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Mosquitoes have numerous illnesses and are one of the deadliest animals in the planet. Including Zika, dengue, palaria, West Niles, chikungunya, yellow fever, and more, mosquitoborne illnesses. Various areas suffer from various climate-induced mosquito-borne illnesses, kinds of mosquitoes widespread across the region and access to preventive measures and medicines. Dengue fever is a mosquito-borne disease that is transferred to the dengue virus via the bite of an Aedes mosquito. The bits of the infected female Aedes mosquito, which spreads the virus to others as it feeds on the infected people's blood. Transmission of dengue is susceptible to climate due to many causes, such as temperature, humidity, precipitation, etc. Areas with higher vapor pressure and precipitation rates are more prone to dengue illness transmission. We utilized the classification algorithms to discover the essential characteristics that spread the dengue. Machine learning is one of the most important approaches of current analysis. For medical applications, many algorithms were employed. Dengue disease is one of the worst infectious diseases that require a high level machine to develop good models in order to learn. We employed the Ensemble Machine Learning technique in hybrid integrations to identify characteristics associated with the spread of the Dengue illness and achieve improved performance.

The most severe consequences of dengue virus infection include shock, haemorrhage, and major organ failure; however, the frequency of these manifestations varies, and the relative contribution of pre-existing anti-dengue virus antibodies, virus characteristics, and host factors (including age and comorbidities) are not well understood. Reliable characterisation of the epidemiology of severe dengue first depends on the use of consistent definitions of disease severity. As vaccine trials have shown, severe dengue is a crucial interventional endpoint, yet the infrequency of its occurrence necessitates the inclusion of thousands of study participants to appropriately compare its frequency among participants who have and have not been vaccinated. Hospital admission is frequently used as a proxy for severe dengue; however, lack of specificity and variability in clinical practices limit the reliability of this approach. Although previous infection with a dengue virus is the best characterised risk factor for developing severe dengue, the influence of the timing between dengue virus infections and the sequence of dengue virus infections on disease severity is only beginning to be elucidated. To improve our understanding of the diverse factors that shape the clinical spectrum of disease resulting from dengue virus infection, prospective, community-based and clinic-based immunological, virological, genetic, and clinical studies across a range of ages and geographical regions are needed.

Background: Aedes aegypti is the primary dengue vector, a significant public health problem in many countries. Controlling the growth of Ae. aegypti is the biggest challenge in the mosquito control program, and there is a need for finding bioactive molecules to control Ae. aegypti in order to prevent dengue virus transmission. Objective: To assess the mosquitocidal property of lawsone and its 3-methyl-4H-chromen-3-yl-1-phenylbenzo[6,7]chromeno[2,3,c]pyrazole-dione derivatives (6a-6h) against various life stages of Ae. aegypti. Besides, to study the mode of action of the active compound by molecular docking and histopathological analysis. Methods: All derivatives were synthesized from the reaction between 2-hydroxy-1,4-naphthoquinone, chromene-3-carbaldehyde, and 1-phenyl-3-methyl-pyrazol-5-one by using one pot sequential multicomponent reaction. The mosquito life stages were subjected to diverse concentrations ranging from 1.25, 2.5, 5.0, and 10 ppm for lawsone and its derivatives. The structure of all synthesized compounds was characterized by spectroscopic analysis. Docking analysis was performed using autodock tools. Midgut sections of Ae. aegypti larvae were analyzed for histopathological effects. Results: Among the nine compounds screened, derivative 6e showed the highest mortality on Ae. aegypti life stages. The analyzed LC50 and LC90 results of derivative 6e were 3.01, 5.87 ppm, and 3.41, 6.28 ppm on larvae and pupae of Ae. aegypti, respectively. In the ovicidal assay, the derivative 6e recorded 47.2% egg mortality after 96-hour post-exposure to 10 ppm concentration. In molecular docking analysis, the derivative 6e confirmed strong binding interaction (-9.09 kcal/mol and -10.17 kcal/mol) with VAL 60 and HIS 62 of acetylcholinesterase 1 (AChE1) model and LYS 255, LYS 263 of kynurenine aminotransferase of Ae. aegypti, respectively. The histopathological results showed that the derivative 6e affected the columnar epithelial cells (CC) and peritrophic membrane (pM). Conclusion: The derivative 6e is highly effective in the life stages of Ae. aegypti mosquito and it could be used in the integrated mosquito management programme.

Many flaviviruses are remarkable human pathogens that can be transmitted by mosquitoes and ticks. Despite the availability of vaccines for viral infections such as yellow fever, Japanese encephalitis, and tick-borne encephalitis, flavivirus-like dengue is still a significant life-threatening illness worldwide. To date, there is no antiviral treatment for dengue therapy. Industry and the research community have been taking ongoing steps to improve anti-flavivirus treatment to meet this clinical need. The successful activity has been involved in the inhibition of the virus entry fusion process in the last two decades. In this study, the latest understanding of the use of small molecules used as fusion inhibitors has been comprehensively presented. We summarized the structure, the process of fusion of dengue virus E protein (DENV E), and the amino acids involved in the fusion process. Special attention has been given to small molecules that allow conformational changes to DENV E protein, viz. blocking the pocket of βOG, which is important for fusion.

Dengue virus (DENV), chikungunya virus (CHIKV), and Zika virus (ZIKV) are arboviruses that can affect maternal and fetal outcome if acquired during pregnancy. This study was done to estimate the positivity of DENV, CHIKV, and ZIKV in febrile pregnant women attending a tertiary care hospital in north India. Symptomatic pregnant women were tested for these viruses by IgM ELISA and/or by Trioplex real-time polymerase chain reaction. Their symptoms and laboratory parameters were recorded and were followed up till delivery to know their immediate delivery outcome. Of 104 women tested, 50 (48.1%) were positive for viral markers. Of these, evidence of infection by DENV, CHIKV, and both was found in 34 (32.7%), 10 (9.6%), and 6 (5.8%), respectively. ZIKV was not detected in any woman. Maximum DENV positivity occurred in the third trimester of pregnancy and in women residing in urban than rural areas. Chills and rigors, arthralgia, retro-orbital pain, anemia, and vaginal bleeding were more commonly associated with DENV positivity. Backache, arthralgia, jaundice, and vaginal bleeding were more common in CHIKV positives but the difference between positives and nonpositives regarding these symptoms was not statistically significant. Dengue infections were associated with more frequent hospitalizations (OR = 8.38, 95% confidence intervals [CI] = 3.29–21.30) and mortality (OR = 19.0, 95% CI = 1.01–357.10). Hence, to conclude, in India wherever possible, all symptomatic pregnant women should be screened for DENV, CHIKV, and ZIKV as part of sentinel surveillance for ZIKV.

Dengue hemorrhagic fever (DHF) is still a health problem, especially in endemic areas. Aedes aegypti mosquito as a vector for the dengue virus needs serious attention. The 3M Plus Mosquito Nest Eradication has been promoted by the government as a preventive effort to increase the incidence of dengue fever. The purpose of this community service is to increase the knowledge of housewives (IRT) through the implementation of counseling and assistance in making ovitrap with the principle of reuse to reduce the population of Aedes aegypti larvae. This community service was carried out with an intervention approach in a one group pretest-posttest design experimental design. The location of community service is in RW 04, Cisaranteun Endah Village at 199 IRT. Most of the IRT (53.3%) before attending the counseling had less knowledge and after attending the counseling most of the IRT (69.3%) had good knowledge. The average score before counseling was 50.28 with a standard deviation of 15.518 and the average score after counseling was 81.08 with a standard deviation of 10.325, and the p-value was 0.000. This means that there is a significant difference in the level of knowledge of IRT before and after being given counseling and assistance. The goal of community service is to achieve a significant increase in IRT knowledge about ovitrap as a means of controlling the population of Aedes aegyti mosquito larvae, how to make it and provide assistance in making ovitrap with the principle of Re-use.

Dengue is an acute systemic viral disease that has been developed globally in both chronic and epidemic transmission periods. Dengue virus (DENV) is a member of the Flavivirus genus of the Flaviviridae family, which endangers public health. Limited studies have been performed in the Saudi Arabia and there are no epidemiological as well as molecular screening of DENV in the Southwestern region and this current study was conducted on the epidemiology of dengue in the Southwestern region of Saudi Arabia. Simultaneously, we have screened the 100 patients for DENV using the real-time reverse transcriptase polymerase chain reaction (RT-PCR) assay. The current study results confirmed that 6637 people from various hospitals and locations in Jazan, Southwestern regions, were enrolled in this study from 2012 to 2020. The overall mean age was 30.02 ± 18.01 years, with 62.8% of males and 37.2% of females enrolled. This study included nearly three-fourths of the Saudi participants and one-fourth of the expatriates, and 56.6% of the positive cases were enrolled. In 2019, the most instances were enrolled, with 44% of positive cases. When screened using the RT-PCR assay, 93% of the positive patients were recruited, according to the quality control analysis. In conclusion, the current study results confirmed the prevalence of DENV was increased drastically since 2012 to 2020. High number of cases were registered prior to the Pandemic. The screening for DENV was performed with RT-PCR assay and NSI antigen should also be implemented to cross-check the results which was previously performed with RT-PCR analysis.

Background: Dengue is known as the most severe arboviral infection in the world spread by Aedes aegypti. However, conventional and laboratory-based enzyme-linked immunosorbent assays (ELISA) are the current approaches in detecting dengue virus (DENV), requiring skilled and well-trained personnel to operate. Therefore, the ultrasensitive and label-free technique of the Silicon Nanowire (SiNW) biosensor was chosen for rapid detection of DENV. Methods: In this study, a SiNW field-effect transistor (FET) biosensor integrated with a back-gate of the low-doped p-type Silicon-on-insulator (SOI) wafer was fabricated through conventional photolithography and Inductively Coupled Plasma – Reactive Ion Etching (ICP-RIE) for Dengue Virus type-2 (DENV-2) DNA detection. The morphological characteristics of back-gated SiNW-FET were examined using a field-emission scanning electron microscope supported by the elemental analysis via energy-dispersive X-ray spectroscopy. Results and Discussion: A complementary (target) single-stranded deoxyribonucleic acid (ssDNA) was recognized when the target DNA was hybridized with the probe DNA attached to SiNW surfaces. Based on the slope of the linear regression curve, the back-gated SiNW-FET biosensor demonstrated the sensitivity of 3.3 nAM-1 with a detection limit of 10 fM. Furthermore, the drain and back-gate voltages were also found to influence the SiNW conductance changed. Conclusion: Thus, the results obtained suggest that the back-gated SiNW-FET shows good stability in both biosensing applications and medical diagnosis throughout the conventional photolithography method.

Dengue virus poses a serious worldwide health threat with up to 400 million infections occurring annually in over 100 countries. Currently, there are no specific therapeutics available, and the only licensed vaccine encompasses risk of hospitalization in immunologically naive individuals. In the current work for the first time we are reporting dengue virus type 2 (DENV2) inhibitory activity of newly designed 3-chlorobenzyl linked 1,9-diazaspiro[5.5]undecane derivatives. Compounds with substitutions featuring 2-methylbenzyl (SPO-6, EC50 = 11.43 ± 0.87 μM), 4-bromobenzyl (SPO-7, EC50 = 14.15 ± 0.50 µM), and 4-cyanobenzyl (SPO-13, EC50 = 20.77 ± 1.92 µM) groups and Ribavirin (IC50=50.9±18 µM, J. Gen. Virol.2006,87, 1947-1952) were found to be potent against DENV2 in a cell-based assay. Docking calculations identified NS5-methyltransferase as the most probable target for this series of compounds. Molecular dynamics simulations of NS5-methyltransferase reproduced the experimental binding affinity findings by yielding ΔGbind values that predicted SPO-6 to possess the most favorable binding energy of -27.2 ± 3.9 kcal/mol compared to SPO-7, SPO-13, and Ribavirin with -22.5 ± 4.7, -22.5 ± 4.6, and -20.0 ± 4.6 kcal/mol, respectively. In addition, based on Lipinski’s rule of 5 SPO-6 was found to be nontoxic and possessed a better score of drug likeness (5.87) in comparison to the standard drug ribavirin (1.72).

Double filtration plasmapheresis (DFPP) is an apheretic technique that selectively removes high molecular weight substances using a plasma component filter. DFPP has been used to treat positive-sense RNA virus infections, mainly chronic hepatitis C virus (HCV) infection, because of its ability to directly eliminate viral particles from blood plasma from 2008 to about 2015, before direct-acting antiviral agents was marketed. This effect has been termed virus removal and eradication by DFPP. HCV is a positive-sense RNA virus similar to West Nile virus, dengue virus and the SARS and Middle East respiratory syndrome coronaviruses. SARS-CoV-2 is classified same viral species. These viruses are all classified in Family Flaviviridae which are family of single-stranded plus-stranded RNA viruses. Viral particles are 40–60 nm in diameter, enveloped and spherical in shape. We present a rare case of HCV removal where an RNA virus infection that copresented with virus-associated autoimmune hepatitis was eliminated using DFPP. Our results indicate that DFPP may facilitate prompt viraemia reduction and may have novel treatment applications for SARS-CoV-2, that is, use of therapeutic plasma exchange for fulminant COVID-19.

Half of the world's population is at risk of arthropod-borne virus (arbovirus) infections. Several arbovirus infections have been associated with Guillain-Barré syndrome (GBS). We investigated whether arboviruses are driving GBS beyond epidemic phases of transmission and studied the antibody response to glycolipids. The protocol of the International Guillain-Barré syndrome Outcome Study (IGOS), an observational prospective cohort study, was adapted to a case-control design. Serum samples were tested for a recent infection with Zika virus (ZIKV), dengue virus (DENV), chikungunya (CHIKV) virus, hepatitis E virus, Epstein-Barr virus (EBV), cytomegalovirus (CMV), Campylobacter jejuni, and Mycoplasma pneumoniae, and for antibodies to glycolipids. Forty-nine patients were included from Brazil (63%), Argentina (14%), and Malaysia (22%). Evidence of a recent infection was found in 27/49 (55%) patients: C jejuni (n = 15, 31%), M pneumoniae (n = 5, 10%), CHIKV (n = 2, 4%), EBV (n = 1, 2%), C jejuni and M pneumoniae (n = 2, 4%), CMV and DENV (n = 1, 2%), and C jejuni and DENV (n = 1, 2%). In 22 patients, 35 paired controls were collected. Odds ratio for recent infections did not significantly differ between cases and controls. No typical anti-ganglioside antibody binding was associated with recent arbovirus infection. We conclude that arbovirus infections occur in GBS patients outside of epidemic viral transmission, although not significantly more than in controls. Broad infection and anti-ganglioside antibody serology are important to establish the most likely pathogenic trigger in GBS patients. Larger studies are necessary to determine the association between arboviruses and GBS.

Dengue fever is a mosquito-borne viral disease spread in tropical and subtropical regions caused by the dengue virus (DENV). DENV causes a febrile illness, severe forms including hemorrhagic fevers and shock with fatalities in humans. DENV-2 is frequently associated with severe dengue infections and epidemics. DENV-2 strains from Guangdong, China, have not been characterized to compare the phylogenetics and pathogenicity of different DENV-2 subgenotype strains in both vitro and vivo. A total of 22 patients tested to be DENV-2 positive and were enrolled in this study, 22 complete genomes were obtained by virus isolation and high-throughput sequencing. Phylogenetic and single amino polymorphism (SAP) analysis indicated that two major subgenotypes (A and C) of DENV-2 Cosmopolitan were prevalent in Guangdong in 2018. The apparent change of major subgenotypes of DENV-2 circulating in Guangdong indicated the diversity of DENV-2 strains, including endemic genotype and imported genotype. It alerted the risk of cross-border transmission of DENV. A significant difference in replication rate was observed in C6/36 between different DENV-2 strains, although growth kinetics comparison of different DENV-2 Cosmopolitan subgenotypes showed similar profiles. DENV-2 subgenotypes (A and C) replicated efficiently in IFNAR−/− C57BL/6 mice, and subgenotype A of Cosmopolitan infected mice showed increased weight loss and delayed viral clearance compared with the subgenotype C group. DENV-2 prevalent in Guangdong in 2018 showed apparent genetic and pathogenicity diversity in both vitro and vivo, indicating the necessity of molecular surveillance and exploration of the relationship between its pathogenicity and clinical characteristics.

Background. Dengue Hemorrhagic Fever (DHF) is infection caused by Dengue Virus. Failure of vascularization is a main symptom of Dengue Hemorrhagic Fever inducing mediator secretion by an immune cell. Fc g RIIA and CCL2 have a significant role in dengue pathogenesis and possibility in having a chance to cause dengue with a worse manifestation. Objective. A nalysis of bio-informatic structure, function and expression of Fc g RIIA gene . Methods. Insilico analysis used NCBI database to find position and sequences. Analysis mutant use SNO and OMIM. Protein prediction withUniprot. Result. Fc g RIIA human with access number of NM_001136219 by a length of 2429 bp has its full name as Fc Fragment of IgG receptor IIa, located in 1q23.3 chromosom. analyzed mutation was rs1801274 with type of missense protein residue function experiencing a change from Histidin (H) turning into Arginin (R) with allele of wild-type A and becoming G amino acid position of 166 . there was structural difference of Fc g RIIA gene in wild type and mutant . Conclusion. Gene Fc g RIIA is a play a role of pathogenesis of dengue infection. Mutation in Fc g RIIA have polymorfisme at Dengue Hemorrage Fever

Dengue fever is regarded as an important neglected Arboviral disease worldwide. This study aimed at investigating the prevalence of dengue IgM seroprevalence, malaria parasitaemia and some haematological parameters of HIV infected individuals attending Chukwuemeka Odumegwu Ojukwu Teaching Hospital Amaku, Awka, Nigeria. A cross sectional study consisting of 188 participants was performed. The demographic data and possible risks factors of the subjects were obtained using well-structured questionnaire. Dengue virus IgM was analysed using Enzyme-linked immunosorbent assay (ELISA) techniques, Malaria parasitaemia was determined using microscopy technique while some haematological parameters were evaluated using heamatology auto analyser (PE-6800 fully auto heamatology analyser procan). Statistical analysis was performed using the statistical package for social (spss) version 25. The results of this study showed that the prevalence of Dengue virus was 20.2% while that of Malaria was 37.2%. The co-infection of Dengue virus IgM antibodies and Malaria parasitemia was 8.51%. Plasmodium falciparium was seen as the only specie of malaria parasite present in the study. The results of some haematogical parameters of the Dengue virus seropositive participants as compared with the Dengue virus seronegative participants were statistically significant with neutrophils (p = 0.035), mean cell hemoglobin concentration (MCHC = p

Dengue viruses are the most prevalent arthropod-borne viral diseases in humans, infecting 50-100 million people each year. Its serotypes are the most common causes of arboviral illness, putting half of the world's population at risk of infection. Because there is no vaccine or antiviral medicines, the only way to manage the disease is to reduce the Aedes mosquito vectors. DENV infection can be asymptomatic or cause a self-limiting, acute febrile illness with varying degrees of severity. High fever, headache, stomach discomfort, rash, myalgia, and arthralgia are the typical symptoms of dengue fever (DF). Thrombocytopenia, vascular leakage, and hypotension are symptoms of severe dengue, dengue hemorrhagic fever (DHF), and dengue shock syndrome (DSS). Systemic shock characterizes DSS, which can be deadly. Dengue virus infection pathogenesis is linked to a complex interaction between virus, host genes, and host immune response. Major drivers of disease vulnerability include host factors such as antibody-dependent enhancement (ADE), memory cross-reactive T cells, anti-DENV NS1 antibodies, autoimmunity, and genetic variables. The NS1 protein and anti-DENV NS1 antibodies were thought to be involved in the development of severe dengue. The progressive infection may change the cytokine response of cross reactive CD4+ T cells. The need for dengue vaccines that can generate strong protective immunity against all four serotypes is required. To create such vaccines, a thorough understanding of DENV adaptive immunity is required. Structural and functional research have shown that the degree of prM protein cleavage as well as the ensemble of conformational states sampled by virions influence DENV sensitivity to antibody-mediated neutralization, which has crucial implications for vaccine formulation.

Dengue, a rapidly spreading mosquito-borne human viral disease caused by dengue virus (DENV), is a public health concern in tropical and subtropical areas due to its expanding geographical range. DENV can cause a wide spectrum of illnesses in humans, ranging from asymptomatic infection or mild dengue fever (DF) to life-threatening dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). Dengue is caused by four DENV serotypes; however, dengue pathogenesis is complex and poorly understood. Establishing a useful animal model that can exhibit dengue-fever-like signs similar to those in humans is essential to improve our understanding of the host response and pathogenesis of DENV. Although several animal models, including mouse models, non-human primate models, and a recently reported tree shrew model, have been investigated for DENV infection, animal models with clinical signs that are similar to those of DF in humans have not yet been established. Although animal models are essential for understanding the pathogenesis of DENV infection and for drug and vaccine development, each animal model has its own strengths and limitations. Therefore, in this review, we provide a recent overview of animal models for DENV infection and pathogenesis, focusing on studies of the antibody-dependent enhancement (ADE) effect in animal models.

The commitment to replicate the RNA genome of flaviviruses without a primer involves RNA-protein interactions that have been shown to include the recognition of the stem-loop A (SLA) in the 5' untranslated region (UTR) by the nonstructural protein NS5. We show that DENV2 NS5 arginine 888, located within the carboxy-terminal 18 residues, is completely conserved in all flaviviruses and interacts specifically with the top-loop of 3'SL in the 3'UTR which contains the pentanucleotide 5'-CACAG-3' previously shown to be critical for flavivirus RNA replication. We present virological and biochemical data showing the importance of this Arg 888 in virus viability and de novo initiation of RNA polymerase activity in vitro. Based on our binding studies, we hypothesize that ternary complex formation of NS5 with 3'SL, followed by dimerization, leads to the formation of the de novo initiation complex that could be regulated by the reversible zipping and unzipping of cis-acting RNA elements. National Medical Research Council (NMRC) National Research Foundation (NRF) Published version Financial support in part from the National Research Foundation (NRF2016-CRP001-063) and National Medical Research Council of Singapore (NMRC grants MOH-000086: MOH-OFIRG18-may-0006) is gratefully acknowledged.

Background Due to an ageing population, dengue among older patients is encountered more frequently in many countries. Our study aimed to explore the clinico-laboratory parameters and outcomes among dengue-infected older patients in comparison with younger patients. Methods This retrospective chart review involved dengue patients with dengue non-structural protein 1 (NS1) antigen positivity admitted to a tertiary hospital in Malaysia from January to July 2015. A comparison was made between older people (aged ≥60 y) and others. Results Among 406 dengue patients, 43 (10.6%) were older people. Older dengue patients were less likely to present with persistent vomiting (adjusted OR [AOR] 0.247, 95% CI 0.093 to 0.656, p=0.005), while restlessness and confusion were more common at presentation (AOR 3.356, 95% CI 1.024 to 11.003, p=0.046). Older patients had significantly lower albumin upon admission (38 vs 40 g/L, p=0.036) and during hospital stay (35 vs 37 g/L, p=0.015). Compared with younger patients, older patients were more likely to have experienced nadir platelet counts of Conclusions Diagnosis of dengue in older people may be challenging because of atypical presentations. Increased vigilance is necessary as there is an increased tendency to develop severe thrombocytopenia, hypoalbuminemia and prolonged hospitalisation in older people.

Dengue virus (DENV) and chikungunya virus (DENV) are arboviruses of major public health importance. Monitoring circulation of medically important mosquito-borne viruses in the Indo Pacific region allows countries to predict disease outbreaks and prepare mitigation and control strategies. We have monitored long-term molecular epidemiology of DENV and CHIKV in Indonesia and Western Australia (WA), with febrile Western Australian travellers returning from Indonesia as sentinels. Our findings provide insights into the transmission dynamics of CHIKV genotypes and DENV serotypes, genotypes and lineages in the region and virus importation to WA. Our ongoing studies provide valuable and timely information on transmission of emerging and re-emerging arboviruses in the Indo Pacific region and furthermore provide detailed genomic data that inform our understanding of viral and epidemic virulence.

Bioengineered yeast bio-nanomaterials termed nanoyeasts displaying antibody single-chain variable fragments (scFvs) against diagnostic targets are a promising alternative to monoclonal antibodies (mAbs). A potential limitation for translating nanoyeasts into diagnostic tools is batch-to-batch variability. Herein, we demonstrate a systematic approach for cost-efficient production of highly specific nanoyeasts that enabled accurate dengue virus (DENV) detection by immunoassay (2.5% CV). Yeasts bioengineered to surface express DENV-specific scFvs (up to 66% of the total cell population) were fragmented into nanoyeast fractions trialing sonication, bead beating, and high-pressure disruption methods. Nanoyeast fractions from sonication had optimal target binding, uniform particle size (±89 nm), were stable, and retained diagnostic activity for 7 days at 37 °C compared to traditional mAbs that lost activity after 1 day at 37 °C. We engineered a panel of nanoyeast scFvs targeting DENV nonstructural protein 1 (NS1): (i) specific for serotyping DENV 1-4 and (ii) cross-reactive anti-DENV scFvs that are suitable for "yes/no" diagnostic applications. We demonstrate highly specific nanoyeast scFvs for serotyping DENV. We show that nanoyeast scFvs specifically detect NS1 in simulated patient plasma with a limit of detection of 250 ng/mL, the concentration found in infected patients.

Dengue virus (DENV) non-structural protein 5 (NS5) is critical for viral RNA synthesis within endoplasmic reticulum (ER)-derived replication complexes in the cytoplasm; however a proportion of NS5 is known to be localized to the nucleus of infected cells. The importance of nuclear DENV NS5 on viral replication and pathogenesis is still unclear. We recently discovered a nuclear localization signal (NLS) residing in the C-terminal 18 amino acid (Cter18) region of DENV NS5 and that a single NS5 P884T amino acid substitution adjacent to the NLS is sufficient to relocalize a significant proportion of DENV2 NS5 from the nucleus to the cytoplasm of infected cells. Here, in vitro studies show that the DENV2 NS5 P884T mutant replicates similarly to the parental wild-type infectious clone-derived virus while inducing a greater type I interferon and inflammatory cytokine response, in a manner independent of NS5's ability to degrade STAT2 or regulate SAT1 splicing. In both AG129 mouse and Aedes aegypti mosquito infection models, the P884T virus exhibits lower levels of viral replication only at early timepoints. Intriguingly, there appears to be a tendency for selection pressure to revert to the wild-type proline in P884T-infected Ae. aegypti, in agreement with the high conservation of the proline at this position of NS5 in DENV2, 3, and 4. These results suggest that the predominant nuclear localization of DENV NS5, while not required for viral RNA replication, may play a role in pathogenesis and modulation of the host immune response and contribute to viral fitness in the mosquito host.

We performed a 2-year prospective cohort study to determine the incidence of dengue in Angoda, Colombo district, Sri Lanka (NCT02570152). The primary objective was to determine the incidence of acute febrile illness (AFI) because of laboratory confirmed dengue (LCD). Secondary objectives were to determine AFI incidence because of non-LCD, describe AFI symptoms, and estimate AFI incidence because of LCD by dengue virus (DENV)-type and age group. Participants from households with at least one minor and one adult (≤50 years) were enrolled and followed with scheduled weekly visits and, in case of AFI, unscheduled visits. Blood was collected for DENV detection at AFI visits, and symptoms recorded during the 7-day period following AFI onset. A total of 2,004 participants were enrolled (971 children, and 1,033 adults). A total of 55 LCD episodes were detected (overall incidence of 14.2 per 1,000 person-years). Incidence was the highest among children < 5 years (21.3 per 1,000 person-years) and 5–11 years (22.7 per 1,000 person-years), compared with adults ≥ 18 years (9.2 per 1,000 person-years). LCD was mostly (83.6%) caused by DENV-2 (n = 46), followed by DENV-1 (n = 6) and DENV-3 (n = 3). Common symptoms of LCD were headache, fatigue, myalgia, loss of appetite, and arthralgia. Incidence of AFI because of non-LCD was 47.3 per 1,000 person-years. In conclusion, this study reports the LCD incidence for a DENV-2 dominated epidemic that is comparable to the incidence of suspected dengue reported passively for 2017, one of the worst outbreaks in recent history.

Serology-based dengue assays at times produce inaccurate results especially in the early phase of disease onset. A more precise diagnostic approach detecting dengue infections in the early phase enables better management of the disease. This helps reduce dengue-associated morbidity and mortality. Besides, an early diagnosis of dengue is also very beneficial in a dengue outbreak and in endemic regions. In this light, this study aimed to determine the potential of the dengue virus (DENV) non-structural 1 (NS1) gene as an early detection biomarker. The cytopathic effects (CPE) were monitored and the cell death of DENV serotype-2 (DENV2)-infected Vero cells was evaluated for fourteen consecutive days. Only Lemos and in-house NS1-specific primer pairs showed positive amplifications in the preliminary primer validation. Thus, both of the primer pairs were then used to amplify the NS1 gene from the infected cells. The NS1 gene was detected as early as day-2 post-infection using the in-house primers. There was no amplicon produced using the Lemos primers. This is speculated to be attributable to the relatively lower complementarity of the primer sequences with that of the template and low amount of viral mRNA in the DENV2-infected cells. Conclusively, the DENV NS1 gene is a potential early detection marker, however, the NS1-specific primers should be pre-validated to ensure a reliable dengue diagnosis.

Background: Dengue fever (DF) is caused by dengue virus (DENV), a positive-sense single stranded RNA virus of the genus Flavivirus in the family Flaviviridae. The DF has been reported as one of the most important arboviral diseases in many parts of the world including Sudan. DENV is a widely spreading disease that has resulted in an emerging infectious disease world-wide. Aim: The aim of this study was to estimate the prevalence of dengue virus in Red sea state, Sudan. Materials and Methods: This study is a cross sectional study, carried out in Eastern part of Sudan with an impartial method to determine the DENV antibodies status in Red Sea state, Sudan, Dengue Virus (DENV) antibody test was done for each sample. Blood samples were collected from each patient in a plain container, and then serum was separated and tested for (DENV) IgM by using ELISA. Results: Of the total 380 dengue cases tested 106 (27.9%) were identified as anti-dengue IgM positive. 57.1% (n=217) were females and 42.9% (n=163) were males, the highest numbers of cases; 152 (40%) from the age group between 40 years and above and least numbers of cases; 47(12.4%) from the age group of 10-19 years. 55 (14.5%) cases among age groups of less than 10 years, 73 (19.2%) from the age group 20-29 years and six 53 (13.9%) from the age group between 30-39 years of age. Conclusion: We can conclude that serotypes (IgM) of dengue virus prevalence is 27.9% in Red Sea State, Sudan and this finding indicate that the residents of the Red State are at risk of developing the disease. Also, there was significant variation between age and the occurrence of the disease. The Ministry of health should initiate dengue surveillance and commence an integrated vector control programme.

Objective To evaluate the protective effect of house-screening (HS) on indoor Ae. aegypti infestation, abundance and arboviral infection in Merida, Mexico. Methods In 2019, we performed a cluster randomized controlled trial (6 control and 6 intervention areas: 100 households/area). Intervention clusters received permanently fixed fiberglass HS on all windows and doors. The study included two cross-sectional entomologic surveys, one baseline (dry season in May 2019) and one post-intervention (PI, rainy season between September-October 2019). The presence and number of indoor Aedes females and blood-fed females (indoor mosquito infestation) as well as arboviral infections with dengue (DENV) and Zika (ZIKV) viruses were evaluated in a subsample of 30 houses within each cluster. Results HS houses had significatively lower risk for having Aedes aegypti female mosquitoes (odds ratio [OR]=0.56, 95% C. I. 0.33-0.97, P=0.04) and blood-fed females (OR=0.53, 95% C. I. 0.28-0.97, P=0.04) than unscreened households from the control arm. Compared to control houses, HS houses had significantly lower indoor Ae. aegypti abundance (rate ratio [RR]=0.50, 95% C. I. 0.30-0.83, P=0.01), blood-fed Ae. aegypti females (RR=0.48, 95% C. I. 0.27-0.85, P=0.01) and female Ae. aegypti positive for arboviruses (OR=0.29, 95% CI 0.10-0.86, P=0.02). The estimated intervention efficacy in reducing Ae. aegypti arbovirus infection was 71%. Conclusions These results provide evidence supporting the use of HS as an effective pesticide-free method to control house infestations with Aedes aegypti and reduce the transmission of Aedes-transmitted viruses such as DENV, chikungunya (CHIKV), and ZIKV.

In this paper, the mathematical model used is the host-vector model for transmission on of dengue hemorrhagic fever where the host population consists of three compartments, namely susceptible host, infected, and recovered, while the vector population consists of two compartments, namely susceptible vector and infected vector. From this model, an estimate of the basic reproduction number will be constructed with the assumption that the number or humans and mosquitoes infected with the dengue virus grows exponentially with the same growth rate. Applications using field data in the City of Bima obtained an basic reproduction number estimates of . Because the estimated values for the basic reproduction number are greater than one, it illustrates that the spread of dengue hemorrhagic fever in Bima City from 2018 to 2020 is categorized as an epidemic.

Here, we describe the development of the in-house anti-Zika virus (ZIKV) IgM antibody capture ELISA (in-house ZIKV IgM ELISA) for the detection and diagnosis of acute ZIKV infections. We compared the in-house ZIKV IgM ELISA assay performance against two commercial kits, Euroimmun ZIKV IgM and InBios 2.0 ZIKV IgM ELISA. We tested the assays’ ability to detect anti-ZIKV IgM using a well-defined serum sample panel. This panel included 80 ZIKV negative samples (20 negative, 20 found to be primary dengue virus [DENV][ infections, 20 secondary DENV infections, and 20 Japanese encephalitis virus [JEV] infections) and 67 ZIKV reverse transcriptase–polymerase chain reaction–positive acute serum samples. The OD values were calculated to enzyme immunoassay (EIA) unts by comparing them to weak positive controls. The results demonstrated the high sensitivity (88.06%) and specificity (90.00%) of our in-house ZIKV IgM ELISA and its 89.12% overall percentage agreement. The kappa values were deemed to be within excellent range and comparable to the InBios ZIKV IgM ELISA. Some cross-reactivity was observed among secondary DENV and JEV samples, and to a much lower extent, among primary DENV samples. These data indicate that our in-house ZIKV IgM ELISA is a reliable assay for the detection of anti-ZIKV IgM antibodies in serum.

Dengue is a vector-borne viral disease caused by the flavivirus dengue virus (DENV). Approximately 400 million cases and 22 000 deaths occur due to dengue worldwide each year. It has been reported in more than 100 countries in tropical and subtropical regions. A positive-stranded enveloped RNA virus (DENV) is principally transmitted by Aedes mosquitoes. It has four antigenically distinct serotypes, DENV-1 to DENV-4, with different genotypes and three structural proteins and seven non-structural proteins. Clinical symptoms of dengue range from mild fever to severe dengue hemorrhagic fever (DHF) or dengue shock syndrome (DSS), with thrombocytopenia, leucopenia, and increased vascular permeability. Although primary infection causes activation of immune responses against DENV serotypes, the severity of the disease is enhanced via heterotypic infection by various serotypes as well as antibody-dependent enhancement (ADE). The first licensed DENV vaccine was tetravalent CYD Denvaxia, but it has not been approved in all countries. The lack of a suitable animal model, a proper mechanistic study in pathogenesis, and ADE are the main hindrances in vaccine development. This review summarizes the current knowledge on DENV epidemiology, biology, and disease aetiology in the context of prevention and protection from dengue virus disease.

BACKGROUND Platelets are now recognized as immunological sentries in the first line of defense that participate in the detection and response to pathogens. This frequently results in a decrease in the number of circulating platelets. Different mechanisms have been hypothesized to explain the thrombocytopenia in patients with severe dengue, one of them is the participation of the non-structural protein 1 (NS1) of dengue virus (DENV), which can be secreted into circulation during DENV infection and promotes a more efficient infection. OBJECTIVE The present study aimed to investigate the ability of platelet response to stimulation with full-length DENV NS1 protein and its domains. METHODS DENV NS1 plasmid was transfected into HEK-293T. Proteins were purified by Niquel Sepharose affinity chromatography. Secreted proteins were assessed by sodium dodecylsulfate polyacrylamide gel electrophoresis, Coomassie staining and western blot. Platelet-rich plasma was directly incubated with DENV NS1 proteins. Platelet activation was confirmed by expression of αIIbβIII and P-selectin by flow cytometry. Platelet aggregation was also assessed using DENV NS1 protein and its individual domains as agonists. RESULTS DENV NS1 protein and its domains induce P-selectin and αIIbβ3 complex expression on platelet surfaces. DENV NS1 induce a stable platelet aggregation after the addition of a minimal dose of adenosine diphosphate (ADP), epinephrine (EPI), or collagen. Interestingly, only EPI could induce the formation of platelet aggregates after incubation with the protein domains of NS1. CONCLUSION Our results suggest that the full DENV NS1 protein and also its domains promote platelet recognition, activation, and aggregation.

Background Sugar feeding is a fundamental behaviour of many mosquito species. For Aedes albopictus, an important vector of dengue virus and chikungunya virus, little is known about its sugar-feeding behaviour, and no studies have been conducted on this in the southern hemisphere. This knowledge is pivotal for determining the potential of attractive targeted sugar baits (ATSBs) to control this important vector. Methods The prevalence of sugar was assessed in 1808 Ae. albopictus from Masig Island, Torres Strait, Australia collected between 13 and 25 March 2020. Fructose presence and content in field-collected Ae. albopictus were quantified using the cold anthrone assay. Results Significantly more male (35.8%) than female (28.4%) Ae. albopictus were sugar fed. There was a significant interaction between sex and time of day on the probability of capturing sugar-fed Ae. albopictus. For both sexes, fructose prevalence and content were higher in mosquitoes caught in the morning than in the afternoon. Female Ae. albopictus collected in the residential habitat were significantly more likely to be sugar fed than those collected in the woodland habitat. Conclusions These findings provide baseline information about the sugar-feeding patterns of Ae. albopictus and provide essential information to enable an assessment of the potential of ATSBs for vector suppression and control on Masig Island, with relevance to other locations where this species occurs. Graphical abstract

Dengue virus and Chikungunya virus are arboviruses that affect thousands of people worldwide annually. The mechanisms involved in viral pathogenesis still need to be better understood. Single nucleotide polymorphisms (SNPs) in immune genes may be involved in the protection, susceptibility, and/or progression of these diseases. This study was performed to investigate the SNP -174 G/C in the interleukin-6 (IL-6) gene in patients with dengue or chikungunya from Northeastern Brazil. A total of 581 blood samples were analyzed, of which 244 were part of the negative control group, genomic DNA was extracted, and the SNP was genotyped using real-time polymerase chain reaction (PCR). The data obtained were used to conduct statistical analyses of the genotype and allele frequencies. We suggest that the G/C genotype and C allele of the SNP -174 G/C in the IL-6 gene are related to protection against dengue in the studied population. No significant differences were observed in chikungunya patients. This is the first study that assessed the association of the SNP -174 G/C in patients with chikungunya. We identified the presence of the C allele as a protective factor against dengue in the studied population.

Objectives A retrospective study was undertaken to investigate the circulating dengue virus (DENV) serotypes and genotypes in India in 2018. Methods In total, 4963 samples referred to virus research diagnostic laboratories (n=21), the Indian Council of Medical Research-National Institute of Virology (ICMR-NIV) and ICMR-NIV field units (n=2) for diagnosis of dengue in 2018 were tested using a real-time reverse transcription polymerase chain reaction assay for the presence of DENV serotypes. Representative samples were sequenced for the envelope (E) gene. Results Regional diversity was observed with regard to the dominant circulating serotypes. DENV-2 was found to be the most common serotype in many states. Thrombocytopenia, petechiae and malaise were associated with DENV-2 infection. Phylogenetic analyses of DENV E gene sequences revealed the circulation of genotypes I and V of DENV-1, two lineages of DENV-2 genotype IV, DENV-3 genotype III and DENV-4 genotype I. Conclusions This study found regional differences in the prevalence of circulating DENV serotypes in India, and provides baseline data for continuous molecular surveillance. Molecular surveillance may have implications for predicting large-scale outbreaks of dengue if regional shifts in the predominantly circulating serotypes and genotypes are detected during the early phase of the dengue season.

Dengue poses a global health threat, which will persist without therapeutic intervention. Immunity induced by exposure to one serotype does not confer long-term protection against secondary infection with other serotypes and is potentially capable of enhancing this infection. Although vaccination is believed to induce durable and protective responses against all the dengue virus (DENV) serotypes in order to reduce the burden posed by this virus, the development of a safe and efficacious vaccine remains a challenge. Immunoinformatics and computational vaccinology have been utilized in studies of infectious diseases to provide insight into the host–pathogen interactions thus justifying their use in vaccine development. Since vaccination is the best bet to reduce the burden posed by DENV, this study is aimed at developing a multi-epitope based vaccines for dengue control. Combined approaches of reverse vaccinology and immunoinformatics were utilized to design multi-epitope based vaccine from the sequence of DENV. Specifically, BCPreds and IEDB servers were used to predict the B-cell and T-cell epitopes, respectively. Molecular docking was carried out using Schrödinger, PATCHDOCK and FIREDOCK. Codon optimization and in silico cloning were done using JCAT and SnapGene respectively. Finally, the efficiency and stability of the designed vaccines were assessed by an in silico immune simulation and molecular dynamic simulation, respectively. The predicted epitopes were prioritized using in-house criteria. Four candidate vaccines (DV-1–4) were designed using suitable adjuvant and linkers in addition to the shortlisted epitopes. The binding interactions of these vaccines against the receptors TLR-2, TLR-4, MHC-1 and MHC-2 show that these candidate vaccines perfectly fit into the binding domains of the receptors. In addition, DV-1 has a better binding energies of − 60.07, − 63.40, − 69.89 kcal/mol against MHC-1, TLR-2, and TLR-4, with respect to the other vaccines. All the designed vaccines were highly antigenic, soluble, non-allergenic, non-toxic, flexible, and topologically assessable. The immune simulation analysis showed that DV-1 may elicit specific immune response against dengue virus. Moreover, codon optimization and in silico cloning validated the expressions of all the designed vaccines in E. coli. Finally, the molecular dynamic study shows that DV-1 is stable with minimum RMSF against TLR4. Immunoinformatics tools are now applied to screen genomes of interest for possible vaccine target. The designed vaccine candidates may be further experimentally investigated as potential vaccines capable of providing definitive preventive measure against dengue virus infection.

Introduction Flaviviruses are a genus of enveloped single-stranded RNA viruses that include dengue virus (DENV), yellow fever virus, West Nile virus (WNV), Japanese encephalitis virus, and Zika virus. Nowadays, diverse serological assays are available to diagnose flaviviruses. However, infection with flaviviruses induces cross-reactive antibodies, which are a challenge for serological diagnosis. Objective This systematic review aimed to assess the magnitude of medically important mosquito-borne flavivirus-induced antibody cross-reactivity and its influence on serological test outcomes. Methods This study was designed based on the PRISMA guidelines. It includes original research articles published between 1994 and 2019 that reported serological cross-reactions between medically important mosquito-borne flaviviruses. Articles were searched on PubMed using controlled vocabulary. Eligibility was assessed by title, abstract, and finally by reading the full paper. The articles included are compared, evaluated, and summarized narratively. Results A total of 2,911 articles were identified, and finally 14 were included. About 15.4%-84% of antibodies produced against non-DENV flaviviruses were cross-reactive with DENV on different assays. Up to 30% IgM and up to 60% IgG antibodies produced against non-WNV flaviviruses were cross-reactive with WNV on EIA assays. The magnitude of antibodies produced against flaviviruses that are cross-reactive with chikungunya virus (Alphavirus) was minimal (only about 7%). The highest antibody cross-reactivity of flaviviruses was reported in IgG-based assays compared to IgM-based assays and assays based on E-specific immunoglobulin compared to NS1-specific immunoglobulin. It was found that preexisting immunity due to vaccination or prior flavivirus exposure to antigenetically related species enhanced the cross-reactive antibody titer. Conclusion This review found the highest cross-reaction between DENV and non-DENV flaviviruses, especially yellow fever virus, and the least between chikungunya virus and DENV. Moreover, cross-reaction was higher on IgG assays than IgM ones and assays based on Eprotein compared to NS1protein. This implies that the reliability of serological test results in areas where more than one flavivirus exists is questionable. Therefore, interpretation of the existing serological assays should be undertaken with a great caution. Furthermore, research on novel diagnostic signatures for differential diagnosis of flaviviruses is needed.

Demam berdarah adalah penyakit yang disebabkan virus dengue yang dibawa nyamuk A. aegypti. Pembuatan Larvasida alami dari tumbuhan seperti Alium sativum L. dan Uncaria acida Roxb sangat diperlukan. Penelitian ini bertujuan untuk membuat larvasida alami dari A. sativum dan U. acida. Penelitian ini merupakan penelitian eksperimental menggunakan Rancangan Acak Lengkap (RAL) untuk melihat efektivitas dari ekstrak A. sativum dengan U. acida sebagai larvasida nyamuk A. aegypti. Penelitian ini menggunakan larva nyamuk sebanyak 20 ekor untuk setiap konsentrasi dan diulang sebanyak 4 kali pengulangan. Hasil penelitian menunjukkan larvasida A. sativum pada konsentrasi tertinggi mencapai 100 % kematian sedangkan larvasida U. acida pada konsentrasi tertinggi mencapai 80% kematian larva nyamuk A. aegypti. Analisa data penelitian diolah menggunakan SPSS versi 20. Analisa One Way Anova ekstrak A. sativum bernilai sig 0.049 dan ekstrak U. acida bernilai sig 0.245. Pada ekstrak A. sativum terdapat perbedaan signifikan kematian larva nyamuk pada setiap konsentrasi sedangkan ekstrak U. acida tidak terdapat perbedaan signifikan kematian larva nyamuk pada setiap pemberian konsentrasi. Analisa T-tes ekstrak A. sativum dan U. acida bernilai sig 0.80 maka tidak ada perbedaan efektivitas di kedua ekstrak larvasida. Dapat disimpulkan hasil penelitian larvasida ekstrak A. sativum dan ekstrak U. acida sama-sama efektif pada larva A. aegypti. Kata kunci : A. aegypti, A. sativum, U. acida, Larvasida, One Way Anova

To date, there are no broad-spectrum antivirals available to treat infections with flaviviruses such as dengue (DENV) and Zika virus (ZIKV). In this study, we determine the broad antiviral activity of the lantibiotic Labyrinthopeptin A1. We show that Laby A1 inhibits all DENV serotypes and various ZIKV strains with IC50 around 1 μM. The structurally related Laby A2 also displayed a consistent, but about tenfold lower, antiviral activity. Furthermore, Laby A1 inhibits many viruses from divergent families such as HIV, YFV, RSV and Punta Torovirus. Of interest, Laby A1 does not show activity against non-enveloped viruses. Its antiviral activity is independent of the cell line or the used evaluation method, and can also be observed in MDDC, a physiologically relevant primary cell type. Furthermore, Laby A1 demonstrates low cellular toxicity and has a more favorable SI compared to duramycin, a well-described lantibiotic with broad-spectrum antiviral activity. Time-of-drug addition experiments demonstrate that Laby A1 inhibits infection and entry processes of ZIKV and DENV. We reveal that Laby A1 performs its broad antiviral activity by interacting with a viral factor rather than a cellular factor, and that it has virucidal properties. Finally, using SPR interaction studies we demonstrate that Laby A1 interacts with several phospholipids (i.e. PE and PS) present in the viral envelope. Together with other recent Labyrinthopeptin antiviral publications, this work validates the activity of Laby A1 as broad antiviral entry inhibitor with a unique mechanism of action and demonstrates its potential value as antiviral agent against emerging flaviviruses. ispartof: VIROLOGY vol:562 pages:74-86 ispartof: location:United States status: published

Background Mosquito-borne dengue virus (DENV) causes major disease worldwide, impacting 50–100 million people every year, and is spread by the major mosquito vector Aedes aegypti. Understanding mosquito physiology, including antiviral mechanisms, and developing new control strategies have become an important step towards the elimination of DENV disease. In the study reported here, we focused on autophagy, a pathway suggested as having a positive influence on virus replication in humans, as a potential antiviral target in the mosquito. Methods To understand the role played by autophagy in Ae. aegypti, we examined the activation of this pathway in Aag-2 cells, an Ae. aegypti-derived cell line, infected with DENV. Rapamycin and 3-methyladenine, two small molecules that have been shown to affect the function of the autophagy pathway, were used to activate or suppress, respectively, the autophagy pathway. Results At 1-day post-DENV infection in Aag-2 cells, transcript levels of both the microtubule-associated protein light chain 3-phosphatidylethanolamine conjugate (LC3-II) and autophagy-related protein 1 (ATG1) increased. Rapamycin treatment activated the autophagy pathway as early as 1-h post-treatment, and the virus titer had decreased in the Aag-2 cells at 2 days post-infection; in contrast, the 3-methyladenine treatment did not significantly affect the DENV titer. Treatment with these small molecules also impacted the ATG12 transcript levels in DENV-infected cells. Conclusions Our studies revealed that activation of the autophagy pathway through rapamycin treatment altered DENV infection in the mosquito cells, suggesting that this pathway could be a possible antiviral mechanism in the mosquito system. Here we provide fundamental information needed to proceed with future experiments and to improve our understanding of the mosquito’s immune response against DENV. Graphical Abstract

During the 2017 outbreak of severe dengue in Sri Lanka, dengue virus (DENV) serotypes 2, 3, and 4 were found to be co-circulating. Our previous study of 295 patients from the National Hospital Kandy in Sri Lanka between March 2017 and January 2018 determined that the dominant infecting serotype was DENV-2. In this study, we aimed to characterize the DENV-3 strains from non-severe and severe dengue patients from our previous study population. Patients’ clinical records and previous laboratory tests, including dengue-specific nonstructural protein 1 antigen rapid test and IgM-capture and IgG enzyme-linked immunosorbent assays, were analyzed together with the present results of real-time reverse transcription polymerase chain reaction and next-generation sequencing of DENV-3. Complete genome analysis determined that DENV-3 isolates belonged to 2 different clades of genotype I and were genetically close to strains from Indonesia, China, Singapore, Malaysia, and Australia. There were 16 amino acid changes among DENV-3 isolates, and a greater number of changes were found in nonstructural proteins than in structural proteins. The emergence of DENV-3 genotype I was noted for the first time in Sri Lanka. Continuous monitoring of this newly emerged genotype and other DENV serotypes and genotypes is needed to determine their effects on future outbreaks and understand the molecular epidemiology of dengue., Japanese Journal of Infectious Diseases, 74(5), pp. 443-449; 2021

Purpose: The interpretation & correlation of the different laboratory parameters in positive dengue cases in order to eval- uate that which laboratory test is more significant for diagnosis of Dengue. Methods: Prospective examination of samples (patients’ serum) for dengue virus of different genotype by using multiplex anti-dengue IgM, IgG. We have done NS-1 test by (ICT) immunochromatographic devices, and complete blood picture (CBC) by Sysmex XP-100. Result: Detection of Viral RNA in 100 patients showed effects in the total of 73 (73.0%) samples. This graphical compar- ison shows the whole positive cases including dengue NS-I antigen, dengue serology (IgM & IgG), total 62 positive cases of NS-I are detected, 10 positive cases of dengue IgM and 9 positive cases of IgG detected, in which Complete Blood Test (CBC) shows remarkable reduction in Platelets (32 cases) and Leucopenia in (24 positive cases). Conclusion: In this research, it is concluded that the diagnosis of dengue cases is preliminary limited to initial stages i.e. CBC or sometimes dengue NS-I, as dengue IgM severity is more effective than that of Dengue NS-I & IgG. Many patients who had negative results in CBC and NS-1 testing, became positive when IgM and IgG serology testing has been done. Keywords: Dengue; NS-1; IgG; IgM; Immunochrometographic test.

Severe dengue virus infection often causes proteinuria through several mechanisms, such as leakage of plasma proteins caused by higher protein filtering in the kidneys. The condition of proteinuria in patients with dengue shock syndrome will affect the management, prognosis, and mortality of patients with dengue virus infection. The objectives of this study were to determine the presence of protein in urine samples in patients in which IgG/IgM dengue was detected, to determine the presence of protein in urine samples in patients without dengue infection, and to determine the relationship between proteinuria in dengue patients and the degree of disease severity. The study was conducted in March-June 2020 at the Clinical Laboratory and Inpatient Clinic of Vita Medika Kepung, Kediri Regency. The method used was the consecutive sampling technique. The minimum sample size was 100 respondents with criteria for suspected dengue infection, onset fever > 4 days, age > 2 years, and no indication of other infectious diseases (blood and urine), divided into two groups, group with positive dengue infection and non-dengue group. The results showed that proteinuria was detected in 26% of respondents, secondary dengue infection and positive serological test of IgG, IgM only IgG were detected in 24 (92.3%) respondents and positive IgG and IgM were found in 2 (7.7%) respondents, this was shown by the p-value = 0.000 in the Chi-Square test with a Prevalence Ratio (PR) value of 11,987. In addition, Chi-Square test results indicated that a higher urine protein/albumin led to more severe disease, with p-value = 0.012 and 0.025 (p

Mosquito Ae. aegypti is the main dengue virus vector which causes the virus to grow and develop properly. The Artificial Membrane Feeding (AMF) method is a method of indirectly transmitting the dengue virus in the Ae. aegypti. This method uses blood feed with EDTA anticoagulant and DEN-3 virus in the insectarium. One way to detect the dengue virus found in Ae mosquito cells. aegypti is an immunohistochemical Streptavidin Biotin Peroxidase Complex (SBPC). In this method, the morphological picture of DEN-3 virus infection cells will be seen through the heparin anticoagulant blood feed using the AMF method. Anticoagulants function to slow the blood clotting to feed the Ae mosquitoes. Aegypti. The aim of this study was to determine the Positive Infection Rate of DEN-3 virus and the morphological picture of DEN-3 virus infection cells using the AMF method of EDTA anticoagulant blood feed through SBPC immunocytochemical examination of Ae mosquitoes. aegypti. The design method of this study was experimental, infected Ae.aegypti mosquitoes using anticoagulant blood containing DEN-3 virus orally as an infectious sample. Negative control used Culex Sp mosquitoes and positive control used adult Ae.aegypti mosquitoes which were infected with DEN-3 virus by injection. Detection of DEN-3 virus in Ae.aegypti mosquitoes through SBPC immunositochemical examination. Results of Positive Infection Rate for Ae.aegypti mosquitoes with EDTA anticoagulant as much as 23.20% through SBPC immunocytochemical examination with a picture of cell morphology of DEN-3 virus infection. The conclusion of SBPC immunositochemical examination showed positive cell morphology of DEN-3 virus infection with EDTA anticoagulant in Ae.aegypti mosquitoes fed by human blood orally through the AMF method.

Serotype 2 of dengue virus (DENV-2) is the most prevalent cause of dengue fevers. In this study, the C-prM gene was used for specific detection of DENV-2 by RT-LAMP assay. The RT-LAMP assay was optimized using the Taguchi design of experiments. The efficiency of the assay in such optimal conditions resulted in 100% sensitivity, 100% specificity, and 100% overall accuracy for detection of 4 copies/μL of the genome of DENV-2. In addition, the detection of 2 copies/μL of the genome of DENV-2 was feasible, although the sensitivity was 50%. Considering the importance of the specific detection of the dengue virus serotypes, the cost-effective RT-LAMP approach can be used for rapid, specific, and sensitive detection of DENV-2. RT-LAMP, as a cost-effective method, was optimized using Taguchi array approach for specific and rapid detection of DENV-2. Such methods can facilitate the diagnosis procedure in remote regions.

BackgroundMost regions in Indonesia experience annual dengue epidemics. However, the province of East Nusa Tenggara has consistently reported low incidence. We conducted a dengue molecular epidemiology study in Kupang, the capital of the province.MethodsDengue patients were recruited from May 2016 to September 2017. Dengue virus (DENV) screening was performed using NS1 and immunoglobulin G (IgG)/IgM detection. Serotype was determined using reverse transcription polymerase chain reaction and the envelope genes were sequenced to infer the genetic identity and phylogeny.ResultsFrom 119 patients, dengue was confirmed in 62 (52%). Compared with official data, underreporting of dengue incidence was observed. The majority (36%) of patients were children ConclusionsThe low dengue incidence was most likely caused by sustained local circulation of endemic viruses. This study provides information on the epidemiology of dengue in a low-endemicity setting that should help future mitigation and disease management.

Dengue hemorrhagic fever (DHF) is a dengue virus infection transmitted by Aedes spp. Climate has a profound influence on mosquito breeding. Palembang has the highest rate of DHF in South Sumatra. This study aimed to investigate the relationship between the components of climate factors and the incidence of DHF in Palembang. This study was cross-sectional, with an observational analytic approach. The Palembang City Health Office compiled data on DHF incidence rates from 2016 to 2020. Climatic factor data (rainfall, number of rainy days, temperature, humidity, wind speed, sun irradiance) were collected from the Climatology Station Class I Palembang - BMKG Station and Task Force that same year. The Spearman test was used to conduct the correlation test. Between 2016 and 2020, there were 3,398 DHF patients. From January to May, DHF increased. There was a significant correlation between rainfall (r = 0.320; p = 0.005), number of rainy days (r = 0.295; p = 0.020), temperature (r = 0.371; p = 0.040), and humidity (r = 0.221; p = 0.024), wind speed (r= 0.76; p = 0.492), and sunlight (r = 0.008; p = 0.865). Rainfall, the number of rainy days, and temperature were three climatic factors determining the increase in dengue incidence in Palembang.

Introduction: Dengue is an endemic arboviral illness. With the increasing incidence of dengue infection, an early diagnostic confirmation of dengue infection in patients facilitates timely clinical intervention, etiological investigation, and disease control. Objective of this study was to evaluate a commercially available serological test kit - Dengue Day 1 Test. This is for the detection of dengue NS1 antigen, differential detection of IgM and IgG antibodies on a single acute serum sample. Materials and Methods: A total of 100 patients with acute febrile illness were included in this study. Serum samples were analysed for Dengue NS1 Ag, IgM & IgG Antibodies using a commercially available Dengue Day 1 Test, rapid solid phase immuno-chromatographic test. Results: As many as 23 (23%) samples were NS1 positive and 17 (17%) samples were positive for IgM antibodies. Based on the combination of dengue NS1 antigen and IgM antibody test, total of 34 patients (34%) were positive for dengue virus infection. Conclusion: Results of the study suggested that a combination of dengue NS1 antigen and IgM antibody tests would increase the rate of detection of dengue illness. This combination would increase the efficacy and aid in early diagnosis of dengue infection. Keywords: Dengue, NS1 antigen, IgM antibodies, Rapid test.

Dengue virus infection is becoming a major public health problem in recent decades because of the mortality and morbidity associated with it. Dengue is endemic in many parts of India and epidemics are frequently reported from various parts of India and abroad. The mortality rate in patients with dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS) is as high as 44%. Hence early and rapid laboratory diagnosis of dengue is crucial. Appropriate clinical management can save the lives of DHF and DSS patients and mortality can be reduced to less than 1%. It is also worthwhile for planning appropriate control strategies. The present communication reports the seroprevalence of dengue infections occurred in Central India.To detect Dengue infection by NS1 Antigen Rapid detection and by IgM ELISA and compare Rapid NS1 Antigen detection test and IgM ELISA test.Blood samples from 5273 suspected cases were collected from January 2016 to December 2016. Sera were separated and subjected for NS1 antigen detection testing by the solid phase immunochromatographic assay, a commercial dengue virus rapid test kit. and antidengue IgM antibody ELISA in the Department of Microbiology, VIMS, Ballari. All samples were put for ELISA.3036 samples were tested for NS1 Antigen detection rapid method.2272 samples were tested for both rapid test and ELISA. Out of 5273 cases, 446 (8.46%) were found to be positive by IgM ELISA. 3036 samples WHICH were tested for NS1 Antigen detection by rapid method 208 (6.85%)samples were positive. The most affected age group was 5-10yrs with 284 cases, out of which 29 were positive, followed by the age group 0f 15yrs and above with 8.74%. Males were affected more than females with a percentage of 9.2 and 7.4 respectively. The highest number of suspected dengue patients admitted was in the month of November, i.e., 459 with 68 positive (14.81%) followed by August (12.16%) and September (11.03%), i.e., 28 with 7 (25%) positive. For the 2272 samples for which both tests were done, 153 cases were positive for rapid test and 137 cases were positive by ELISA. Dengue cases were more during September to November in the post monsoon season which is useful to plan special preventive strategies. The study draws attention toward the male, young and adult age group. To conclude, in countries lacking infrastructure for the diagnostic labs especially in the rural and remote areas, the rapid dengue ICT tests can play a major role in diagnosis and in patient management of acute dengue infection. The rapid ICTs are very simple, easy to perform, and can be used as point of care tests. We suggest that the rapid ICT for NS1 Ag detection may be used in patients presenting with fever less than 5 days