Vector borne and zoonotic diseases最新文献

Introduction: This study explores the application of long-read sequencing technologies for genotyping, epigenetic profiling, and epidemiological monitoring of Yersinia pestis isolates obtained from natural foci in Central Asia and previous zoonotic outbreaks.

Methods: Computational tools for genome assembly and genotyping were developed, enabling high-precision identification of both chromosomal and plasmid sequences, including the small plasmid pCKF.

Results: Genotyping based on genetic polymorphisms distinguished the major Y. pestis biovars and lineages, and revealed cluster-specific diversity among Medievalis (2.MED) isolates, including groups of strains associated with different plague foci and disease outbreaks in domestic animals and humans. These specific genomic polymorphisms identified in subclades of 2.MED isolates allow their high-precision identification. The distribution of pCKF-positive strains in the region and the potential involvement of these pathogens in disease outbreaks are discussed. Additionally, comparative epigenomic analysis uncovered strain-specific cytosine methylation patterns at cgGATCG motifs. Further studies involving more sequenced strains are needed to determine whether this cytosine methylation specificity is linked to genome function regulation and adaptation to different hosts and environments.

Conclusions: These findings demonstrate the effectiveness of long-read sequencing technologies in revealing both genetic and epigenetic features of bacterial pathogens, contributing to our understanding of the evolutionary mechanisms underlying the emergence and spread of this especially dangerous infection.

Introduction: Cutaneous leishmaniasis (CL) is a parasitic infection that presents a significant public health concern in the Qassim region of Saudi Arabia. This retrospective observational study aimed to investigate the seasonal patterns and distribution of CL cases in the Al-Qassim region, highlighting the importance of these factors in understanding the disease trends.

Methods: The present study utilized retrospective observational data from a population cohort to examine reported instances of CL over an 8-year period. The Ministry of Health monitored the CL cases from January 2016 to December 2023. The data were systematically arranged by year, gender, age group, nationality, and season to analyze trends and variations in the disease's distribution at the population level. The chi-square test and analysis of variance were used to analyze the data.

Results: A total of 1199 confirmed CL cases were reported during the study period, with significant year-to-year variation (p < 0.005). Males accounted for the majority of cases (72.8%), and the highest burden was observed among individuals aged 15-45 years. Saudi nationals represented most reported cases (76.8%). A consistent seasonal pattern was observed, with higher case numbers during spring and winter, while summer showed the lowest incidence.

Conclusion: CL in Al-Qassim displays distinct demographic and seasonal trends, particularly among young adult males and during the spring and winter months. These patterns highlight the importance of targeted preventive measures and health interventions in high-risk populations and peak transmission periods.

Background: Leishmania major and Leishmania infantum infection were evaluated in sand flies and rodents during a cutaneous leishmaniasis (CL) outbreak in two military camps in southern Israel (2022-2023). The efficacy of a novel intervention combining drone-based pesticide application and rodent bait stations was assessed.

Methods: Sand flies and rodents were sampled and tested for Leishmania by PCR and DNA sequencing. In April 2023, precision spreading of pesticides via drones and bait stations targeting Meriones tristrami and Mus musculus domesticus was done in camp 2, while camp 1 served as control. Leishmania infection rates in vectors and reservoirs were compared before and after intervention, alongside CL incidence in soldiers.

Results: A total of 7,204 female Phlebotomus papatasi were analyzed. The minimal infection rate of L. major in camp 2 declined from 1.23 in 2022 to 0.03 post-iinterventionin 2023 (p = 0.034). In camp 1, no significant change occurred (0.50 in 2022 vs. 0.22 in 2023, p = 0.622). Among 63 rodents, 8 (12.7%) were infected: five with L. infantum (2/11 M. musculus domesticus [18.2%] and 3/52 M. tristrami [6%]) and three M. tristrami (6%) with L. major. Overall rodent infection declined significantly from 24.1% in 2022 to 2.9% in 2023 (p = 0.032), with camp 2 showing the most pronounced reduction (31.6% vs. 3.3%, p = 0.02). Human CL incidence also dropped significantly: in camp 1, from 17.1 to 2.6/1000, and in camp 2, from 33.3 to 4.9/1000 (p < 0.001).

Conclusions: Significant reductions in Leishmania infection were observed in vectors, reservoirs, and humans following the intervention. Although CL dynamics are influenced by multiple factors, these findings support the potential of drone-based and host-targeted approaches for integrated leishmaniasis control. Further studies are required to validate and optimize such technologies.

Background: In Mexico, two Mammarenavirus genotypes have been identified: Real de Catorce virus and Ocozocoautla de Espinosa virus (OCEV), which are found in rodents (Neotoma leucodon and Peromyscus mexicanus). Mammarenaviruses from clade B cause mild to severe infectious diseases in humans, particularly in South America. A 1967 outbreak in Chiapas, Mexico, was potentially linked to the OCEV.

Materials and methods: Between 2017 and 2020, we collected bats across southern/southeastern Mexico to identify Mammarenavirus reservoirs. We analyzed 81 liver samples from 14 bat species using nested PCR. For quality control, we synthesized and OCEV S-region fragment into an ampicillin-resistant pUC57 plasmid, cloned in One Shot Stbl3 chemically competent E. coli.

Results: Here, we report the first detection of a Mammarenavirus (OCEV) in an Artibeus lituratus bat from Sabancuy, Campeche, southeastern Mexico. This finding represents the third Mammarenavirus recorded in this bat species in the Americas, suggesting it may harbor multiple Mammarenavirus species (OCEV and Mammarenavirus tacaribeense).

Conclusions: While this represents the first documentation of OCEV in a bat, it remains unknown whether environmental stressors could facilitate potential transmission to humans, particularly given the close association between Artibeus bats and human populations.

Background: Dengue fever remains a major global public health challenge, particularly in endemic regions, due to its complex clinical presentation, diagnostic limitations, evolving epidemiology, and immunopathogenic mechanisms such as antibody-dependent enhancement (ADE). Despite advancements, integration among clinical care, diagnostics, transfusion practices, vector control, and public health systems remains limited.

Objective: This review aimed to synthesize current evidence on dengue management by integrating clinical, diagnostic, transfusion, and public health domains, highlighting persistent gaps and proposing coordinated, multidisciplinary response strategies.

Methods: A narrative review was conducted using peer-reviewed English-language literature published between 2018 and 2025. Databases searched included PubMed, Scopus, Web of Science, and Google Scholar. Search terms included "dengue diagnosis," "transfusion management," "vector control," and "public health intervention." A total of 30 studies were selected based on relevance to diagnostic practices, transfusion strategies, vector control, and systemic health responses. Thematic synthesis and quality assessment were applied.

Results: Findings confirm that ADE contributes to increased viral replication and severity, highlighting the need for individualized fluid management and evidence-based transfusion protocols. Rapid diagnostic tests and biomarkers such as C-reactive protein and IPF% facilitate early detection of severe dengue but are underutilized. Platelet transfusions are inconsistently applied, often without standardized clinical criteria. Integrated vector control strategies, including Wolbachia-infected mosquitoes, and community engagement approaches demonstrate effectiveness, although postpandemic disruptions and poor interagency coordination limit their impact. Cost-effectiveness studies support combined vaccination and vector interventions for optimal disease reduction.

Conclusion: This review emphasizes the necessity of a unified, systems-based approach to dengue management. By integrating clinical staging, diagnostics, transfusion protocols, vector control, and public health frameworks, dengue outbreak responses can be substantially strengthened. Multidisciplinary coordination, behavior-informed health strategies, and sustained public health engagement are essential to improving preparedness and reducing the global burden of dengue.

Background: Q fever, caused by Coxiella burnetii, is an underdiagnosed zoonotic disease with significant public health implications. Serological tests remain the diagnostic cornerstone but often fail in early infection. This study investigates the utility of polymerase chain reaction (PCR) targeting the IS1111 gene for molecular detection of C. burnetii in human clinical samples from a resource-limited setting.

Methods: A retrospective PCR-based study was conducted on 243 archived clinical specimens collected from febrile patients across 11 districts of North India. DNA was extracted and subjected to conventional PCR targeting the IS1111 insertion sequence. Samples positive for C. burnetii were further evaluated for coinfection with rickettsial pathogens using real-time and nested PCRs. Sequencing and phylogenetic analysis were performed on positive samples to determine genetic relationships.

Results: C. burnetii DNA was detected in 4 of 243 samples (1.64%). Half the positive cases belonged to the patients in 1-15 year age group, and two had coinfections with Orientia tsutsugamushi. One case showed coinfection with spotted fever group rickettsia. Clinical features included fever (100%), myalgia (75%), and rash (25%). Phylogenetic analysis revealed that the isolates clustered with the Z3055 reference strain, indicating a close genetic relationship to known zoonotic strains.

Conclusion: PCR targeting IS1111 is a valuable diagnostic tool for early detection of C. burnetii, particularly in settings where serological testing is delayed or unavailable. Detection in pediatric patients and coinfection with other rickettsiae underscore the need for broader diagnostic consideration of Q fever in endemic febrile illnesses.

Background: Throughout Armenia, a range of climate conditions exist, from dry subtropical to cold alpine, with a topographic diversity from 400 to 4,100 meters above sea level. Climate analysis has suggested what the territory of Armenia may experience in response to climate change. The persistence of tularemia in Armenia, in conjunction with observed ecological trends, indicates that host reservoir distributions are likely to shift, consequently altering the geographic regions at risk of transmission. This study endeavors to evaluate the potential effects of climate change on the habitat suitability and population dynamics of the common vole, the principal reservoir of Francisella tularensis in Armenia. The objectives aim to elucidate prospective changes in disease-endemic areas, thereby informing targeted control strategies to mitigate pathogen dissemination and reduce public health risks associated with tularemia.

Methods: Field and laboratory data from 2000 to 2023 on the common vole and presence of tularemia were compiled from the National Center for Disease Control and Prevention archived records. For spatial and geostatistical analyses, data were compiled from monthly historical temperature and precipitation records from 2000 to 2021 and forecasted data from the WorldClim database. Data were analyzed using a geographic information system.

Results: The comparison of current climate data with predictive models indicates a likely shift in regions with favorable habitats for the common vole. By 2100, areas below 2,000 meters are projected to partially lose suitability, the conditions there could be less suitable for particular animal species. Currently, the common vole's habitat area is above an altitude of 1,400 meters above sea level but by 2100, changes in climate suggest the habitat will shift above an altitude of 2,000 meters above sea level.

Conclusion: The vole distribution shrinks because of the change in habitats attributed to climate change. This dynamic underscores the critical need for more targeted surveillance and integrated collaboration between human and animal health agencies to effectively monitor alterations in the ecology of zoonotic diseases. Such proactive measures are essential to anticipate and prevent future cases of human tularemia, ensuring a coordinated response to emerging public health threats.

Background: Brucellosis is a zoonotic bacterial disease that can affect humans and animals. It is often transmitted to humans through the consumption of contaminated animal products or by direct contact with infected animals. In Kenya, data on human and animal brucellosis are limited.

Methods: To investigate the seroprevalence and molecular prevalence of human brucellosis in Kenya, we randomly selected from the healthy participants with possible exposure to animals and animal products and randomly selected 348 out of 2,779 human blood samples, that were obtained from a larger longitudinal cohort study that investigated of dengue, chikungunya and Rift Valley Disease exposure in western (Kisumu) and coastal (Ukunda) Kenya.

Results: Our study included 126 males (36%), 222 females (64%) in different age categories, and 61 children aged 16 years and younger (18%), with an overall median age of 29.5 years (2- to 75-year age range). Samples were tested by Abnova Brucella IgG enzyme-linked immunosorbent assay (ELISA) Kit (KA0954). Of the tested individuals, anti-Brucella IgG antibodies were detected in 96 (28%) of 348 randomly selected participants. All samples yielded negative results in quantitative polymerase chain reaction (qPCR) analysis. There was no statistically significant correlation between Brucella exposure and study site, gender, age, socioeconomic status, ownership of particular livestock (sheep, goats, and cattle), or consumption of raw animal products. However, highly educated individuals were more likely to have Brucella exposure (odds ratio = 2.02, 1.20-3.41, p = 0.01).

Conclusion: In comparison to previous seroprevalence-based studies conducted in nonpastoral Kenyan communities, our study revealed relatively higher seropositivity. This article emphasizes the importance of conducting surveillance for brucellosis in urban areas. Urban brucellosis surveillance within the framework of One Health could serve as a baseline to guide future research on brucellosis in humans.

Background: Anthrax is a zoonotic infection caused by Bacillus anthracis, predominantly affecting livestock, and may be transmitted to humans through direct or indirect contact with infected animals.

Methods: This retrospective study included all children aged 0-18 years who presented to Erzurum City Hospital, a major regional referral center, between January 2019 and January 2020 and were either clinically diagnosed with anthrax or identified as high-risk contacts and received prophylaxis. Demographic, clinical, and laboratory data, as well as treatment regimens, were evaluated.

Results: A total of 13 children (median age: 9 years; range: 4-16) were included; 11 (84.6%) were male and 2 (15.4%) were female. All children were from rural areas; 10 (76.9%) had direct contact with sick animals or consumed contaminated animal products, and four (30.7%) asymptomatic children were evaluated due to a high-risk exposure. Cutaneous anthrax occurred in 9 (69.2%) patients, involving the hands (5/9, 55.5%), forearms (2/9, 22.2%), and feet (2/9, 22.2%), all of whom developed a characteristic black eschar. Cultures and PCR were negative in all cases, and diagnoses were based on clinical and epidemiological criteria. Prophylaxis consisted of oral ciprofloxacin; therapeutic regimens included ciprofloxacin or amoxicillin-clavulanate. No complications or deaths occurred during follow-up.

Conclusions: Anthrax should be considered in children with painless black-eschar lesions and a history of contact with infected animals in endemic regions. Early recognition and appropriate treatment may prevent complications.

Borrelia miyamotoi is a relapsing fever spirochete, first identified in Japan and later detected in various Ixodes species across the northern hemisphere. The pathogen was linked to human infections in North America, Europe, Asia, and Russia, causing symptoms ranging from flu-like illness to severe neurological damage. This study aimed to assess the presence of B. miyamotoi in Ixodes ricinus ticks collected from wildlife, dogs, and humans in Lombardy, Northern Italy, between 2020 and 2023. A total of 3,886 ticks were sampled, with a 1% positivity rate. The spirochete was detected in all life stages of ticks, with sequences 100% identical to European strains. The pathogen was found mostly in northern mountain regions. Although no human cases have been reported in Italy, these areas pose a potential risk due to high tourist activity.