-
Life Science Alliance Aug 2024Dengue fever, a neglected tropical arboviral disease, has emerged as a global health concern in the past decade. Necessitating a nuanced comprehension of the intricate...
Dengue fever, a neglected tropical arboviral disease, has emerged as a global health concern in the past decade. Necessitating a nuanced comprehension of the intricate dynamics of host-virus interactions influencing disease severity, we analysed transcriptomic patterns using bulk RNA-seq from 112 age- and gender-matched NS1 antigen-confirmed hospital-admitted dengue patients with varying severity. Severe cases exhibited reduced platelet count, increased lymphocytosis, and neutropenia, indicating a dysregulated immune response. Using bulk RNA-seq, our analysis revealed a minimal overlap between the differentially expressed gene and transcript isoform, with a distinct expression pattern across the disease severity. Severe patients showed enrichment in retained intron and nonsense-mediated decay transcript biotypes, suggesting altered splicing efficiency. Furthermore, an up-regulated programmed cell death, a haemolytic response, and an impaired interferon and antiviral response at the transcript level were observed. We also identified the potential involvement of the gene among others in the innate immune response during dengue viral pathogenesis, warranting further investigation. These findings provide valuable insights into potential therapeutic targets, underscoring the importance of exploring transcriptomic landscapes between different disease sub-phenotypes in infectious diseases.
Topics: Humans; Alternative Splicing; Female; Male; Dengue Virus; Adult; Severe Dengue; Middle Aged; Transcriptome; RNA-Binding Proteins; Gene Expression Profiling; Immunity, Innate; Dengue; Young Adult; Severity of Illness Index; Host-Pathogen Interactions
PubMed: 38830771
DOI: 10.26508/lsa.202402683 -
PLoS Neglected Tropical Diseases Jun 2024Dengue, Zika, and chikungunya, whose viruses are transmitted mainly by Aedes aegypti, significantly impact human health worldwide. Despite the recent development of...
BACKGROUND
Dengue, Zika, and chikungunya, whose viruses are transmitted mainly by Aedes aegypti, significantly impact human health worldwide. Despite the recent development of promising vaccines against the dengue virus, controlling these arbovirus diseases still depends on mosquito surveillance and control. Nonetheless, several studies have shown that these measures are not sufficiently effective or ineffective. Identifying higher-risk areas in a municipality and directing control efforts towards them could improve it. One tool for this is the premise condition index (PCI); however, its measure requires visiting all buildings. We propose a novel approach capable of predicting the PCI based on facade street-level images, which we call PCINet.
METHODOLOGY
Our study was conducted in Campinas, a one million-inhabitant city in São Paulo, Brazil. We surveyed 200 blocks, visited their buildings, and measured the three traditional PCI components (building and backyard conditions and shading), the facade conditions (taking pictures of them), and other characteristics. We trained a deep neural network with the pictures taken, creating a computational model that can predict buildings' conditions based on the view of their facades. We evaluated PCINet in a scenario emulating a real large-scale situation, where the model could be deployed to automatically monitor four regions of Campinas to identify risk areas.
PRINCIPAL FINDINGS
PCINet produced reasonable results in differentiating the facade condition into three levels, and it is a scalable strategy to triage large areas. The entire process can be automated through data collection from facade data sources and inferences through PCINet. The facade conditions correlated highly with the building and backyard conditions and reasonably well with shading and backyard conditions. The use of street-level images and PCINet could help to optimize Ae. aegypti surveillance and control, reducing the number of in-person visits necessary to identify buildings, blocks, and neighborhoods at higher risk from mosquito and arbovirus diseases.
Topics: Aedes; Animals; Brazil; Humans; Mosquito Vectors; Dengue; Cities; Mosquito Control; Image Processing, Computer-Assisted; Zika Virus Infection
PubMed: 38829905
DOI: 10.1371/journal.pntd.0011811 -
PLoS Neglected Tropical Diseases Jun 2024The first dengue outbreak in Sao Tome and Principe was reported in 2022. Entomological investigations were undertaken to establish the typology of Aedes larval habitats,...
BACKGROUND
The first dengue outbreak in Sao Tome and Principe was reported in 2022. Entomological investigations were undertaken to establish the typology of Aedes larval habitats, the distribution of Ae. aegypti and Ae. albopictus, the related entomological risk and the susceptibility profile of Ae. aegypti to insecticides, to provide evidence to inform the outbreak response.
METHODOLOGY/PRINCIPAL FINDINGS
Entomological surveys were performed in all seven health districts of Sao Tome and Principe during the dry and rainy seasons in 2022. WHO tube and synergist assays using piperonyl butoxide (PBO) and diethyl maleate (DEM) were carried out, together with genotyping of F1534C/V1016I/V410L mutations in Ae. aegypti. Aedes aegypti and Ae. albopictus were found in all seven health districts of the country with high abundance of Ae. aegypti in the most urbanised district, Agua Grande. Both Aedes species bred mainly in used tyres, discarded tanks and water storage containers. In both survey periods, the Breteau (BI > 50), house (HI > 35%) and container (CI > 20%) indices were higher than the thresholds established by WHO to indicate high potential risk of dengue transmission. The Ae. aegypti sampled were susceptible to all insecticides tested except dichlorodiphenyltrichloroethane (DDT) (9.2% mortality, resistant), bendiocarb (61.4% mortality, resistant) and alpha-cypermethrin (97% mortality, probable resistant). A full recovery was observed in Ae. aegypti resistant to bendiocarb after pre-exposure to synergist PBO. Only one Ae. aegypti specimen was found carrying F1534C mutation.
CONCLUSIONS/SIGNIFICANCE
These findings revealed a high potential risk for dengue transmission throughout the year, with the bulk of larval breeding occurring in used tyres, water storage and discarded containers. Most of the insecticides tested remain effective to control Aedes vectors in Sao Tome, except DDT and bendiocarb. These data underline the importance of raising community awareness and implementing routine dengue vector control strategies to prevent further outbreaks in Sao Tome and Principe, and elsewhere in the subregion.
Topics: Aedes; Animals; Dengue; Insecticides; Mosquito Vectors; Disease Outbreaks; Insecticide Resistance; Larva; Humans; Piperonyl Butoxide; Female; Maleates; Ecosystem; Dengue Virus
PubMed: 38829904
DOI: 10.1371/journal.pntd.0011903 -
Le Infezioni in Medicina 2024Dengue fever is a mosquito-borne viral infection that continues to pose a significant public health threat globally, including Nigeria. Here, we provided a review of... (Review)
Review
Dengue fever is a mosquito-borne viral infection that continues to pose a significant public health threat globally, including Nigeria. Here, we provided a review of dengue fever outbreaks in Nigeria from 1972 to 2023, examining the epidemiology, prevention strategies, challenges faced in combating the disease, and recommendations to mitigate its spread and transmission. We utilized scholarly databases such as PubMed and Google Scholar in writing this paper. The search keywords like, "dengue fever", "break-bone fever", "dengue fever virus" "outbreak", "Nigeria", "prevalence", and "epidemiology", were used to get appropriate published articles about the subject areas. Over the past five decades, Nigeria has experienced intermittent outbreaks of dengue fever, with varying degrees of severity and geographic distribution. Factors such as urbanization, climate change, and inadequate healthcare infrastructure have contributed to the resurgence and spread of the disease in the country. Despite efforts to control dengue transmission through vector control measures and public health interventions, challenges persist, including limited surveillance capacity, diagnostic delays, and gaps in vector control strategies. The emergence of new dengue virus serotypes and the potential for co-circulation with other arboviruses further complicate control efforts. This review highlights the importance of strengthening surveillance systems, enhancing vector control measures, improving diagnostic capabilities, and increasing public awareness to effectively mitigate the burden of dengue fever in Nigeria. Collaboration between government agencies, healthcare providers, researchers, and international partners is crucial in addressing the growing threat of dengue fever and reducing its impact on public health in Nigeria.
PubMed: 38827833
DOI: 10.53854/liim-3202-5 -
Le Infezioni in Medicina 2024Dengue is a vector-borne disease, especially important in tropical and subtropical areas. The first presentation of many arboviral diseases occurred mainly in animals,... (Review)
Review
INTRODUCTION
Dengue is a vector-borne disease, especially important in tropical and subtropical areas. The first presentation of many arboviral diseases occurred mainly in animals, including multiple and , such as dengue.
OBJECTIVE
To determine the serological and molecular frequency of the dengue virus in animals.
METHODS
A systematic literature review was carried out in five databases for the proportion of animals infected with dengue, defined by molecular and serological tests. A meta-analysis was performed using a random-effects model to calculate the pooled prevalence and 95% confidence intervals (CI). Cochran?s Q test and the I2 statistic were used to assess the heterogeneity between the two studies.
RESULTS
The presence of dengue in bats, primates, birds, sheep, horses, cattle, pigs, rodents and buffaloes, according to serological methods, had a prevalence of 10%, 29%, 8%, 1%, 11%, 0%, 49%, 2%, 7%, respectively. According to molecular methods, the presence of dengue in bats had a seroprevalence of 6.0%.
CONCLUSION
The present study confirms the presence of the Dengue virus in a large group of animal species, with potential implications as possible reservoirs of this virus, raising the possibility of zoonotic transmission.
PubMed: 38827825
DOI: 10.53854/liim-3202-7 -
Scientific Reports May 2024In flaviviruses such as Dengue or Zika, non-structural (NS) NS4A protein forms homo-oligomers, participates in membrane remodelling and is critical for virulence. In...
In flaviviruses such as Dengue or Zika, non-structural (NS) NS4A protein forms homo-oligomers, participates in membrane remodelling and is critical for virulence. In both viruses, mature NS4A has the same length and three predicted hydrophobic domains. The oligomers formed by Dengue NS4A are reported to be small (n = 2, 3), based on denaturing SDS gels, but no high-resolution structure of a flavivirus NS4A protein is available, and the size of the oligomer in lipid membranes is not known. Herein we show that crosslinking Zika NS4A protein in lipid membranes results in oligomers at least up to hexamers. Further, sedimentation velocity shows that NS4A in mild detergent C14-betaine appears to be in fast equilibrium between at least two species, where one is smaller, and the other larger, than a trimer or a tetramer. Consistently, sedimentation equilibrium data was best fitted to a model involving an equilibrium between dimers (n = 2) and hexamers (n = 6). Overall, the large, at least hexameric, oligomers obtained herein in liposomes and in mild detergent are more likely to represent the forms of NS4A present in cell membranes.
Topics: Liposomes; Viral Nonstructural Proteins; Detergents; Zika Virus; Protein Multimerization
PubMed: 38822066
DOI: 10.1038/s41598-024-63407-y -
Journal of Infection and Public Health Jul 2024We aimed to describe the landscape, including molecular, epidemiological, and clinical aspects of CHIKV infections in the Ribeirao Preto region, an area endemic to...
We aimed to describe the landscape, including molecular, epidemiological, and clinical aspects of CHIKV infections in the Ribeirao Preto region, an area endemic to dengue. We randomly screened 3744 plasma samples that had undergone DENV diagnosis to evaluate CHIKV-RNA using an in-house RT-PCR assay. Positive samples were followed clinically, and RNA samples were submitted to whole genome sequencing. Seventeen cases (0.5 %) were positive for CHIKV-RNA despite being negative for DENV-RNA. Notably, half of the patients experienced prolonged arthralgia lasting more than 90 days. Compared with the healthy control group, leukopenia and thrombocytopenia were observed in all CHIKV-positive individuals with statistically significant P values (P < 0.0001 and P = 0.0003, respectively). The genomic analysis revealed that the CHIKV strains being studied are classified within the East-Central-South-African (ECSA) genotype. This analysis identified new mutations, E1: K211E and E2: V264A, while the previously known mutation E1: A226V was not detected among these strains. This study highlights the need for epidemiological surveillance and preparedness for potential CHIKV epidemics in Brazil, particularly where other arboviruses co-circulate.
Topics: Humans; Brazil; Chikungunya Fever; Chikungunya virus; Dengue; Male; Female; Adult; Genotype; Middle Aged; RNA, Viral; Young Adult; Endemic Diseases; Adolescent; Whole Genome Sequencing; Aged; Child; Phylogeny; Mutation; Child, Preschool; Dengue Virus; Thrombocytopenia
PubMed: 38820892
DOI: 10.1016/j.jiph.2024.04.026 -
Cell Reports May 2024Flaviviruses such as dengue virus (DENV), Zika virus (ZIKV), and yellow fever virus (YFV) are spread by mosquitoes and cause human disease and mortality in tropical...
Flaviviruses such as dengue virus (DENV), Zika virus (ZIKV), and yellow fever virus (YFV) are spread by mosquitoes and cause human disease and mortality in tropical areas. In contrast, Powassan virus (POWV), which causes severe neurologic illness, is a flavivirus transmitted by ticks in temperate regions of the Northern hemisphere. We find serologic neutralizing activity against POWV in individuals living in Mexico and Brazil. Monoclonal antibodies P002 and P003, which were derived from a resident of Mexico (where POWV is not reported), neutralize POWV lineage I by recognizing an epitope on the virus envelope domain III (EDIII) that is shared with a broad range of tick- and mosquito-borne flaviviruses. Our findings raise the possibility that POWV, or a flavivirus closely related to it, infects humans in the tropics.
PubMed: 38819991
DOI: 10.1016/j.celrep.2024.114298 -
New Microbes and New Infections 2024
PubMed: 38818244
DOI: 10.1016/j.nmni.2024.101431 -
Heliyon May 2024The roles of antibodies secreted by subsets of B cells in dengue virus (DENV) infection have been extensively studied, yet, the contribution of tissue-homing B cells to...
The roles of antibodies secreted by subsets of B cells in dengue virus (DENV) infection have been extensively studied, yet, the contribution of tissue-homing B cells to antiviral immunity remains unclear. In this study, we performed a comprehensive analysis of B cell subpopulations in peripheral blood samples from DENV-infected patients using single-cell RNA-sequencing (scRNA-seq) datasets and flow cytometry. We showed that plasma cells (PCs) and plasmablasts (PBs) were the predominant B cell populations during the acute phase of secondary natural DENV infection, but not in convalescent phase nor in healthy controls. Interestingly, these cells expressed proliferation, adhesion, and tissue-homing genes, including , a homing marker of the skin, the initial infected site of DENV. Flow cytometry analysis confirmed a significant upregulation of cell surface expression of a cutaneous lymphocyte-associated antigen (CLA) encoded by in PCs and PBs, compared to naive and memory B cells from the same patients. The analysis of an independent single-cell B-cell receptor sequencing (scBCR-seq) dataset of DENV-infected patients revealed that the peripheral blood PCs and PBs exhibited the highest clonal expansion in secondary DENV infection compared to other B cell subsets. These clonally expanded cells also expressed the highest levels of tissue-homing genes, including In addition, by utilizing a public scRNA-seq dataset of SARS-CoV2 infection, we demonstrated the upregulation of several tissue-homing genes in PCs and PBs. Our study provides evidence for the potential roles of tissue-homing B cell subsets in the context of immune responses against viral infections in humans.
PubMed: 38818157
DOI: 10.1016/j.heliyon.2024.e30314