Pathogens and Global Health最新文献

It is now a well-known fact that antibiotic resistance in bacteria has increased with the widespread and uncontrolled use of antibiotics. However, the increase in antibiotic resistance should not be attributed solely to the use of antibiotics. Other antimicrobial agents used in the control of bacterial infections and even heavy metals are also among the factors causing an increase in antibiotic resistance. It is therefore important to study the effects of these agents on bacterial cells. It is generally believed that the selection of resistance typically occurs at high concentrations of antibiotics. However, accumulating evidence demonstrates that selection can also occur at sub-inhibitory levels, making it essential to better understand their impact. While most studies have focused on antibiotics, fewer have examined the influence of biocides, heavy metals, and bioactive components. In this review, we discuss how low concentrations of these agents not only contribute to the development of resistance but also modulate bacterial virulence by affecting biofilm formation, siderophore production, cell morphology, and gene expression. A comprehensive literature review has been conducted, highlighting both the potential risks of these agents in resistance development and their implications for bacterial virulence in the future.

Dengue fever, the most prevalent mosquito-borne viral disease, has experienced a tenfold increase in incidence over the past two decades, posing a significant global public health challenge. In 2023, more than five million cases and over 5000 dengue-related deaths were recorded, with exceeding numbers in 2024. This narrative review provides a comprehensive summary of the current epidemiology, clinical features, diagnostic methods, prevention and management strategies for dengue fever, with a particular focus on the influence of climate changes and human activities on the spread of this vector-borne disease. Factors such as climate change, urbanization, and population movements have contributed to the expanding geographic distribution and increased incidence of dengue. Additionally, this review highlights the challenges associated with accurate disease surveillance and underscores the importance of integrated strategies-including climate-adaptive surveillance, vector control, and public health policies-to mitigate the impact of dengue. This information is essential for clinicians and policymakers to implement effective surveillance and prevention measures, ultimately reducing the incidence and burden on public health.

Whole-genome sequencing, supported on short-read-sequencing, has revolutionized the precision to track Mycobacterium tuberculosis (MTB) transmission. However, the complexity of the MTB genome (10% repetitive regions and 65% GC content) challenges short-read mapping and assembly, leading to the exclusion of certain genomic regions from the analysis. Long-read sequencing can overcome these limitations, giving access to these regions, generally uninterrogated. Our study aims to evaluate the potential of long-read sequencing in redefining long-term MTB transmission clusters, previously characterized by short-read sequencing. We selected 78 cases from eight long-term clusters (5-17 years; 7 to 16 cases), from a population-based genomic epidemiology program in Almería, Spain. The clusters were carefully selected to ensure cases i) infected by identical strains (0 SNPs), ii) exhibiting pairwise-SNP-based distances from 1 to 16 SNPs and iii) distributed along different branches in the genomic networks. Long-read analysis increased the distances of each cluster from the reference by an average of 258 SNPs and intercluster distances by 113 SNPs. Within-cluster diversity also increased, with pairwise distances rising from 1 to 22 SNPs across 1-7 network branches. In one cluster, the acquisition of diversity led to overpass the 12-SNP threshold to consider a transmission cluster. Additionally, in four clusters, 1-2 cases previously classified as infected by identical strains were now reclassified due to the identification of additional SNP differences. Thanks to the identification of new diversity between the cases we could identify index cases, reconstruct transmission chronologies, precise patient-to-patient relationships and propose new epidemiological interpretations among the cases in cluster.

Early detection and effective management of malaria are crucial for elimination efforts. Microscopy and rapid diagnostic tests (RDTs) have been the main diagnostic methods for over fifteen years, but they have limitations, especially in cases of low parasite density or deletions of target markers (HRP2/3). This study compares the diagnostic performance of a novel hemozoin-based diagnostic assay (Hz-MOD) with RDTs for detecting malaria in febrile patients in southwestern India. A prospective observational study involved 480 patients screened with Hz-MOD, RDT, microscopy, and nested PCR. Among the samples, 121 were positive by both microscopy and PCR. The sensitivity of Hz-MOD was 94.21% compared to microscopy and 91.74% compared to PCR. For RDTs, sensitivity was 90.91% compared to microscopy and 87.60% compared to PCR. In terms of specificity, Hz-MOD showed 98.61% compared to microscopy and 97.77% compared to PCR, while RDTs had 100% specificity against microscopy and 98.89% against PCR. These results suggest that the hemozoin-based test demonstrates similar sensitivity to RDTs and could serve as an effective screening tool for malaria detection.

The global expansion of mosquito-borne diseases such as dengue, chikungunya, Zika, and West Nile virus is a major public health concern, intensified by climate change and environmental alterations. Aedes aegypti, Aedes albopictus, and Culex pipiens are among the most important vectors for these pathogens, contributing to their transmission across increasingly broad geographic areas. In Europe, the expanding distribution and vectorial competence of Ae. albopictus and Cx. pipiens highlight the need for innovative control strategies beyond traditional chemical and mechanical interventions, which face growing limitations due to resistance and sustainability concerns. This review examines the potential of radiofrequency (RF) exposure as a novel method to disrupt mosquito development and reduce vector competence. While the biological effects of RF have been studied in other systems, its impact on mosquito physiology and pathogen transmission remains underexplored. Preliminary findings suggest that RF exposure may alter larval viability, adult emergence, and reproductive capacity, with possible downstream effects on pathogen replication and transmission. We contextualize RF-based approaches alongside other emerging biocontrol strategies, including Wolbachia-based methods, genetic modification, and sterile insect techniques, emphasizing their integration into climate-responsive vector control programs. Additional consideration is given to other arthropod vectors of medical relevance, such as sandflies (Phlebotominae) and biting midges (Culicoides spp.), which contribute to the spread of arboviruses. Finally, we identify research gaps and propose directions for interdisciplinary studies to evaluate the feasibility, efficacy, and ecological impact of RF-based interventions. By targeting mosquito competence through non-chemical, scalable technologies, RF exposure offers a promising avenue to strengthen arbovirus prevention in the context of climate-driven vector expansion.

Shigellosis is a leading cause of diarrheal mortality worldwide. Shigella boydii is one of four Shigella species that contributes to this burden, however studies on S. boydii are limited. Here we combined epidemiological and genomic data to better understand S. boydii circulating both in Australia and globally. Between 1991 and 2019, there were 294 cases of S. boydii infections notified to the National Notifiable Diseases Surveillance System by Australian states and territories, with an increasing trend in notifications observed from 2013. Of cases whose place of acquisition was known, 54% (111/206) were acquired overseas, mainly from South-East Asia (57%; 63/111). Our genomic analysis included 250 S. boydii isolates: 44 from Victoria, Australia spanning 22 years (2001-2022) and 206 international isolates spanning 91 years (1930-2020). Phylogenomic analyses identified five major S. boydii phylogenetic lineages circulating globally. The Australian isolates were distributed across all five lineages, but the highest proportion was in Lineage 3. Antimicrobial resistance was common in both international and Australian isolates with > 60% of isolates classified as multi-drug-resistant. Resistance to the main clinically relevant antimicrobials was rare in S. boydii. Ciprofloxacin resistance was detected in seven S. boydii, however reduced susceptibility to ciprofloxacin was detected in 56 isolates and found in both Australian and international data. Importantly, resistance mechanisms to third-generation cephalosporins and macrolides were also detected. This study is the largest genomic analysis of S. boydii to date, providing insights into the population structure, epidemiology and emerging AMR threats in this neglected Shigella species.

Recent outbreaks of H5N1 avian influenza have exposed persistent weaknesses in global pandemic preparedness. Despite scientific advances, surveillance remains fragmented, hospital surge capacity is declining, and frontline workers continue to face inadequate protection. In low-income settings, delayed outbreak detection - exemplified by cholera in Sudan and mpox in central Africa - reflects ongoing gaps in diagnostic access and communication infrastructure. These challenges are compounded by geopolitical instability, fragile supply chains, and a lack of transparent, sustained investment in preparedness. While emerging tools like artificial intelligence offer promise for early warning and response, their impact depends on equitable integration across health systems. Rather than addressing pandemic threats through fragmented national strategies, a shift toward coordinated, inclusive global action is urgently needed. This Commentary highlights key vulnerabilities and proposes strategies to strengthen collective readiness for future infectious disease emergencies - emphasizing that pandemic preparedness is not solely a scientific issue, but a political and moral imperative.

Sustained by urbanization, globalization and climate change, infectious diseases transmitted by arthropod vectors, such as mosquitoes, ticks and sandflies, are emerging or resurging in Europe, including Italy. There are limited therapeutic treatments and vaccines for most arthropod-borne pathogens, thus monitoring and control of vectors remains the most-effective prevention strategy. Supported by a country-wide initiative that aims at providing strategic guidance for preventing vector-borne diseases in Italy, including suirveillance and control initiatives that results in the acquistion of a large number of field samples, we conceived a digital repository of samples from arthropod vectors and their metadata to promote their sharing among the scientific community. We built a relational database called RAV-IT, accessible at https://mosqit.unipv.it/. Currently, RAV-IT aggregates seventeen Italian institutions and hosts nearly two thousand vector samples and their metadata, which can be viewed and requested for research purposes. RAV-IT is interactive and can accept further samples from any users. RAV-IT is a non-profit repository that is expected to enhance resource sharing for research on arthropod vectors.

Background: With increased Chinese enterprises involvement in Sierra Leone under the Belt and Road Initiative, understanding the prevalence of infectious diseases among local populations, particularly employees of Chinese firms, is crucial for enterprise management and public health interventions. This cross-sectional study aimed to assess the seroprevalence of HIV, HBV, HCV, syphilis, malaria, and tuberculosis among the local population, including co-infection prevalence and associated risk factors.

Methods: A serological survey was conducted among 342 local employees from six Chinese enterprises and 165 community residents (controls). Blood samples were tested using rapid immunological kits. Demographic data, occupational details, body temperature, and blood pressure were collected. Seroprevalence rates and risk factors were analyzed, with a focus on co-infections.

Results: The seroprevalence rates, in descending order, were as follows: malaria parasites (14.6%, 95% CI: 11.64%-17.97%), HBV (10.1%, 95% CI: 7.58%-13.01%), HIV (6.1%, 95% CI: 4.20%-8.57%), tuberculosis (4.3%, 95% CI: 2.74%-6.50%), syphilis (3.7%, 95% CI: 2.27%-5.79%), and HCV (0.0%, NA) for both the company employees and community residents. For mono-infection, there is a significantly lower seroprevalence in HIV and syphilis among company employees than in community controls (4.4% vs 9.7%, p = 0.019; 2.3% vs 6.7%, p = 0.016). Both the co-infection rate (3.5% vs 8.5%, p = 0.017) and the overall infection rate (29.8% vs 39.4%, p = 0.032) are also significantly lower among company employees compared to community controls.

Conclusion: This study provides insights into the prevalence of infectious diseases and co-infection levels among local employees of Chinese enterprises and community residents in Sierra Leone. It highlights the importance of pre-employment screenings and post-employment health evaluations. The findings underscore the need for broader epidemiological investigations and surveillance to combat infectious diseases in sub-Saharan Africa effectively.