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Soil may influence pathogen persistence and outbreak dynamics, yet its characteristics and potential association with historical plague occurrence remain poorly understood. This study aimed to characterize the surface soil properties of three commensal rodent plague foci in Yunnan Province, China, and to explore their site-specific association with historical plague village status. From July to August 2019, 230&#x202f;soil samples were collected from paired historical plague (n&#x202f;=&#x202f;108) and non-plague (n&#x202f;=&#x202f;122) villages in Mile, Mangshi, and Lianghe counties. Soil pH, soil electrical conductivity (SEC), soil organic matter (SOM), and seven metal elements (Fe, Ca, Ti, Co, Cu, Ni, V) were analyzed. Non-parametric tests, Spearman correlation, principal component analysis (PCA), and binary logistic regression were employed for data analysis. The soils were overall acidic (median pH 5.82), slightly salinized (median SEC 166.51&#x202f;&#x3bc;S/cm), with moderate SOM (median 21.14&#x202f;g/kg). Concentrations of Fe, Ti, Co, Cu, Ni, and V significantly exceeded national background values (all p&#x202f;<&#x202f;0.001). Pronounced regional differences (p&#x202f;<&#x202f;0.001) were observed across the three sites: in Mile, soils were near-neutral (median pH 6.79), with the highest SEC (207.5&#x202f;&#x3bc;S/cm) and the highest concentrations of Fe (91741.03&#x202f;mg/kg), Cu (79.94&#x202f;mg/kg), and V (310.1&#x202f;mg/kg), but the lowest SOM (20.5&#x202f;g/kg); in Mangshi, soils were acidic (median pH 5.57), with intermediate SEC (165.9&#x202f;&#x3bc;S/cm) and metal levels, and moderate SOM (21.41&#x202f;g/kg); in Lianghe (n&#x202f;=&#x202f;71): Soils were the most acidic (median pH 5.48), with the lowest SEC (147.1&#x202f;&#x3bc;S/cm) and lowest metal concentrations, but the highest SOM (22.05&#x202f;g/kg). Post-hoc comparisons confirmed that Mile had significantly higher pH, SEC, Fe, Ti, Co, Cu, Ni, and V than both Mangshi and Lianghe (Bonferroni-corrected p&#x202f;<&#x202f;0.017), while no significant differences in SOM were found across regions (p&#x202f;=&#x202f;0.634). At the provincial level, historical plague villages had significantly lower Ni and V than non-plague villages (both p&#x202f;<&#x202f;0.05), though regional sub-analyses showed that this pattern was not consistent across all foci, highlighting context-dependent variations. Multivariate analysis extracted four principal components (cumulative variance: 83.72%). Multivariate logistic regression suggested that the heavy metal-rich principal component (PC1) was independently associated with reduced likelihood of historical plague village classification, while loam texture was associated with lower odds of historical plague occurrence relative to sandy soil. Soils in the three plague foci are acidic, slightly saline, and enriched in several metals, with properties varying significantly by region. In this exploratory, cross-sectional analysis, a multivariate soil profile dominated by heavy metals and loam texture showed a statistical association with historical plague occurrence. These site-specific findings provide crucial baseline data and a multivariate analytical framework for future investigations into the complex, and likely context-dependent, relationships between soil environments and plague ecology.

Plague, caused by Yersinia pestis, is a class A infectious disease in China. In order to address the practical requirements of plague prevention and control, this study conducted a systematic analysis based on the national surveillance data from 2010 to 2024. Data on human and animal plague epidemics were collected from the National Plague Prevention and Control Management Information System and analyzed using descriptive epidemiological methods. As of 2024, 12 types of natural plague foci have been identified in China. Between 2010 and 2024, 33 human plague cases and 14 deaths were reported nationwide. Geographically, cases were concentrated in Inner Mongolia (15, 45.5%), Xizang (8, 24.2%), and Gansu (6, 18.2%). By focus type, cases originated primarily from Marmota himalayana (16, 48.5%), Meriones unguiculatus (15, 45.5%), and Rattus flavipectus (2, 6.1%). Pneumonic plague was most common (15, 45.5%), followed by bubonic (10, 30.3%), septicemic (7, 21.2%), and intestinal plague (1, 3.0%). Animal plague epidemics persisted nationwide, with active outbreaks in foci of M. himalayana, Marmota baibacina, Spermophilus undulatus, and Meriones unguiculatus. Bacterial isolation positivity rates in animals and insects were 0.05%-0.13% and 0.04%-0.11%, respectively, while Indirect Hemagglutination Assay (IHA) and Reverse Indirect Hemagglutination Assay (RIHA) positivity rates were 0.08%-0.25% and 0.09%-2.18%, respectively. Currently, Polymerase Chain Reaction (PCR) testing has been implemented in some regions, with positivity rates of 0.80% in animals and 1.59% in insects in 2024. The current plague epidemic situation in China is characterized by "sporadic human cases, active animal epidemics in some foci." It is recommended to strengthen targeted surveillance, promote PCR-based screening, and enhance cross-provincial coordination.

Plague, as a highly infectious and fatal zoonotic disease, has shown a resurgence in multiple regions worldwide in recent years. Qinghai Province, a significant natural plague focus of the plateau type in China, has experienced periodic outbreaks. However, existing research has primarily focused on the spatial prediction of marmot-suitable habitats, with relatively few studies targeting the spatial prediction of animal plague risk zones. Data on animal plague occurrence sites in Qinghai Province from 1956 to 2022 were collected. Terrain features, bioclimatic variables, land use types, and human disturbance variables related to plague spatial distribution were extracted. A maximum entropy (MaxEnt) model was used to construct a spatial prediction model for animal plague risk zones, and The model's performance was evaluated using the average Area Under the Curve (AUC) and True Skill Statistic (TSS) values on the testing datasets. Based on the model results, the animal plague risk zones were delineated, and the area size and population residing within predicted risk zones were calculated. The Maxent model achieved average AUC and TSS values of 0.827 and 0.5, respectively, on the testing datasets. The predicted animal plague risk zones in Qinghai Province covers 234,000 km2 (approximately 32.4% of the total area of Qinghai), with a population of 3.902 million residing within predicted risk zones (65.8% of the province's total population). This study utilized the MaxEnt model combined with GIS spatial analysis technology to predict the spatial distribution of animal plague risk zones in Qinghai Province and estimate the area size and population residing within predicted risk zones. The findings can provide a scientific basis and decision-making support for targeted plague prevention and control in Qinghai.

Population outbreaks of house mice (Mus musculus L.) (= mouse plague) are a periodic feature of southeastern Australia's grain belt, causing significant crop damage and social-economic impacts. From 1904 to 1980, a plague occurred once every 5-7 years. Since 1980, there has been an increasing frequency observed in all regions except South Australia. Numerous hypotheses have been proposed to describe the phenomenon, but the specific combination of rainfall patterns in generating conditions for a mouse plague is not clear. Monthly rainfall data over 125 years were collected from three locations, and a measure of 6-monthly rainfall anomaly was calculated to determine trends in dry (deficit) and wet (surplus) periods. These rainfall patterns were then analyzed in relation to the timing of known mouse plague events. A mouse plague that occurred after a particular sequence of dry weather was observed (well below 6-month accumulated long-term average rainfall anomaly of -45 to 65&#xa0;mm over 25-31 months), followed by an exceptional wet period (well above long-term 6-month accumulated average of 55 to 90&#xa0;mm over 17-20 months). The combination of the magnitude and duration of rainfall deficit, followed by the magnitude and duration of the rainfall surplus, was required; anything less did not lead to a plague. The dry conditions appear to reset the system in some way, with mice responding to increased food supply following exceptional post-drought rainfall. A conceptual model of factors driving mouse plagues is proposed. There remain questions about the underlying biological mechanisms that drive these plagues, including density-dependent effects and the role of post-traumatic stress through inherited traits.

Plague is among the most devastating diseases in human history1. However, early strains of the plague-causing bacterium Yersinia pestis lacked virulence factors that are required for the bubonic form until around 3,800 years ago2,3. Consequently, the morbidity and mortality of early plague strains remain unclear. Here we describe early plague strains that are associated with two phases of outbreaks among mid-Holocene hunter-gatherers near Lake Baikal in southeast Siberia, beginning from about 5,500 years ago. These outbreaks occur across four hunter-gatherer cemeteries, with a 39% detection rate for plague infection. By reconstructing kinship pedigrees, we show that small familial groups were affected, consistent with human-to-human spread of disease, and that the first outbreak occurred within a single generation. The infections appear to have resulted in acute mortality, especially among children (aged 8 to 11 years). We further note functional differences, including in the ypm superantigen locus, which is also present in present day Yersinia pseudotuberculosis. The new strains diverge ancestrally to known Y. pestis and constrain the timing of its emergence, indicating that this happened before approximately 5,700 years ago. These findings show that plague outbreaks happened earlier than previously thought and were indeed lethal. We contend that the occurrence of outbreaks among mid-Holocene hunter-gatherer communities well outside the sphere of Late Neolithic Europe challenges the notion that higher population densities and lifestyle changes during the Neolithic agricultural transition were prerequisites for plague epidemics.

Plague is a disease that poses serious threats to public and ecosystem health. Its causative bacterium, Yersinia pestis, was transported to North America around 1900, where it quickly became established in native rodent populations and spread throughout the western half of the United States by the mid-1900s. Many questions remain about plague circulation in the numerous rodent species involved, but its ecology in rabbits and other lagomorphs is even less understood. We describe a plague epizootic that appeared to involve both desert cottontail rabbits (Sylvilagus audubonii) and black-tailed jackrabbits (Lepus californicus). We believe this to be the first such description to involve both species of rabbits and the first description of a plague epizootic in the Mojave Desert. This epizootic also involved a human case of plague; we discuss human health ramifications of plague in rabbits and suggest a potential link between plague and the general long-term decline in rabbit populations, especially for jackrabbits.

Plague is a zoonotic disease of mammals caused by the bacterium Yersinia pestis. Because plague is primarily transmitted by fleas (Siphonaptera), rates of plague transmission are expected to increase with flea abundance. Edaphic factors can influence the abundance and dispersion of fleas, suggesting that soils may play important roles in plague ecology. From June to August 2010-12, in northern New Mexico, USA, we investigated the effects of soil texture, soil moisture, and soil water-holding capacity on the abundance of adult fleas parasitizing colonial, burrowing black-tailed prairie dogs (Cynomys ludovicianus, BTPDs). We sampled BTPDs 1,741 times on 20 sampling plots distributed among 13 BTPD colonies, detecting 9,541 adult fleas on BTPDs. Fleas were most abundant on BTPDs in areas with coarse surface soils, and in areas with moderately textured subsurface soils at the average depth of BTPD nest chambers. Coarse surface soils may facilitate water percolation to BTPD nests, where the moisture could generate humid microclimates that benefit desiccation-prone fleas. Moderately textured subsurface soils, of intermediate water-holding capacity, can store water, which may increase burrow humidity. Moreover, moderately textured subsurface soils in BTPD nests may increase survival of flea larvae and pupae, facilitating their development to adulthood. That said, excessive moisture and sodden soils can favor fungi and mites, some of which are lethal to fleas. In our study, fleas were most abundant in areas with subsurface soils of intermediate moisture content. Our findings complement an accumulating number of studies, indicating that edaphic factors play important roles in flea and plague ecology.

The COVID-19 pandemic led to unprecedented interest and participation in vaccine trials globally, and a concurrent increase in vaccine hesitancy. Whether this impacted recruitment of healthy volunteers to subsequent non-COVID vaccine trials is not well studied. We explored the impact of the COVID-19 pandemic on motivations for participating in two clinical trials of the same novel anti-plague vaccine, conducted in the United Kingdom (UK) and Uganda in 2021 and 2022. Participants enrolled in PlaVac (UK) and PlaVac Uganda, Phase I trials of ChAdOx1 Plague vaccine, were invited to complete an optional questionnaire and semi-structured interview examining motivations for participating, including questions on the impact of the COVID-19 pandemic on their decision. Questionnaires were self-administered and interviewer-administered for UK and Uganda studies, respectively. Interviews were conducted in local languages, transcribed in English, and analysed using thematic analysis. Results were compared between studies. Thirty-one of the 45 (68.9%; 25.8% female) UK trial participants and all 36 (100.0%; 27.8% female) of the Uganda trial participants completed questionnaires responses, and 19 Uganda questionnaire respondents completed interviews. Responses to questions on the impact of the COVID-19 pandemic on volunteering decisions were divergent between countries, with little effect for UK participants but a strong positive effect for Ugandan participants. Themes relating to this effect were "contributor, not cause" in the UK, and in Uganda were preparedness (wanting to contribute to vaccine development to prevent suffering and death from future epidemics), increased awareness (understanding the vaccine development process and seeing rapidly deployed COVID-19 vaccine trials gave them confidence), and personal protection (believing themselves to be protected by the novel plague vaccine). Participants in both studies expressed trust and confidence in the study vaccine which shares the same adenoviral-vectored platform technology used to elicit an immune response (ChAdOx1) with the COVID-19 vaccine ChAdOx1 nCoV-19 (Vaxzevria, AstraZeneca). For Ugandan participants, COVID-19 and mass vaccination increased knowledge about vaccines and trials and encouraged them to participate in research, but had little impact on UK volunteers. There was no evidence of a negative effect of perceptions of the related ChAdOx1 nCoV-19 vaccine on trial participants' confidence in the novel plague vaccine's safety. Current controlled trial: ISRCTN41077863, prospective registration date: 19/03/2021, and current controlled trial: ISRCTN79243381, prospective registration date 05/08/2022.

Epidemics have historically been both biomedical disasters and cultural stories that societies interpret and recount. This study explores the epidemic imaginary, examining how literature and cinema symbolically depict contagion by analysing narratives of contagion produced during the Plague era in literature and modern pandemic representations in film. The research considers some plague-era literature, such as Albert Camus' The Plague (1947) and Thomas Mann's Death in Venice (1912), alongside more recent pandemic literature like Dean Koontz's The Eyes of Darkness (1981), as well as two films: Contagion (2011), directed by Steven Soderbergh, and Outbreak (1995), directed by Wolfgang Petersen. Drawing from interdisciplinary fields including literary studies, film theory and medical humanities, the study highlights moments of systemic and existential responses to contagion. It explores recurring themes such as fear, denial, governance, death, mortality and resilience, demonstrating how epidemics serve as meaningful moments for both existential reflection and systemic analysis. I argue that epidemic stories function as cultural scripts, that literature subtly allegorises contagion through introspection, and that cinema vividly dramatises urgency by depicting collapsing systems. Overall, these works highlight how societies narrate and remember solidarity during crises, rearticulating collective resilience in the face of devastation.

Plague is a zoonotic disease of mammalian hosts and flea vectors. Wildlife biologists most commonly mitigate plague by controlling flea populations. We evaluated the efficacy of edible baits for systemic flea control with two cricetid species on colonies of black-tailed prairie dogs (Cynomys ludovicianus): the western deer mouse (Peromyscus sonoriensis) and the northern grasshopper mouse (Onychomys leucogaster). We tested grain bait with 0.005% fipronil by weight and "FipBit" pellets with 0.46-1.52 mg of fipronil/pellet. Flea prevalence was assessed via combing of live-trapped mice. In one experiment with fipronil grain bait and FipBits (n=564 combings), flea prevalence declined from 74% (grain) and 45% (FipBits) before treatments to 0% for both treatments from 30 to 44 d and from 324 to 413 d after treatments. During a second experiment with FipBits (n=299 combings), flea prevalence declined from 13% to 32% before treatments to 0% from 11 to 15 d after treatments, but increased to 29-56% from 349 to 378 d after treatments. Results herein suggest annual fipronil bait treatments may be most effective for flea control.

This review provides a comprehensive overview of the genetic diversity and epidemiological potential of Yersinia pestis in Kazakhstan's natural plague foci, emphasizing the link between genotypic variation and outbreak capacity. Integrating historical epidemiological records with contemporary microbiological and genomic data (including PCR, VNTR/MLVA, SNP analysis, and whole-genome sequencing), we evaluate core and accessory genome variations. The data reveal substantial regional heterogeneity. High-risk desert foci (Caspian and Aral regions) are dominated by the Medievalis biovar, including atypical genovariants lacking canonical markers. Conversely, high-mountain foci (Sarydzhaz, Talas) harbor the Antiqua and Talas biovars, primarily linked to enzootic circulation. Notably, the Ili River focus exhibits extreme genomic variability, featuring strains with plesiomorphic traits. Furthermore, the widespread distribution of mobile elements like the cryptic plasmid pCKF suggests significant horizontal transfer contributing to pathogen adaptation. Ultimately, Central Asian plague dynamics are driven by complex evolutionary and ecological interactions. Given climate change and expanding human-wildlife interfaces, continuous genomic and ecological surveillance is essential for the early detection of high-risk Y. pestis genovariants and improving public health preparedness.

Duck plague virus (DPV) is a highly contagious pathogen that causes severe immunosuppression and high mortality in waterfowl, resulting in substantial economic losses to the poultry industry. However, the mechanisms by which DPV evades host innate immune responses remain incompletely understood. In this study, we investigated the role of the DPV tegument protein US2 in regulating host antiviral responses. pUS2 significantly suppressed IFN-&#x3b2; promoter activation induced by poly(I:C) and poly(dA:dT) and reduced the transcription of IFN-&#x3b2; and interferon-stimulated genes (ISGs), including OASL and Mx. Further analysis showed that pUS2 specifically inhibited IFN-&#x3b2; promoter activation triggered by the RIG-I/MDA5-MAVS signaling pathway. Co-immunoprecipitation and immunofluorescence assays demonstrated that pUS2 directly interacted with RIG-I in the cytoplasm and reduced its protein abundance in a dose-dependent manner. Mechanistically, pUS2 enhanced K48-linked ubiquitination of RIG-I and promoted its degradation through a p62-mediated autophagy pathway. Deletion of the US2 gene moderately reduced viral replication efficiency in DEF cells and enhanced expression of type I interferons and ISGs. In vivo experiments further showed that ducks infected with the US2-deleted virus exhibited reduced pathogenicity, including lower viral loads, milder tissue damage, and increased survival rates compared with those infected with the parental virus. Collectively, these findings demonstrate that DPV US2 antagonizes host innate immunity by targeting the RIG-I signaling pathway and promoting RIG-I degradation through autophagy. This study provides new insights into the immune evasion strategies of DPV and advances our understanding of DPV-host interactions.

Plague, caused by Yersinia pestis, persists as a public health threat, particularly in natural foci such as China's Inner Mongolia Autonomous Region. Understanding the distinct environmental drivers of pathogen transmission from wildlife reservoirs to humans is critical for targeted control. We integrated long-term human case data (1950-2023) with extensive rodent serological surveillance (2005-2023) to model these dynamics. Using a Generalized Additive Model and interpretable machine learning, we found that human cases were concentrated in specific foci and nonlinearly linked to proximity to railways and precipitation, but not rivers. In contrast, enzootic maintenance was predominantly driven by a negative correlation with nighttime light, nonlinear climatic effects, and positive associations with specific land uses (water, forest, residential). Our framework reveals that spillover and enzootic cycles are governed by differing environmental factors. This approach enables spatially refined risk assessment, guiding surveillance to incorporate the distinct anthropogenic and climatic drivers of plague transmission.

The Australian Plague Locust (APL), Chortoicetes terminifera, the most important pest locust in Australia, can cause significant damage to crops and grasslands when present in high numbers. We have developed a new LAMP (loop-mediated isothermal amplification) assay specifically targeting APL for rapid diagnostics to support locust management. We tested five DNA extraction methods for potential near-field use and designed an APL gBlock as a synthetic positive control. The performance of new LAMP assay was assessed against a panel of eleven closely related Australian grasshopper species (family Acrididae). The optimised LAMP assay produced amplification only from APL DNA, on average in 18.0&#x2009;&#xb1;&#x2009;2.9&#xa0;min, with an anneal derivative of 79.9&#x2009;&#xb1;&#x2009;0.5&#xa0;&#xb0;C, and gBlock produced a different anneal derivative of 83.5&#x2009;&#xb1;&#x2009;0.5&#xa0;&#xb0;C. The LAMP assay was sensitive to very low levels of DNA, with detection down to 0.2 picogram of APL DNA. The speed of application and accurate identification results generated, enables this scalable assay to be easily used in the field as a new tool for APL control, providing positive/negative results within an hour. This capability will prove an essential aid during sporadic APL population growth events, when accurate species-level identification of substantial numbers of nymphs, prior to adult locusts swarming, is a critical aspect of pest management.

By drawing parallels rather than following events exactly, we interpret Daniel Defoe's most important work as a literary response to the Bills of Mortality that foreshadows enduring concerns of epidemic surveillance. These include the aggregation of deaths in time and space, the interpretation of trends, and a persistent awareness of bias and uncertainty. We examine how Defoe's narrator "Henry Foe (H.F.)" reads, quotes, compares, and questions the weekly bills in the context of the Great Plague of London in 1665. He treats numerical data neither as transparent reality nor as mere ornament, but as contested evidence shaped by under-registration, diagnostic ambiguity, and pressure to minimize public alarm. Through close reading of selected passages, we show how H.F. juxtaposes printed figures with street-level observation, theological and humoral explanations, and contemporary debates on miasma, contagion, and quarantine. We do not claim that Defoe practiced surveillance in any modern sense. Rather, we argue that his narrative illuminates recurrent ethical and epistemological questions about data quality, transparency, trust, and the communication of risk. These questions have become newly salient amid recent preoccupations with dashboards, case counts, and excess mortality during the COVID-19 pandemic. Defoe's journal thus offers historians of medicine and public health a sophisticated early case study of the promises and pitfalls of mortality statistics.

We evaluated the effects of fipronil bait pellets on two cricetids that commonly occupy colonies of black-tailed prairie dogs (Cynomys ludovicianus; BTPDs): western deer mice (Peromyscus sonoriensis) and northern grasshopper mice (Onychomys leucogaster). In one experiment, bait pellets (0.96&#x202f;mg fipronil/bait) were applied at 75 baits/ha to three 1.44-ha plots on a BTPD colony. Mouse abundance declined by 70% from before to 6-10&#x202f;d after treatment. In a second experiment, bait pellets (0.46 or 1.52&#x202f;mg fipronil/bait) were applied at 125 baits/ha to four plots (0.85-1.86&#x202f;ha) on two BTPD colonies; two non-treated plots were baselines (1.09 and 2.06&#x202f;ha). From before to 11-15&#x202f;d after treatment, mouse abundance declined by 51%- 67% on the treated plots vs. a decline of 9% on the non-treated plots. Mouse survival from before to 11-15&#x202f;d after treatment was 51% lower on the treated plots. In a third experiment, bait pellets (0.84&#x202f;mg fipronil/bait) were applied at 125 baits/acre on two 1.44-ha plots on a BTPD colony; two 1.44-ha non-treated plots were baselines. Mouse survival from before to 30-44&#x202f;d after treatment was 45% lower on the treated plots; the abundance of deer mice on the treated plots remained similar from before to 30-44&#x202f;d after treatment, perhaps due to juvenile recruitment and/or immigration. In a laboratory experiment, 33 deer mice offered one bait pellet (0.86&#x202f;mg fipronil/bait) consumed 27% of their bait, on average (range&#x202f;=&#x202f;0-100%). Over 3&#x202f;d, deer mouse mortality was estimated at 53%; mortality increased with fipronil dose, which averaged 11&#x202f;mg fipronil/kg body mass (range&#x202f;=&#x202f;3-46&#x202f;mg/kg). Brain samples were available from 31 deer mice; all tested positive for fipronil sulfone, the primary mammalian metabolite of fipronil, at 19 to 61,205&#x202f;ng fipronil sulfone/g. Additional experiments could determine if these findings scale up to larger landscapes.

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