa), along with multiple mutations in the hemadsorption site (E/K368N, D369S/G, D401G/V, N402D, W403L/R, Q432H). Additionally, multiple key amino acid substitutions were also identified in the internal proteins. CONCLUSION: The external environment in western Zhejiang exhibits a high prevalence of AIVs with pronounced spatiotemporal clustering. H9 was the dominant subtype and co-circulated with multiple subtypes, with live poultry markets and slaughterhouses identified as high-risk settings. The H9N2 subtype AIV has accumulated multiple mammalian adaptive mutations, and exhibits genetic linkages across eastern Chinese provinces. These findings collectively underscore the need for an integrated One Health surveillance and early-warning system to reduce the risk of human infections with avian influenza.

Influenza in Birds

Mortality and causes of death in the Korean Genome and Epidemiology Study (KoGES), 2001-2023.

The Korean Genome and Epidemiology Study (KoGES) is a large prospective cohort study established to investigate determinants of chronic disease. To evaluate overall and cause-specific mortality, KoGES records were linked to the official Causes of Death Statistics compiled by Statistics Korea. Of 211,562 participants the KoGES population-based cohorts, 211,428 were successfully linked to official mortality data through December 31, 2023, using resident registration numbers. Over a mean follow-up of 14.9 years, the linked cohort had an overall mortality rate of 5.8 deaths per 1,000 person-years; the rate was higher among men than among women (9.6 vs. 3.9 deaths per 1,000 person-years). Malignant neoplasms, heart disease, and cerebrovascular disease were the leading causes of death. As the cohort aged, deaths from causes such as pneumonia increased substantially, a pattern consistent with national mortality statistics. This linked dataset provides a basis for longitudinal analyses of chronic disease progression, survival outcomes, and cause-specific mortality using repeated epidemiologic measurements collected over more than 2 decades of follow-up.

Causes of death

Moraxella&#xa0;species isolated from blood cultures in Europe (MORAXEu): a multicentre study of epidemiology and antimicrobial susceptibility&#xa0;with complementary phylogenomic analysis of publicly available genomes.

INTRODUCTION: Moraxella species are fastidious Gram-negative bacteria capable of causing opportunistic infections, including bloodstream infections, especially in immunocompromised patients. Data on their epidemiology, antimicrobial susceptibility, and phylogenomics in Europe remains limited. METHODS: We conducted a multicentre, retrospective, observational study across 56 European hospital centres between January 1st&#xa0;2020 and December 31st&#xa0;2024. All Moraxella species isolated from blood cultures (BCs) were included. Species distribution and antimicrobial susceptibility profiles were analysed. We also performed a phylogenomic analysis of Moraxella genomes deposited in GenBank. RESULTS: A total of 709 Moraxella isolates were included. Moraxella osloensis (61.1%; n&#x2009;=&#x2009;433/709) and Moraxella catarrhalis (20.4%; n&#x2009;=&#x2009;145/709) were the most frequently identified species, followed by Moraxella nonliquefaciens (6.5%; n&#x2009;=&#x2009;46/709) and Moraxella atlantae (4.8%; n&#x2009;=&#x2009;34/709). Species distribution differed by age. M. catarrhalis was predominant in paediatric patients, whereas M. atlantae was more common in adults. Most isolates showed&#x2009;>&#x2009;90% susceptibility to amoxicillin/clavulanate, cefotaxime, fluoroquinolones, and trimethoprim/sulfamethoxazole. Cefotaxime resistance in M. osloensis was more frequent in adults than in children (49% vs. 8%, p&#x2009;=&#x2009;0.009). Phylogenomic analysis demonstrated the distinction of a core Moraxella group from the divergent Faucicola lineage, with M. osloensis and M. atlantae clustering within the latter. CONCLUSIONS: The epidemiology of Moraxella species from BCs in Europe showed age-group-specific differences in species distribution and generally favourable antimicrobial susceptibility patterns. Phylogenomic data corroborated recent taxonomic revisions, highlighting the need for improved diagnostics, harmonized nomenclature and sustained surveillance to inform management and stewardship of Moraxella bacteraemia.

Faucicola

History and clinical epidemiology of NF2-related schwannomatosis.

NF2-related schwanomatosis (NF2-SWN) (previously Neurofibromatosis 2) as characterised by bilateral vestibular schwannomas (VS) was first described in 1822. However, due to the erroneous conflation of individuals with bilateral eighth nerve tumours with von Recklinghausen disease (currently Neurofibromatosis 1, NF1) in 1917 the literature was confusing for much of the 20th century. Even when the conditions were separated officially in 1987 (with separate localisation of the genes), NF2-SWN remained classified as a neurofibromatosis despite the tumours pathognomonic for NF1, neurofibromas, not being a feature of NF2-schwannomatosis. It is only in 2022 that NF2-SWN was correctly delineated as a schwannomatosis. The epidemiology of NF2-SWN has only been possible to delineate after the separation of NF2-SWN from the much more frequent nerve sheath predisposing tumour condition NF1. Two research groups have published on the birth prevalence and population prevalence of NF2-SWN in the UK and Finland. The most highly ascertained assessment of NF2-SWN cases from the Manchester region of England (population 4.8&#xa0;million) gave a diagnostic prevalence of 1 in 50,500 and calculated birth prevalences of 1 in 27,956 respectively. However, an updated prevalence across England in 2024 (population 55&#xa0;million) gave a prevalence of at least 1 in 58,000. NF2-SWN usually presents with bilateral vestibular schwannoma, but can present with meningioma or spinal tumour or ophthalmic features before a VS diagnosis or with a unilateral VS and other tumours and rarely with a unilateral VS alone. Molecular testing is now extremely helpful in confirming the diagnosis of mosaic (present in up to 50% of de novo cases) versus germline NF2 and distinguishing from other tumour predisposition conditions especially in childhood or cases with less common presentation. This chapter summarises the clinical epidemiology of NF2-SWN differentiating the condition from the overlapping non NF2-SWN.

Humans

Unraveling the epidemiological and dispersal dynamics of the 2024-2025 chikungunya virus epidemic on R&#xe9;union Island.

R&#xe9;union Island experienced a massive chikungunya virus epidemic in 2024-2025, with >54,000 confirmed cases. This is the second major chikungunya epidemic on the island, following the first one that peaked 20 years ago. It has been asserted that this new outbreak finds its origin in a single introduction event into the island, offering an opportunity to exploit viral genomic data to understand the epidemiological and dispersal dynamics of the introduced transmission chain. We sequenced >3,000 viral genomes collected during the epidemic. Harnessing this genomic dataset, we used several phylogeographic and phylodynamic approaches to unravel the paths taken by the transmission chain and the external factors that might have impacted its dispersal and epidemiological dynamics on the island. Our analyses highlight a dispersal pattern in line with a gravity-model dynamic with viral transition events being more frequent from and toward more populated areas. Our analyses reveal that the transmission chain was overall spatially intermixed, with frequent exchanges among residential areas. In addition, we show that the temporal dynamic and intensity of the epidemic were associated with climatic variables, namely temperature and precipitation. Our results also show that in theory, the population immunity-resulting from this epidemic and the previous one (2005-2006)-could be sufficient to explain on its own the decrease in the transmission rate that led to the end of the epidemic. While a short-term resurgence cannot be excluded, the risk of a large-scale circulation of the virus in the human population appears therefore relatively limited in the upcoming seasons.

Reunion

Global epidemiology of diabetes and prediabetes in lean or non-obese patients with NAFLD: a systematic review and meta-analysis.

BACKGROUND: The presence of diabetes increases the risk of adverse outcomes of patients with non-alcoholic fatty liver disease (NAFLD) even in those with lean or non-obese NAFLD. However, the epidemiological data regarding the prevalence of diabetes and prediabetes in lean or non-obese NAFLD populations remain limited. We assessed the global epidemiology of diabetes and prediabetes in lean or non-obese patients with NAFLD. METHODS: Published studies were searched in PubMed, EMBASE, Cochrane Library, and Web of Science databases from the inception of the databases to October 2024. The pooled global prevalence of diabetes or prediabetes in patients with NAFLD was evaluated using random-effects meta-analysis. Subgroup meta-analysis and meta-regression were used to investigate potential sources of heterogeneity. RESULTS: A total of 54 studies involving 146,714 patients with non-obese or lean NAFLD were included. The pooled global prevalence of diabetes among patients with lean or non-obese NAFLD was 15.6% (95% CI 10.8%-22.7%). Studies from South America reported the highest prevalence (41.3%, CI 39.1%-43.5%). Meta-regression models showed that geographic region and mean age (p&#x2009;<&#x2009;0.05) were associated with the were associated with the prevalence of diabetes, jointly accounting for 51.61% of the heterogeneity. The global prevalence of prediabetes among patients with lean or non-obese NAFLD was 22.9% (95% CI 12.5%-41.9%) with the highest prevalence reported in studies from Europe (34.4%, CI 23.0%-51.4%). Meta-regression models showed that geographic region and country (p&#x2009;<&#x2009;0.05) were associated with the prevalence of prediabetes, jointly accounting for 73.65% of the heterogeneity. CONCLUSION: The pooled global prevalence of diabetes and prediabetes were 15.6% and 22.9% in lean or non-obese patients with NAFLD, respectively. These findings suggest the importance of diabetes screening in these patients.

Humans

Performance of seven carbapenemase detection assays in Pseudomonas aeruginosa across different epidemiological settings: a multicenter cross-sectional study.

The detection of carbapenemases in Pseudomonas aeruginosa remains challenging due to a great variety of other resistance mechanisms, and most laboratories, therefore, do not test for them. This study aimed to comparatively evaluate seven phenotypic carbapenemase detection assays across three epidemiological settings. A total of 320 P. aeruginosa isolates from three German centers with varying carbapenemase prevalences (5.8%-51.4%), including 113 carbapenemase-producing isolates carrying VIM-2 (n = 58), NDM-1 (n = 19), and GIM-1 (n = 16), underwent whole-genome sequencing as reference to assess seven phenotypic carbapenemase-detection tests: modified- and modified-zinc-supplemented carbapenem inactivation method (mCIM and mzCIM), simplified carbapenem inactivation method (sCIM), Carba NP, imipenem-cloxacillin test (IC-4000), and two imipenem-EDTA disk assays. Of all confirmation assays, mzCIM and sCIM showed the best overall performance for carbapenemase detection (sensitivity/specificity: 100%/94.2% and 99.1%/92.8%), followed by mCIM (93.8%/96.1%). Carba NP achieved the highest specificity (99.0%), but the lowest sensitivity (85.8%). EDTA-based assays and IC-4000 were highly sensitive (96.5%-100%) but less specific (79.7%-87.0%). Negative predictive values were consistently high (&#x2265;98%-100%) across all assays and prevalence settings, whereas positive predictive values varied (72.5%-98.0%). Both mzCIM and sCIM exhibited robust performance for carbapenemase detection in P. aeruginosa, representing the most suitable approach across diverse epidemiological settings. Their high negative predictive values indicate that these assays are particularly effective for ruling out carbapenemase production. Furthermore, both assays are cost-effective, simple to perform, and can be readily implemented in any routine microbiology laboratory.IMPORTANCEThis study provides comparative diagnostic accuracy data for seven phenotypic carbapenemase detection assays in Pseudomonas aeruginosa (PA) across different prevalence settings. Modified-zinc-supplemented carbapenem inactivation method (mzCIM) and simplified carbapenem inactivation method (sCIM) are the most robust screening tools and show that local carbapenemase-producing P. aeruginosa (CP-PA) prevalence substantially influences the utility of all evaluated assays.

CIM