A case series of post-infectious chikungunya myeloradiculoneuropathy.

Chikungunya fever is an arboviral illness caused by chikungunya virus (CHIKV) and transmitted by the bite of Aedes aegypti and Aedes albopictus. It is an RNA virus belonging to the genus Alphavirus and family Togaviridae. We present a case series of three patients with chikungunya illness developing para/post-infectious myeloradiculoneuropathy.These patients developed neurological symptoms in the form of bilateral lower limb weakness with sensory and bowel involvement after the recovery from the initial acute episode of chikungunya fever. Clinical examination findings suggested myeloradiculoneuropathy with normal Magnetic Resonance Imaging of the Spine, with the nerve conduction study showing sensorimotor axonal polyneuropathy. All the patients were treated with 1 g of methylprednisolone once a day for five days, and case 2 was given intravenous immunoglobulin also. In the follow-up, cases 1 and 2 showed complete recovery without recurrence, and case 3 did not show improvement at one month.

Role of auto-antibodies in the mechanisms of dengue pathogenesis and its progression: a comprehensive review.

A complex interaction among virulence factors, host-genes and host immune system is considered to be responsible for dengue virus (DENV) infection and disease progression. Generation of auto-antibodies during DENV infection is a major phenomenon that plays a role in the pathophysiology of dengue hemorrhagic fever and dengue shock syndrome. Hemostasis, thrombocytopenia, hepatic endothelial dysfunction, and autoimmune blistering skin disease (pemphigus) are different clinical manifestations of dengue pathogenesis; produced due to the molecular mimicry of DENV proteins with self-antigens like coagulation factors, platelets and endothelial cell proteins. This review elaborately describes the current advancements in auto-antibody-mediated immunopathogenesis which inhibits coagulation cascade and promotes hyperfibrinolysis. Auto-antibodies like anti-endothelial cell antibodies-mediated hepatic inflammation during severe DENV infection have also been discussed. Overall, this comprehensive review provides insight to target auto-antibodies that may act as potential biomarkers for disease severity, and a ground for the development of therapeutic strategy against DENV.

Dengue induced acute liver failure: A meta summary of case reports.

BACKGROUND: Dengue fever is the most common cause of viral hemorrhagic fever, with more than 400 million cases being reported annually, worldwide. Even though hepatic involvement is common, acute liver failure (ALF) is a rare complication of dengue fever. AIM: To analyze the demographic profile, symptomology, hospital course and outcomes of patients presenting with ALF secondary to dengue infection by reviewing the published case reports. METHODS: A systematic search was performed from multiple databases including PubMed, Reference Citation Analysis, Science Direct, and Google Scholar. The search terms used were "dengue" OR "severe dengue" OR "dengue shock syndrome" OR "dengue haemorrhagic syndrome" OR "dengue fever" AND "acute liver failure" OR "hepatic failure" OR "liver injury". The inclusion criteria were: (1) Case reports or case series with individual patient details; (2) Reported acute liver failure secondary to dengue infection; and (3) Published in English language and on adult humans. The data were extracted for patient demographics, clinical symptomatology, clinical interventions, hospital and intensive care unit course, need for organ support and clinical outcomes. RESULTS: Data from 19 case reports fulfilling the predefined inclusion criteria were included. The median age of patients was 38 years (inter quartile range: Q3-Q1 26.5 years) with a female preponderance (52.6%). The median days from diagnosis of dengue to development of ALF was 4.5 d. The increase in aspartate aminotransferase was higher than that in alanine aminotransferase (median 4625 U/L vs 3100 U/L). All the patients had one or more organ failure, with neurological failure present in 73.7% cases. 42.1% patients required vasopressor support and hepatic encephalopathy was the most reported complication in 13 (68.4%) cases. Most of the patients were managed conservatively and 2 patients were taken up for liver transplantation. Only 1 death was reported (5.3%). CONCLUSION: Dengue infection may rarely lead to ALF. These patients may frequently require intensive care and organ support. Even though most of these patients may improve with supportive care, liver transplantation may be a therapeutic option in refractory cases.

Ophthalmic manifestations as the first presenting feature in dengue fever: a 10-year study.

Purpose: To report patients who first presented with various ocular manifestations and eventually ascertained to have underlying dengue. Methods: A prospective study was conducted at multiple tertiary eye-care centers in India from 2012 to 2022. Cases reporting initially with ocular features along with fever/past history of fever over the last two weeks or with clinical features of dengue were selected. After an ophthalmological examination, patients underwent complete serological and biochemical analysis and those with reduced platelet counts were evaluated for dengue. Results: Out of 564 cases, 15 patients were verified to be afflicted with dengue eventually. A rising trend of cases was seen every year and out of 15 cases, eight cases were reported during the Covid-19 pandemic (from 2020 to 2022), but were COVID-negative. 9 cases presented with acute redness followed by diminished vision. Seven cases presented a history of fever over the last few days and one had traveled from dengue endemic area. The various ocular presentations included subconjunctival hemorrhage, viral keratitis, anterior uveitis, sixth-nerve palsy, and vitreous hemorrhage. On serological examination, all 15 patients were detected to have low platelets. All cases responded well with supportive treatment and the ocular features subsided in all within a couple of weeks with good visual recovery. Conclusion: In a tropical nation, such as India, with endemic dengue zones and increasing figures of dengue lately, ophthalmologists must include dengue fever among the differential diagnoses in various ocular presentations like subconjunctival hemorrhage, viral keratitis, anterior uveitis, sixth nerve palsy, and vitreous hemorrhage. Abbreviations: DHF = dengue hemorrhagic fever, PCR = polymerase chain reaction, RT-PCR = real-time automated reverse transcriptase (RT-PCR), SD = standard deviation, MAC-ELIS = IgM antibodies capture enzyme-linked immunosorbent assay, RE = right eye, LE = left eye, CECT = Contrast-enhanced computed tomography.

Concurrent infection of dengue virus with malaria parasites among outpatients attending healthcare facilities in Benin city, Nigeria.

Background: Dengue virus (DENV) and malaria parasites (MP) are among the common febrile diseases affecting the tropics and subtropics of the world. Both are mosquito-borne pathogens affecting humans and other animals. Methods: Blood samples were collected from 280 consented out-patients attending the selected hospitals and were analyzed. Malaria parasites were detected using microscopy and Malaria Ag Pf/Pan Rapid Test Device. Dengue virus was detected by serology and heminested reverse transcriptase PCR (hnRT-PCR) to target the flavivirus polymerase (NS5) gene. Results: Malaria parasites recorded a total positivity of 151 patients (53.9%) using microscopy, while DENV antibodies (DENV IgM and DENV IgG) were positive in 16 (5.7%) and 39 (13.9%) patients, respectively. There was a concurrent infection between MP/DENV IgM in 13 (4.6%) patients and MP/DENV IgG in 27 (9.6%) patients. Molecular identification revealed DENV serotype 2 in circulation. Conclusion: This study documents molecular evidence of dengue virus coexisting with malaria parasites in the study population, hence the need for efficient surveillance and control system.

Perceived needs of disease vector control programs: A review and synthesis of (sub)national assessments from South Asia and the Middle East.

Systems for disease vector control should be effective, efficient, and flexible to be able to tackle contemporary challenges and threats in the control and elimination of vector-borne diseases. As a priority activity towards the strengthening of vector control systems, it has been advocated that countries conduct a vector-control needs assessment. A review was carried out of the perceived needs for disease vector control programs among eleven countries and subnational states in South Asia and the Middle East. In each country or state, independent teams conducted vector control needs assessment with engagement of stakeholders. Important weaknesses were described for malaria, dengue and leishmaniases regarding vector surveillance, insecticide susceptibility testing, monitoring and evaluation of operations, entomological capacity and laboratory infrastructure. In addition, community mobilization and intersectoral collaboration showed important gaps. Countries and states expressed concern about insecticide resistance that could reduce the continued effectiveness of interventions, which demands improved monitoring. Moreover, attainment of disease elimination necessitates enhanced vector surveillance. Vector control needs assessment provided a useful planning tool for systematic strengthening of vector control systems. A limitation in conducting the vector control needs assessment was that it is time- and resource-intensive. To increase the feasibility and utility of national assessments, an abridged version of the guidance should focus on operationally relevant topics of the assessment. Similar reviews are needed in other regions with different contextual conditions.

Scrub typhus in pregnancy - A threat to maternal and fetal outcome.

Background and Objectives: Scrub typhus is an acute febrile illness transmitted by the bite of trombiculid mite in the larval stage. Scrub typhus is rare in pregnancy and there is paucity of data on the clinical outcome of scrub typhus during pregnancy. Material and Methods: We present five cases of scrub typhus complicating pregnancy who were admitted in the obstetric ward at AIIMS Rishikesh, India during the antenatal period for management. Results: The first patient presented at term pregnancy in semiconscious state while the rest were preterm between 31 and 34 weeks period of gestation. The age at presentation was 21-31 years. All five had febrile illness of >5 days' duration along with cough. Fever investigations like blood culture, peripheral smear for malarial parasite, dengue serology, widal test, and urine culture were negative. Serology for scrub typhus was positive in all. Once diagnosis was confirmed for scrub typhus, patients were given the drug of choice azithromycin 500 mg twice daily for five days. Scrub typhus complicating pregnancy led to maternal mortality in one patient. It resulted in one preterm delivery, one intrauterine fetal death, and rest three were delivered at term with good perinatal outcome. Conclusion: Scrub typhus is common in endemic areas like Uttarakhand, India. It has a poor fetal outcome. If diagnosed early and treatment started, maternal and fetal prognosis can be favorable. As large case series are unavailable in literature, it is difficult to predict the course of disease which at times may be fulminant.

APRI as a predictor of severe dengue fever.

Introduction: The AST/platelet ratio index (APRI) is a well-researched indicator of liver fibrosis. Some studies have shown that APRI can be used as a predictor of severe dengue, but the data is limited. As dengue epidemics are common in our country with limited healthcare resources, we believe APRI can help emergency physicians/primary physicians in predicting the severity of dengue and plan for the appropriate use of limited healthcare resources. Objective: 1) To determine the utility of APRI as a predictor of severe dengue. 2) To determine the association of APRI with length of hospital stay and platelet requirement. Materials and Methods: A retrospective cross-sectional study was done on patients presented to the Emergency Medicine department at Travancore Medicity Medical College with a positive Dengue NS1 antigen or IgM antibody. Results: We found from the univariate analysis results that ALT > 74.5 IU/L has a sensitivity of 59.6 and a specificity of 76.3 (AUC: 0.696; 95% CI: 0.606-0.786), AST > 160.5 IU/L has a sensitivity of 42.3 and a specificity of 93.7 (AUC: 0.747; 95% CI: 0.665-0.829), and APRI > 3.2 has a sensitivity of 69.2 and a specificity of 84.2 (AUC: 0.806; 95% CI: 0.72-0.884) to predict severe dengue. Patients with an APRI of >3.2 required a mean hospital stay of 5.47 days (P = 0.005); 27 (81.8%) requiring platelet transfusion had an APRI of > 3.2 (P = 0.00). Conclusion: APRI is a straightforward index that can be easily derived from AST and platelet values. APRI values of >3.2 can predict severe dengue with a sensitivity of 69.2 and a specificity of 84.2. APRI values of >3.2 are also associated with the length of hospital stay and requirement of platelet transfusion.

Transgenic line for characterizing GABA-receptor expression to study the neural basis of olfaction in the yellow-fever mosquito.

The mosquito Aedes aegypti is an important vector of diseases including dengue, Zika, chikungunya, and yellow fever. Olfaction is a critical modality for mosquitoes enabling them to locate hosts, sources of nectar, and sites for oviposition. GABA is an essential neurotransmitter in olfactory processing in the insect brain, including the primary olfactory center, the antennal lobe. Previous work with Ae. aegypti has suggested that antennal lobe inhibition via GABA may be involved in the processing of odors. However, little is known about GABA receptor expression in the mosquito brain, or how they may be involved in odor attraction. In this context, generating mutants that target the mosquito's olfactory responses, and particularly the GABAergic system, is essential to achieve a better understanding of these diverse processes and olfactory coding in these disease vectors. Here we demonstrate the potential of a transgenic line using the QF2 transcription factor, GABA-B1QF2-ECFP, as a new neurogenetic tool to investigate the neural basis of olfaction in Ae. aegypti. Our results show that the gene insertion has a moderate impact on mosquito fitness. Moreover, the line presented here was crossed with a QUAS reporter line expressing the green fluorescent protein and used to determine the location of the metabotropic GABA-B1 receptor expression. We find high receptor expression in the antennal lobes, especially the cell bodies surrounding the antennal lobes. In the mushroom bodies, receptor expression was high in the Kenyon cells, but had low expression in the mushroom body lobes. Behavioral experiments testing the fruit odor attractants showed that the mutants lost their behavioral attraction. Together, these results show that the GABA-B1QF2-ECFP line provides a new tool to characterize GABAergic systems in the mosquito nervous system.

CO-INFECTION OF DENGUE AND HEPATITIS A VIRUSES: A RARE CASE REPORT.

Dengue fever and hepatitis A are endemic infections caused by viruses that mostly affect developing countries (Volchkova et al., 2016). Co-infection is rare, and represents a diagnostic challenge due to their overlapping symptoms (Yakoob et al., 2009). The febrile syndrome accompanied by abdominal pain and vomiting are the common clinical manifestations of both pathologies. However, confirmation of diagnosis depends on laboratory tests ( Khetarpal and Khanna, 2016; Abutaleb and Kottilil, 2020). We report a case of a young female with dengue and hepatitis A co-infection.

Curcumin as a natural potential drug candidate against important zoonotic viruses and prions: A narrative review.

Zoonotic diseases are major public health concerns and undeniable threats to human health. Among Zoonotic diseases, zoonotic viruses and prions are much more difficult to eradicate, as they result in higher infections and mortality rates. Several investigations have shown curcumin, the active ingredient of turmeric, to have wide spectrum properties such as anti-microbial, anti-vascular, anti-inflammatory, anti-tumor, anti-neoplastic, anti-oxidant, and immune system modulator properties. In the present study, we performed a comprehensive review of existing in silico, in vitro, and in vivo evidence on the antiviral (54 important zoonotic viruses) and anti-prion properties of curcumin and curcuminoids in PubMed, Google Scholar, Science Direct, Scopus, and Web of Science databases. Database searches yielded 13,380 results, out of which 216 studies were eligible according to inclusion criteria. Of 216 studies, 135 (62.5%), 24 (11.1%), and 19 (8.8%) were conducted on the effect of curcumin and curcuminoids against SARS-CoV-2, Influenza A virus, and dengue virus, respectively. This review suggests curcumin and curcuminoids as promising therapeutic agents against a wide range of viral zoonoses by targeting different proteins and signaling pathways.

Molecular networking-based mass spectral identification of Brucea javanica (L.) Merr. metabolites and their selective binding affinities for dengue virus enzymes.

Brucea javanica, a valued traditional medicinal plant in Malaysia, known for its fever-treating properties yet remains underexplored for its potential antiviral properties against dengue. This study aims to simultaneously identify chemical classes and metabolites within B. javanica using molecular networking (MN), by Global Natural Product Social (GNPS), and SIRIUS in silico annotation. Liquid chromatography-mass spectrometry (LC-MS2)-based MN explores chemical diversity across four plant parts (leaves, roots, fruits, and stem bark), revealing diverse metabolites such as tryptophan-derived alkaloids, terpenoids, and octadecadenoids. Simultaneous LC-MS2 and MN analyses reveal a discriminative capacity for individual plant components, with roots accumulating tryptophan alkaloids, fruits concentrating quassinoids, leaves containing fusidanes, and stem bark primarily characterised by simple indoles. Subsequently, extracts were evaluated for dengue antiviral activity using adenosine triphosphate (ATP) and plaque assays, indicates potent efficacy in the dichloromethane (DCM) extract from roots (EC50 = 0.3 µg/mL, SI = 10). Molecular docking analysis of two major compounds; canthin-6-one (264) and 1-hydroxy-11-methoxycanthin-6-one (275) showed potential binding interactions with active sites of NS5 RNA-dependent RNA polymerase (RdRp) of dengue virus (DENV) protein. Subsequent in vitro evaluation revealed compounds 264 and 275 had a promising dengue antiviral activity with SI value of 63 and 1.85. These identified metabolites emerge as potential candidates for further evaluation in dengue antiviral activities.

Super epitope dengue vaccine instigated serotype independent immune protection in-silico.

Dengue becomes the most common life-threatening infectious arbovirus disease globally, with prevalence in the tropical and subtropical areas. The major clinical features include dengue haemorrhagic fever (DHF) and dengue shock syndrome (DSS), a condition of hypovolemic shock. Four different serotypes of the dengue virus, known as dengue virus serotype (DENV)- 1, 2, 3 and 4 can infect humans. Only one vaccine is available in the market, named Dengvaxia by Sanofi Pasteur, but there is no desired outcome of this treatment due the antibody dependent enhancement (ADE) of the multiple dengue serotypes. As of now, there is no cure against dengue disease. Our goal in this work was to create a subunit vaccine based on several epitopes that would be effective against every serotype of the dengue virus. Here, computational methods like- immunoinformatics and bioinformatics were implemented to find out possible dominant epitopes. A total of 21 epitopes were chosen using various in-silico techniques from the expected 133 major histocompatibility complex (MHC)- I and major histocompatibility complex (MHC)- II epitopes, along with 95 B-cell epitopes which were greatly conserved. Immune stimulant, non-allergenic and non-toxic immunodominant epitopes (super epitopes) with a suitable adjuvant (Heparin-Binding Hemagglutinin Adhesin, HBHA) were used to construct the vaccine. Following the physicochemical analysis, vaccine construct was docked with Toll-like receptors (TLRs) to predict the immune stimulation. Consequently, the optimal docked complex that demonstrated the least amount of ligand-receptor complex deformability was used to conduct the molecular dynamics analysis. By following the codon optimization, the final vaccine molecule was administered into an expressing vector to perform in-silico cloning. The robust immune responses were generated in the in-silico immune simulation analysis. Hence, this study provides a hope to control the dengue infections. For validation of the immune outcomes, in-vitro as well as in-vivo investigations are essential.

Dengue hospitalizations and in-hospital mortality changes in trend in Ecuador: a nationwide study from 2015 to 2022.

OBJECTIVE: This study aimed to analyze dengue hospitalizations and in-hospital mortality trends in Ecuador, along with sociodemographic factors influencing adverse outcomes. METHODS: This study included 31,616 dengue hospitalizations in Ecuador during 2015-2022, of which 115 (0.36%) died. Data were extracted from national hospital registries. Age adjusted rates were calculated, and for the analysis of changes in trend, a Joinpoint regression was performed. Multivariate binary and multinomial logistic regressions were performed for assessing sociodemographic factors influencing dengue adverse outcomes. RESULTS: During 2015-2022, the mean age adjusted dengue hospitalization rate was 22.3 per 100,000 inhabitants with 49.41% annual decrease during 2015-2017 and 31.73% annual increase during 2017-2022 with higher rates in 2020 with 31.61, 2021 with 34.42, and 2022 with 25.81. The mean dengue in-hospital mortality rate was 0.08, mortality rates did not show significant changes during 2015-2022. Higher probability of death was observed in ages ≥50 years and ethnic minorities. People living in rural areas exhibited a 64% higher risk for complicated dengue hospitalization. CONCLUSIONS: It was observed as an important accomplishment in Ecuador's ongoing efforts to improve healthcare regarding dengue. 0.36% of dengue hospitalizations ended in death which is below the recommended 1%. The increase in dengue hospitalizations in Ecuador during recent years remains a concern. The COVID-19 pandemic might have influenced dengue prevention and vector control to be neglected leading to an increase in cases.

Robustness in population-structure and demographic-inference results derived from the Aedes aegypti SNP chip and whole-genome sequencing data.

The mosquito Aedes aegypti is the primary vector of many human arboviruses such as dengue, yellow fever, chikungunya and Zika, which affect millions of people world-wide. Population genetics studies on this mosquito have been important in understanding its invasion pathways and success as a vector of human disease. The Axiom aegypti1 SNP chip was developed from a sample of geographically diverse Ae. aegypti populations to facilitate genomic studies on this species. We evaluate the utility of the Axiom aegypti1 SNP chip for population genetics and compare it with a low-depth shot-gun sequencing approach using mosquitoes from the native (Africa) and invasive range (outside Africa). These analyses indicate that results from the SNP chip are highly reproducible and have a higher sensitivity to capture alternative alleles than a low-coverage whole-genome sequencing approach. Although the SNP chip suffers from ascertainment bias, results from population structure, ancestry, demographic and phylogenetic analyses using the SNP chip were congruent with those derived from low coverage whole genome sequencing, and consistent with previous reports on Africa and outside Africa populations using microsatellites. More importantly, we identified a subset of SNPs that can be reliably used to generate merged databases, opening the door to combined analyses. We conclude that the Axiom aegypti1 SNP chip is a convenient, more accurate, low-cost alternative to low-depth whole genome sequencing for population genetic studies of Ae. aegypti that do not rely on full allelic frequency spectra. Whole genome sequencing and SNP chip data can be easily merged, extending the usefulness of both approaches.

Impact of climate change on dengue incidence in Singapore: time-series seasonal analysis.

This study aimed to identify the meteorological factors that contribute to dengue epidemics. The monthly incidence of dengue was used as the outcome variable, while maximum temperature, humidity, precipitation, and sunshine hours were used as independent variables. The results showed a consistent increase in monthly dengue cases from 2013 to 2021, with seasonal patterns observed in stationary time-series data. The ARIMA (2, 1, 3) × seasonal (0, 1, 2)12 model was used based on its lowest Akaike Information Criterion (AIC) values. The analysis revealed that a 1-unit increase in rainfall was positively correlated with a small 0.062-unit increase in dengue cases, whereas a 1-unit increase in humidity was negatively associated, leading to a substantial reduction of approximately 16.34 cases. This study highlights the importance of incorporating weather data into national dengue prevention programs to enhance public awareness and to promote recommended safety measures.

Characterization of the fragmentation mechanisms in electrospray ionization tandem mass spectrometry of chloroquinoline derivatives with larvicidal activity against Aedes aegypti.

RATIONALE: 4,7-Dichloroquinoline (DCQ) represents a group of synthetic molecules inspired by natural products with important roles in biological and biomedical areas. This work aimed to characterize DCQ and its derivatives by high-resolution electrospray ionization (ESI) mass spectrometry and tandem mass spectrometry (ESI-MS/MS), supported by theoretical calculations. Biological assays were carried out with DCQ and its derivatives to determine LC50 values against Aedes aegypti larvae. METHODS: Five DCQ derivatives were synthesized by using previously described protocols. ESI-MS/MS analyses were carried out with a quadrupole/time-of-flight and ion-trap instrument. The proposed gas-phase protonation sites and fragmentation were supported by density functional theory calculations. The larvicidal tests were performed with the Ae. aegypti Rockefeller strain, and the LC50 values were determined by employing five test concentrations. Larval mortality was determined after treatment for 48 h. RESULTS: DCQ bromides or aldehydes (C-3 or C-8 positions), as well as the trimethylsilyl derivative (C-3 position), were prepared. Detailed ESI-MS/MS data revealed heteroatom elimination through an exception to the even-electron rule, to originate open-shell species. Computational studies were used to define the protonation sites and fragmentation pathways. High activity of DCQ and its derivatives against Ae. aegypti larvae was demonstrated. CONCLUSION: Our results provided a well-founded characterization of the fragmentation reactions of DCQ and its derivatives, which can be useful for complementary studies of the development of a larvicidal product against Ae. aegypti.

Epidemiological investigation of dengue fever outbreak and its socioeconomic determinants in Banadir region, Somalia.

BACKGROUND: Dengue has become an alarming global problem and is endemic in many countries, particularly in tropical and subtropical countries. The aim of this study was to investigate dengue fever outbreak in Banadir Region, Somalia, to understand the risk factors (time, place, personal characteristics). METHODS: A descriptive cross-sectional study was undertaken to determine the levels of circulating anti-dengue virus antibodies and DENV NS1 antigen among Banadir Region residents, while a questionnaire survey was conducted to understand the clinical and demographic characteristics of the patients. RESULTS: A total of 735 febrile patients were studied, with 55.6% men and 44.3% women. The majority of the participants were children aged 14 years and younger. Among them, 10.8% tested positive for IgM antibodies against dengue virus (DENV), while the prevalence of DENV NS1 antigen was 11.8%. Fever and myalgia were the most common symptoms observed in the DENV-positive patients. CONCLUSIONS: A dengue fever outbreak has been confirmed in Banadir region, Somalia. This study provides information on the most affected districts and identifies risk factors contributing to DF outbreaks. The study recommends improving outbreak readiness and response, particularly in surveillance and laboratory diagnostics, by fostering intersectoral collaboration and establishing regulatory frameworks for financial and operational participation.

Long-term variations of urban-Rural disparities in infectious disease burden of over 8.44 million children, adolescents, and youth in China from 2013 to 2021: An observational study.

BACKGROUND: An accelerated epidemiological transition, spurred by economic development and urbanization, has led to a rapid transformation of the disease spectrum. However, this transition has resulted in a divergent change in the burden of infectious diseases between urban and rural areas. The objective of our study was to evaluate the long-term urban-rural disparities in infectious diseases among children, adolescents, and youths in China, while also examining the specific diseases driving these disparities. METHODS AND FINDINGS: This observational study examined data on 43 notifiable infectious diseases from 8,442,956 cases from individuals aged 4 to 24 years, with 4,487,043 cases in urban areas and 3,955,913 in rural areas. The data from 2013 to 2021 were obtained from China's Notifiable Infectious Disease Surveillance System. The 43 infectious diseases were categorized into 7 categories: vaccine-preventable, bacterial, gastrointestinal and enterovirus, sexually transmitted and bloodborne, vectorborne, zoonotic, and quarantinable diseases. The calculation of infectious disease incidence was stratified by urban and rural areas. We used the index of incidence rate ratio (IRR), calculated by dividing the urban incidence rate by the rural incidence rate for each disease category, to assess the urban-rural disparity. During the nine-year study period, most notifiable infectious diseases in both urban and rural areas exhibited either a decreased or stable pattern. However, a significant and progressively widening urban-rural disparity in notifiable infectious diseases was observed. Children, adolescents, and youths in urban areas experienced a higher average yearly incidence compared to their rural counterparts, with rates of 439 per 100,000 compared to 211 per 100,000, respectively (IRR: 2.078, 95% CI [2.075, 2.081]; p < 0.001). From 2013 to 2021, this disparity was primarily driven by higher incidences of pertussis (IRR: 1.782, 95% CI [1.705, 1.862]; p < 0.001) and seasonal influenza (IRR: 3.213, 95% CI [3.205, 3.220]; p < 0.001) among vaccine-preventable diseases, tuberculosis (IRR: 1.011, 95% CI [1.006, 1.015]; p < 0.001), and scarlet fever (IRR: 2.942, 95% CI [2.918, 2.966]; p < 0.001) among bacterial diseases, infectious diarrhea (IRR: 1.932, 95% CI [1.924, 1.939]; p < 0.001), and hand, foot, and mouth disease (IRR: 2.501, 95% CI [2.491, 2.510]; p < 0.001) among gastrointestinal and enterovirus diseases, dengue (IRR: 11.952, 95% CI [11.313, 12.628]; p < 0.001) among vectorborne diseases, and 4 sexually transmitted and bloodborne diseases (syphilis: IRR 1.743, 95% CI [1.731, 1.755], p < 0.001; gonorrhea: IRR 2.658, 95% CI [2.635, 2.682], p < 0.001; HIV/AIDS: IRR 2.269, 95% CI [2.239, 2.299], p < 0.001; hepatitis C: IRR 1.540, 95% CI [1.506, 1.575], p < 0.001), but was partially offset by lower incidences of most zoonotic and quarantinable diseases in urban areas (for example, brucellosis among zoonotic: IRR 0.516, 95% CI [0.498, 0.534], p < 0.001; hemorrhagic fever among quarantinable: IRR 0.930, 95% CI [0.881, 0.981], p = 0.008). Additionally, the overall urban-rural disparity was particularly pronounced in the middle (IRR: 1.704, 95% CI [1.699, 1.708]; p < 0.001) and northeastern regions (IRR: 1.713, 95% CI [1.700, 1.726]; p < 0.001) of China. A primary limitation of our study is that the incidence was calculated based on annual average population data without accounting for population mobility. CONCLUSIONS: A significant urban-rural disparity in notifiable infectious diseases among children, adolescents, and youths was evident from our study. The burden in urban areas exceeded that in rural areas by more than 2-fold, and this gap appears to be widening, particularly influenced by tuberculosis, scarlet fever, infectious diarrhea, and typhus. These findings underscore the urgent need for interventions to mitigate infectious diseases and address the growing urban-rural disparity.

Modulation of immune responses in the central nervous system by Zika virus, West Nile virus, and dengue virus.

Arthropod-borne viruses (arboviruses) pose significant threats to global public health by causing a spectrum of diseases ranging from mild febrile illnesses to severe neurological complications. Understanding the intricate interplay between arboviruses and the immune system within the central nervous system is crucial for developing effective strategies to combat these infections and mitigate their neurological sequelae. This review comprehensively explores the mechanisms by which arboviruses such as Zika virus, West Nile virus, and Dengue virus manipulate immune responses within the CNS, leading to diverse clinical manifestations.