Emerging Infectious Diseases

Low pathogenic avian influenza A(H7N7) virus detected in a poultry worker in Taiwan, 2026 was related to viruses circulating in Asian wild birds and possessed PB2 E627K, a mammalian adaptation marker. Enhanced surveillance for H7 viruses in poultry and rapid characterization of human cases are essential to assess pandemic potential.

BackgroundHuman Mastadenovirus B (HAdV-B) causes ocular and respiratory infections and is capable of causing outbreaks in healthcare settings. HAdV-B114, a recombinant genotype only formally recognised in 2023, has been reported predominantly from Germany, the USA, China and Japan; genomic data from UK clinical settings remain limited. This study analysed 68 HAdV-B whole genomes from ocular and respiratory-associated samples collected at a Nottingham hospital across the pre- and post-COVID-19 restriction periods (2017-2023). MethodsClinical samples typed positive for HAdV-B by partial hexon Sanger sequencing were selected for whole-genome sequencing using a novel overlapping PCR amplicon strategy, sequenced on the Oxford Nanopore Technologies PromethION platform. Phylogenetic and pairwise difference analyses were used to characterise genotype composition and genomic relatedness. SimPlot and amino-acid comparison characterised divergence between sub-lineages. ResultsWhole-genome phylogenetics confirmed that two species B genotypes were detected in Nottingham University Hospitals between 2017-23: HAdV-B114 (n=56) and HAdV-B7 (n=12). HAdV-B114 was detected before and after COVID-19 restrictions, with an increase in 2022-2023, consistent with post-restriction expansion of a pre-existing lineage. Pairwise difference analysis identified 24 genomically identical B114 sequences; associated metadata argued against a single nosocomial transmission chain interpretation, with the pattern more consistent with repeated detection of a widely circulating community strain, with the possibility of localised onward transmission. Within the B114 clade, multiple monophyletic groups were identified by whole-genome phylogenetics. ConclusionsThis study adds whole-genome resolution to the existing UK HAdV-B114 data, demonstrates the utility of WGS for clinical adenovirus surveillance and shows the benefits of combining epidemiological data with genomic analysis.

Since 2020, highly pathogenic avian influenza (HPAI) A(H5Nx) clade 2.3.4.4b viruses have spread globally, causing extensive outbreaks in domestic and wild birds. Increased circulation has resulted in frequent spillover to mammals, and occasional mammal-to-mammal transmission. Although human infections remain rare, the zoonotic potential of these viruses continues to be a public health concern. We investigated six cases of HPAI in red foxes (Vulpes vulpes) in Norway during 2022-2024 and identified infections with H5N1 and H5N5 viruses. Pathological and virological investigations demonstrated systemic infection, with prominent lesions in the brain and/or lungs. Phylogenetic analyses showed high similarity between viruses detected in foxes and those concurrently circulating in wild birds. The mammalian adaptation marker PB2:E627K was identified in one H5N1 virus and as a minority variant in a second H5N1 virus.

Bundibugyo ebolavirus (BDBV) is causing an ongoing outbreak in the Democratic Republic of Congo (DRC) with no licensed vaccine available. Recent reports have shown the presence of BDBV-cross-reactive antibody responses in humans vaccinated against the related Ebola virus (EBOV). Here, we used an IFN-{gamma} ELISpot assay to assess T cell responses against the EBOV, BDBV and SUDV glycoproteins in clinical trial participants vaccinated with the licensed VSV-EBOV vaccine. We could show that BDBV-cross-reactive T cell responses are detectable in the majority of individuals and that conserved regions within the glycoprotein are targeted. In the absence of a BDBV-specific vaccine, these data support efficacy trials of the VSV-EBOV vaccine during the current outbreak.

Background: Filoviruses, specifically Ebola virus (EBOV), Bundibugyo virus (BDBV), and Marburg virus (MARV), have been the etiologic agents of multiple outbreaks of severe disease in the Democratic Republic of the Congo (DRC). Two EBOV-specific vaccine regimens have been approved for use in outbreak scenarios, including the Ad26.ZEBOV/MVA-BN-Filo (Zabdeno/Mvabea) two-dose vaccine, where the MVA-BN-Filo booster dose contains EBOV, MARV, and Sudan (SUDV) virus glycoproteins (GPs) and the nucleoprotein from Tai Forest virus. While long-term immunogenicity of up to two years has been found in clinical trial settings, limited real-world data exists. Methods: Using a multiplexed immunoassay, samples (n=698 at baseline) collected in Mbandaka, Equateur province, DRC, between September 2023 and October 2024 were assessed for seroreactivity to six filovirus antigens (1 BDBV, 2 EBOV, 2 MARV, and 1 SUDV) at three distinct periods: baseline/pre-vaccination, 6-8 weeks post-first dose (Zabdeno), at booster administration (Mvabea), and one-year post-boost dose. Results: Substantial filovirus seroreactivity was found at baseline, with 48.7% (n=340/698) of individuals being seroreactive to at least one virus antigen. High baseline seroreactivity was found against BDBV GP (31.1%, n=217/698), with lower baseline seroreactivity to EBOV GP (15.5%, n=106/698), comparatively. Overall EBOV GP seroreactivity increased to 66.8% (n=376/563) at one year-post vaccine boost and 57.6% (n=250/434) of participants were seroreactive. Despite the booster dose inclusion of SUDV GP and MARV GP, there were no substantial increases in reactivity against either antigen at subsequent timepoints. Overall filovirus seroreactivity increased at all timepoints for the entire cohort, although filovirus reactivity decreased over the study period for those who were seroreactive at baseline. Findings: These data highlight detection of significantly elevated seoreactivity to EBOV GP following first-dose administration of Ad26.ZEBOV, which remained relatively stable one-year post-booster dose administration. Additionally, this study identifies high levels of baseline seroreactivity to BDBV GP despite no previous documented outbreaks in this region of DRC. These data suggest that vaccination with the Ad26.ZEBOV-MVA-BN-Filo vaccine induces stable seroreactivity against EBOV GP, but not to other filovirus antigens.

Background Ecological surveillance indicates (regional) establishment of West Nile virus (WNV) and Usutu virus (USUV) in the Netherlands. However, the incidence of human infections remains unknown. Methods We identified WNV and USUV infections in the Netherlands in 2020-2023, using a longitudinal, nationwide population-based cohort, applying a two-tiered serology approach based on protein micro-array and virus neutralization. IgG data were used to estimate overall seroprevalence and infection incidence, and to study antibody longevity. Study set-up enabled tracking of the period of seroconversion and linking of self-reported travel history. The analyses took account of the survey design and weights were incorporated to match the Dutch population distribution following census data. Findings Among 4290 participants, we identified 113 probable WNV and/or USUV cases, including 55 seroconversions. Thirty-six cases were confirmed by antibody neutralization, of which 12 seroconverted. Six confirmed seroconverters were identified as autochthonous infections. The overall weighted seroprevalence was estimated at 0.54% (0.21-0.87%) for WNV and 0.25% (0.09-0.40%) for USUV. The weighted incidence for autochthonous WNV and USUV infection was estimated as respectively 0.06% (95% CI 0-0.12%) and 0.04% (95% CI 0-0.09%). Interpretation The estimated infection incidence and seroprevalence of WNV and USUV indicate a substantial underdiagnosis of clinical cases in the Netherlands in 2020-2023. These observations highlight the need for increased awareness among physicians to identify cases and the need for continued paired syndromic-laboratory surveillance for these viruses.

Routine facility-based testing for hepatitis C virus (HCV) remains underutilised in India despite national screening policy. WHO has recommended HCV self-testing (HCVST) since 2021 to increase access to testing services. This study evaluated the HCVST by assessing its reach and uptake in urban-slum communities within Haridwar, Uttarakhand, India. The implementation study (CTRI/2023/07/054590) took place between 12th July 2023 and 31st August 2024. Three Primary Healthcare Centre (PHC) catchment areas were assigned to deliver either (1) facility-based HCVST, (2) home-based HCVST, or (3) standard of care (SoC). Facility-based delivery involved trained users offering kits to patients visiting the PHC (Site 1: Jwalapur 1), whereas home-based delivery (Site 2: Jwalapur 2) involved trained users and ASHAs approaching community households selected via a KISH grid. Primary outcomes were OPD-footfall standardized operational reach; the proportion offered testing out of the PHC catchement areas footfall, and uptake (acceptance among those offered). Secondary analysis explored demographic and behavioural predictors of those that refused to test. Of 7,091 outpatient department (OPD) footfall, 724 (10.2%) individuals were offered HCVST at intervention sites, of which 465 (64.2%) agreed to self-test. Operational reach was 17.8% (393/2,212; 95% CI: 16.2 to 19.5%) through the facility-based intervention and 14.4% (331/2,296; 95% CI: 13.0 to 15.9%) in the home-based intervention.HCVST uptake was higher through the home-based model (71.9%, 238/331, 95% CI: 66.7 to 76.7%) than in the facility (57.8%, 227/393, 95% CI: 52.7 to 62.7%). At the SoC site, only 11 individuals received standard of care HCV testing. The study HCV positivity was 1.1% (5/465; 95% CI: 0.35% to 2.49%): with four testing positive at the facility site (4/227), one at the community site (1/238), and none at the SoC site (0/11). Men were more likely to refuse HCVST than women (OR 0.54, 95% CI 0.37 to 0.78, p=0.001).Participants in the facility-based model had 1.87 times higher odds of refusal compared to those in the home-based delivery model. There is minimal routine HCV testing in the OPD setting of Urban PHCs despite national screening policy. HCVST improved testing coverage and uptake in urban slums compared to SoC. However, HCV positivity was low overall, suggesting that untargeted screening - whether facility-based or home-based - may identify few infections without additional strategies to reach higher-risk populations.

Background: Optimising sampling frames for genomic surveillance of E. coli and Klebsiella may support interventions to mitigate bloodstream infections (BSIs), but approaches to estimating sample size and how these relate to bacterial population diversity at multiple genetic levels (strain/plasmid/antimicrobial resistance genes [ARGs]) are lacking. Methods: Using systematically collected, regionally-stratified, whole genome sequencing data from a 6-month genomic survey of English E. coli/Klebsiella BSI isolates (n=1,939; NEKSUS), we used Bayesian approaches to estimate the sample sizes required to capture genetic diversity at strain- (MLST, fastBAPS clusters), plasmid- and ARG-levels, using two diversity measures: 'coverage' (i.e. proportion of the bacterial population/plasmids/ARGs represented by features observed in the sample), and the number/proportion of unique features observed at varying surveillance sample sizes. Our method is available as a user-friendly R Shiny application, EpiSENTRY (https://01a0c3dd-90d2-e597-58a5-51391a468387.share.connect.posit.cloud/). Findings: Randomly sampling 1,400 E. coli/Klebsiella BSI isolates each achieved [≥]80% coverage of bacterial lineages and ARGs (i.e. capture features constituting [≥]80% of the population) at 95% certainty, but captured lower proportions of unique features (28% MLSTs, 59% fastBAPS clusters, 19% plasmid subcommunities, and 57% ARGs for E. coli; 49%, 87%, 50% and 83% for Klebsiella, respectively). Sample sizes required for 80% coverage of E. coli plasmid populations were higher than MLSTs (1,928 [95% CrI: 1,837-2,025] vs 1,351 [1,230-1,472]), while for Klebsiella, estimates were lower for plasmids (1,115 [1,052-1,181] vs 1,422 [1,331-1,515] for MLSTs). Lower sample sizes adequately captured 80% coverage of fastBAPS clusters and ARGs (649 [575-727] and 27 [23-30], respectively, for E. coli; 113 [84-145] and 83 [72-96] for Klebsiella), due to feature-specific frequency distributions. Klebsiella BSIs were more diverse than E. coli, with sampling 10.9% vs 3.2% of total annual BSIs in England needed to reach 80% MLST coverage. Plasmid populations and Klebsiella MLSTs were region-specific, emphasising the need for regionally-representative sampling. Interpretation: Bayesian analysis facilitates estimates of context-specific genomic surveillance sample sizes. Cost-effective targets for coverage require further optimisation.

Background State-level estimates of hepatitis C virus (HCV) prevalence are needed to guide resource allocation and to provide a baseline against which to measure progress toward elimination goals. Population prevalence is not directly observable, requiring estimation from indirect data sources. Methods We adapted a Bayesian spatial integrated abundance model to estimate state-level HCV prevalence during 2017-2020 across 48 states and the District of Columbia. The model integrated six HCV-related outcomes: acute and chronic surveillance cases, HCV-related deaths, observations of HCV in [MarketScan] administrative claims data, diagnoses of HCV in Medicaid recipients, and treatment with direct-acting antivirals in Medicaid recipients. Estimates were anchored to a national prevalence estimate, and the model accounted for data source-specific selection, heterogeneity in HCV risk factors across states, and geospatial correlation. Results Estimated average prevalence was 1.32% (95% credible interval [CrI]: 0.94%-1.80%), corresponding to 3.33 million (95% CrI: 2.37-4.65 million) adults with HCV infection across 48 states and DC. State estimates ranged from 0.74% in North Dakota to 2.22% in Oklahoma (median state-specific prevalence, 1.27%), with higher prevalence concentrated in South Central states, Appalachia, and the West, and the lower prevalence in the upper Midwest, Southeast, and New England. Ten states accounted for 56% of estimated infections. Estimates were stable in sensitivity analyses (most differences <1 percentage point). Conclusions These estimates quantify state-level HCV burden prior to the 2021 federal expansion of HCV surveillance funding, providing a baseline for monitoring elimination progress. Geographic variation indicates that resource needs will differ by jurisdiction.

The emergence of a dominant poultry-associated strain of Campylobacter jejuni in New Zealand coincided with a multi-year epidemic of human campylobacteriosis. This was characterised by an increase in cases to 2006, when one of the highest national case-rates in the world was recorded, followed by a rapid decline attributed to interventions in the poultry industry. The strain belonged to an internationally rare multilocus sequence type, ST474 - a member of Clonal Complex (CC) 48 - that was highly prevalent in both poultry and human cases in New Zealand but was also identified in other samples. ST474 isolates from humans, animal reservoirs and environmental water samples were collected between 2005 and 2019 and whole genome sequenced (N=443). Isolates from a 2018/9 case-control study of campylobacteriosis in New Zealand were included for genomic comparisons with other sequence types and CCs. This presented an opportunity to examine the genomic epidemiology of a single, relatively recently emerged lineage of C. jejuni, and improve our understanding of drivers of emergence and persistence in a relatively isolated ecosystem. Six subpopulations (clades) of ST474 were identified and these varied in terms of their host association, persistence, patterns of homologous recombination, and complement of mobile genetic elements, including plasmids and chromosomally integrated elements. Clade E was associated with a single poultry supplier in the initial epidemic phase and accounted for 34.5% of human cases. Clade F emerged from a declining Clade E after the peak in human cases and was also associated with poultry. The emergence of Clade F was accompanied by the loss of integrated element CJIE5 and the acquisition of multiple blocks of recombination, likely from diverse ancestral C. jejuni lineages, and the loss of the methionine biosynthesis operon metAB. In contrast, Clades A-D were detected at low frequencies in human cases over the 14-year period of surveillance and were associated with multiple hosts. This longitudinal study sheds light on the evolutionary processes that result in strain emergence and differentiation, highlighting the role of horizontal gene transfer in the evolution and adaptation of this pathogen to new niches, and the subsequent impact on public health.

Background. Nigeria's reported Lassa fever case fatality ratio (CFR) rose from 18.9% at week 23 of 2025 to 25.0% in 2026, prompting concerns over failing clinical care. Because surveillance artefacts can also alter CFRs, candidate mechanisms that published data can resolve were identified and evaluated. Methods. This ecological study extracted weekly state-level counts from 474 Nigeria Centre for Disease Control and Prevention situation reports (2017-2026). Per a pre-specified plan, years were compared at phase-matched points, year-on-year CFR changes were decomposed into within-state and between-state components, and tipping-point ascertainment shifts calculated. Weekly incident and cumulative published totals were compared post hoc. Findings. Of 11 candidate mechanisms, 2 could be evaluated fully and 5 in part. On weekly incident counts, 2026 did not differ from 2025 at the phase-matched midpoint (+0.3 percentage points, 95% CI -5.0 to 7.6); within-state (-1.1, 95% CI -4.7 to 3.0) and between-state (+0.5, -2.0 to 2.9) components spanned zero. Conversely, the published cumulative CFR was 5.4 to 6.2 percentage points higher because 70 deaths were added retrospectively by week 36 outside weekly reports. Reconciling cumulative figures would require 279 missed survivors (6% of suspected cases not confirmed). Interpretation. The 2026 CFR rise came from deaths added to cumulative totals outside the weekly counts, and published data cannot attribute it to care. Endemic zoonotic CFRs cannot serve as clinical outcome measures unless testing volumes, deaths added late, and post-mortem sampling are published alongside case counts. Funding. US NSF-NIH-NIFA EEID; UK BBSRC; Birgitta Sintring Fellowship (Uppsala University).

The Democratic Republic of the Congo is experiencing a major outbreak of Ebola disease caused by Orthoebolavirus bundibugyoense (Bundibugyo virus), which was declared on May 15, 2026. To investigate the timing of emergence and early transmission, we generated near full length Bundibugyo virus genomes from 686 PCR-confirmed individuals across 22 health zones. We estimated the time of emergence as late February 2026 (95% highest posterior density interval [HPDI]: January 21 and March 25, 2026) and an evolutionary rate of 8.7X10-4 substitutions per site per year (95% HPDI: 7.6 and 9.9X10-4), with no evidence of mutations associated with rapidly growing lineages.

The 2026 multinational Andes virus (ANDV) outbreak linked to cruise-ship travel from Argentina triggered extensive contact tracing and quarantine. Whether intervention on this scale was necessary or sufficient depends on the risk of onward transmission, which can be difficult to estimate early in an outbreak. Using transmission-pair data from the 2018--2019 outbreak in Epuyen, Argentina, and a mechanistic model linking viral growth, symptom onset, and transmission, we estimated that 42.4% (95% CrI: 18.2-69.7\%) of transmission occurs before symptom onset and that the median incubation period is 18.5 days (95% CrI: 16.5-19.5). We simulated outbreaks under an Epuyen-calibrated estimate (R = 2.12, k = 0.316) and a pooled estimate from 15 prior ANDV investigations (R = 0.24, k = 0.39), with intervention beginning after two generations, as in the cruise-associated event. Under the higher-transmission scenario, missing 10% of exposed individuals or downstream contacts resulted in a 29.9% probability of continued spread and a 20.6% probability that at least 5,000 ultimately uninfected people would be quarantined. Under lower transmission, continued spread stayed below 8%. However, the risk of onward transmission could not be estimated precisely from the first several detected cases. These findings therefore support rapid, comprehensive contact tracing and quarantine after large international exposure events despite substantial costs.

Japanese encephalitis virus (JEV) is a leading cause of viral encephalitis in humans in Asia. Prior to 2021, only sporadic outbreaks had been detected in Australia's tropical northern extremes. However, during 2021-23, JEV infection was identified in 45 people and in more than 85 piggeries, together with many detections in feral pigs, mosquitoes, and other livestock across Australia, including in the temperate far south. Here we estimated the spatial extent of virus transmission during the outbreak (the realised niche) and the area environmentally suitable for transmission (the potential niche). We collated a national dataset of JEV surveillance and detection in humans, mosquitoes, domestic pigs, feral pigs, and sentinel chickens from 2021-23. We combined these data with (1) previously published predictions of habitat suitability for vertebrate host and vector species, and (2) estimated densities of humans, domestic pigs, and feral pigs, in a multipart assessment of spatial risk. Our model projected broad potential environmental suitability over much of northern and eastern Australia during the outbreak period, but floodplain wetland areas in the north and the inland east of Australia had both the highest estimated environmental suitability for transmission, and the strongest evidence for virus circulation.

Recent zoonotic coronavirus outbreaks have sparked an interest in understanding coronaviruses circulating in animal reservoirs. While bats are recognised as major reservoirs for these viruses, coronaviruses have also been detected in a wide range of terrestrial small mammals, particularly rodents. However, coronavirus diversity in these mammals, specifically in Europe, is still poorly characterised. In this study, we detected and characterised coronaviruses in terrestrial small mammals and bats from Belgium, France, Germany, and Ireland. We screened tissue samples from rodents and shrews and environmental bat guano using pan-coronavirus real-time and conventional PCRs, with positive results confirmed by sanger sequencing. Among 2667 bat and 1152 terrestrial mammal samples, we detected 59 positive samples, 36 from bats and 23 from rodents, from which we recovered 60 coronavirus sequences, spanning both Alphacoronavirus and Betacoronavirus lineages. Through next generation sequencing we identified one Pipistrellus pygmaeus bat guano sample carrying two distinct alphacoronaviruses, representing Nyctacovirus and Pedacovirus subgenera. Among rodents, most coronavirus-positive samples originated from a zoo in Belgium, where several CoV lineages co-circulated. The identified rodent coronaviruses clustered among previously described rodent-associated lineages, some of which also include human and other mammal-derived coronavirus sequences. Consistent with previous studies, we found sarbecoviruses in horseshoe bats (particularly Rhinolophus ferrumequinum and R. hipposideros) and merbecoviruses in Plecotus auritus bats, and these viruses are distantly related to the human coronaviruses of the respective families. Similar to bat coronaviruses, some rodent coronaviruses strains seemed to be association with specific rodent species. In conclusion, our study enhances the understanding of coronaviruses in rodents and bats, revealing potential hotspots for these viruses and their implication for human and animal health. These findings underscore the necessity for continued surveillance of coronaviruses in wildlife reservoirs to mitigate future zoonotic spillover risks.

Enteric pathogens account for a substantial global disease burden, yet population-based surveillance remains limited by the transient nature of pathogen shedding, which constrains the sensitivity of stool-based molecular testing to a narrow detection window. Detection of IgG responses in serological surveys could enable new insights into enteric pathogen transmission, but benchmarking serological measures relative to stool-based measures of infection remains a critical evidence gap. We compared measures of disease transmission in longitudinal birth cohort samples using multiplex IgG (1,601 dried blood spots, 370 children) and PCR assays (2,231 stool samples, 370 children) that overlapped for nine pathogens (norovirus GI, GII, Shigella/enteroinvasive Escherichia coli (EIEC), Campylobacter spp., enterotoxigenic Escherichia coli (LT-ETEC), Salmonella enterica, Giardia spp., Cryptosporidium spp., Entamoeba histolytica). LT-ETEC and Campylobacter ranked highest while E. histolytica and S. enterica ranked lowest by both IgG and PCR measures of infection. Measures of infection were less aligned for norovirus GI, norovirus GII, Cryptosporidium, Shigella/EIEC, and Giardia. Despite this, for most pathogens, and across both measures, force of infection was lowest in the urban city of Esmeraldas and substantially higher in more rural populations, with relative risks in assay measures (seroconversion rate and PCR detected prevalence) over 2.0 for pathogens with the largest differences (Shigella/EIEC and norovirus GI). Together, our results suggest that although absolute levels of infection differed between assays, IgG and PCR captured consistent relative risk of infection across geographic strata, suggesting either method can identify high- versus low-transmission settings.

In England and Wales, Usutu virus (USUV) was detected in 2020 and is now established. West Nile virus (WNV) has so far only been detected in a single location, in two Aedes vexans mosquito pools sampled during 2023 surveillance. Given the growing threat to the UK from Culex-borne viruses there is a need to undertake risk assessments to contribute to preparedness and surveillance strategy for both viruses across human and animal health sectors. Here, we present the first application of a mechanistic R0-based model, incorporating temperature dependence and combining data on vector species distribution with projected future climate scenarios, to assess transmission suitability for WNV and USUV across England and Wales. Under current climate conditions, the two viruses showed comparable spatial patterns, with risk concentrated most heavily in the southeast along the Thames estuary and extending into Kent, Essex and Surrey, as well as around Cambridgeshire and adjacent counties, and across Yorkshire, Nottinghamshire and Lincolnshire. This pattern broadly corresponded with the cumulative distribution of Culex mosquito abundance established in our earlier work (Culex pipiens pipiens, Culex pipiens molestus and Culex torrentium). Both viruses were projected to show increasing transmission suitability risk over time, with substantially steeper increases under Representative Common Pathway (RCP) 8.5 then RCP 4.5. Equine WNV cases were predicted to be most likely in southeast England, in particular around Newmarket, driven by the region's dense horse population. Among the human population, London was identified as the highest-risk area, with Liverpool and Manchester also showing elevated risk levels, driven by a combination of high human and mosquito distributions. When human population distributions were age-adjusted to account for the proportion of over 60 years-olds, there was elevated risk in coastal regions, particularly in the east (Norfolk and Suffolk) and southeast (Kent) of England. The geographic distribution of positive mosquito and bird USUV cases recorded in 2023 and 2024 broadly overlapped with areas predicted to have higher USUV suitability, providing validation for the model's spatial outputs. By characterising relative spatial transmission suitability risk, this work adds to a growing understanding of where arbovirus emergence and spread are most likely across England and Wales, and can support decisions around resource allocation, targeted surveillance efforts, and public health readiness. The results also underscore the importance of incorporating climate change and vector ecology into future modelling work, given their likely influence on how arbovirus risk evolves over time.

Traditional veterinary pathology investigations on wild animals generally conclude a primary cause of death based on a combination of observed clinical signs, gross and microscopic lesions, microbial culture and PCR. However, these methods may fail to capture the broader microbial community of the host. We employed metatranscriptomic sequencing to characterise the potential pathobiome of necropsied marine turtles, comparing these findings with corresponding veterinary pathology reports. Tissue samples were collected from 76 individuals spanning three species of marine turtles -- the green turtle (Chelonia mydas), the hawksbill turtle (Eretmochelys imbricata), and the loggerhead turtle (Caretta caretta) -- across the coastline of New South Wales, Australia. Reported causes of mortality ranged from infectious disease to trauma. We identified a diverse range of parasites within the genera Neospirochis, Hapalotrema, Paraorgymatobothrium, Eimeria and Callitetrarhynchus, and bacteria including the genera Aeromonas, Clostridium, and Vibrio. Novel viruses of the families Astroviridae, Caliciviridae, Hepaciviridae, Hepeviridae, Nyamivirdae, Orthomyxoviridae, Picobirnaviridae and Rhabdoviridae were also identified. In cases where infectious disease was noted in the pathology report, we frequently observed high pathogen read counts consistent with the listed primary diagnoses. However, we also detected a range of incidental infections involving eukaryotic parasites, bacteria, and viruses. The diversity of infectious agents detected in marine turtles suggests that the observed disease outcomes are unlikely to be driven by a single causative agent, but rather by complex interactions between host health, the pathobiome, and environmental stressors. We discuss the potential implications for turtle health and conservation.

The 2026 Andes virus (ANDV) outbreak aboard the MV Hondius cruise ship resulted in 11 confirmed cases and 3 deaths and raised questions regarding the origin of infection, with much media focus resting on a landfill in Tierra del Fuego. We evaluated competing exposure hypotheses by assembling open data on reservoir host occurrences, rodent serosurveys, and historical ANDV outbreaks along with the index case's self-documented, publicly-posted citizen-science digital record of their movements. Historical outbreaks associated with human-to-human transmission were concentrated within a restricted region spanning southern Chile and adjacent western Argentina, coinciding with the distribution of the principal reservoir host, Oligoryzomys longicaudatus, and areas identified as elevated risk by multiple ecological and genetic models. The index case was documented within this transmission focus shortly before the putative exposure period. Together, our open data approach was able to rapidly locate initial exposure within the established ANDV transmission focus and develop scenarios to prioritise further epidemiological investigation.

Antimicrobial resistance is a global One Health threat connecting antimicrobial use in human health, animal husbandry, and companion animal health with concern for persistence in environmental reservoirs. Complicating this threat is the gap that exists in our understanding of the intersection of antimicrobial resistance among humans and our companion and food production animals. This study applies a visual and statistical approach to further understand antimicrobial resistance characteristics and relatedness of Escherichia coli found in humans, dogs and cattle. The primary study collection included third-generation cephem resistant (3GCR) E. coli isolates recovered from human, dog, and cattle gastrointestinal specimens and secondarily human and dog isolates recovered from infection sources, primarily urinary tract infections. We previously reported on the transferable gene targets encoding for 3GCR in colonizing isolates and here further identified the familial-like clonal group of each resistant isolate using a novel clonotype diagnostic (septatyping). Together, this approach identified distinct genetic signatures among these 3GCR isolates, many of which are peculiar to their respective host species. We found that the overlap measured by the correlation in abundance of shared clonotypes of resistant E. coli among hosts revealed statistically greater similarity between dogs and humans than between cattle and humans. Yet, the reservoir of AMR genes was highest in cattle and secondarily dogs. While these findings demonstrate that clonotypes of 3GCR E. coli in humans, dogs and cattle display significant host specificity, transient colonization from a host enriched with resistant strains may still pose considerable risk of horizontal transfer of resistance genes between hosts living in proximity to each other.