Dengue Serotype Differences  in  Urban and Semi-rural Communities in Ecuador

Dengue is a major vector-borne infection causing large outbreaks in urban communities in tropical regions. During the period 2010- 2014; 434 serum samples from febrile patients were collected from a semi-rural community hospital located in the norwestern region of Ecuador. Dengue virus (DENV) was investigated by reverse transcriptase PCR; a total of 48 samples were positive for dengue. During our study we detected DENV-2 and DENV-3 from 2010 to 2013 and the four DENV serotypes during the period 2013-2014. Surprisingly, our results contrasted with surveys carried out in urban centers throughout the Ecuadorian Coast in which DENV-1, DENV-2 and DENV-4 were prevalent during years 2010-2013 and only 2 serotypes (DENV-1 and DENV-2) in 2014.These results suggest that dengue viruses in semi-rural communities didn’t originate in the Ecuadorian cities.

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Dengue Virus and the Relationship with MicroRNAs

Dengue Fever in a One Health Perspective ◽

10.5772/intechopen.92453 ◽

2020 ◽

Author(s):

Samir Casseb ◽

Karla de Melo

Keyword(s):

Dengue Virus ◽

Viral Infection ◽

Viral Infections ◽

Immune Defense ◽

Tropical Regions ◽

Denv Serotypes ◽

History Of ◽

Infection Processes ◽

The Relationship

Dengue is an acute febrile disease caused by a virus of the genus Flavivirus, family Flaviviridae, endemic in tropical regions of the globe. The agent is a virus with single-stranded RNA, classified into four distinct dengue virus (DENV) serotypes: DENV-1, DENV-2, DENV-3, and DENV-4. The host’s innate and adaptive immune responses play an essential role in determining the natural history of viral infections, especially in dengue. In this context, it has observed in recent years that the presence of RNA interference (RNAi) in viral infection processes is increasing, as well as immune defense. The context microRNAs (miRNAs) go for stood out, as their presence during viral infection, both in the replication of the virus and in the defense against these infections, becomes increasingly noticeable, therefore, making it increasingly necessary to better understand the role of these small RNAs within viral infection by DENV and what their consequences are in aggravating the consequences of patients affected by this disease.

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A tetravalent live attenuated dengue virus vaccine stimulates balanced immunity to multiple serotypes in humans

Nature Communications ◽

10.1038/s41467-021-21384-0 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Usha K. Nivarthi ◽

Jesica Swanstrom ◽

Matthew J. Delacruz ◽

Bhumi Patel ◽

Anna P. Durbin ◽

...

Keyword(s):

Clinical Trials ◽

Dengue Virus ◽

Vaccine Development ◽

Severe Disease ◽

Neutralizing Antibody ◽

Post Challenge ◽

Serum Samples ◽

Denv Serotypes ◽

Vaccine Component ◽

Sterilizing Immunity

AbstractThe four-dengue virus (DENV) serotypes infect several hundred million people annually. For the greatest safety and efficacy, tetravalent DENV vaccines are designed to stimulate balanced protective immunity to all four serotypes. However, this has been difficult to achieve. Clinical trials with a leading vaccine demonstrated that unbalanced replication and immunodominance of one vaccine component over others can lead to low efficacy and vaccine enhanced severe disease. The Laboratory of Infectious Diseases at the National Institutes of Health has developed a live attenuated tetravalent DENV vaccine (TV003), which is currently being tested in phase 3 clinical trials. Here we report, our study to determine if TV003 stimulate balanced and serotype-specific (TS) neutralizing antibody (nAb) responses to each serotype. Serum samples from twenty-one dengue-naive individuals participated under study protocol CIR287 (ClinicalTrials.gov NCT02021968) are analyzed 6 months after vaccination. Most subjects (76%) develop TS nAbs to 3 or 4 DENV serotypes, indicating immunity is induced by each vaccine component. Vaccine-induced TS nAbs map to epitopes known to be targets of nAbs in people infected with wild type DENVs. Following challenge with a partially attenuated strain of DENV2, all 21 subjects are protected from the efficacy endpoints. However, some vaccinated individuals develop post challenge nAb boost, while others mount post-challenge antibody responses that are consistent with sterilizing immunity. TV003 vaccine induced DENV2 TS nAbs are associated with sterilizing immunity. Our results indicate that nAbs to TS epitopes on each serotype may be a better correlate than total levels of nAbs currently used for guiding DENV vaccine development.

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Development of an Enzyme-Linked Immunosorbent Assay for Rapid Detection of Dengue Virus (DENV) NS1 and Differentiation of DENV Serotypes during Early Infection

Journal of Clinical Microbiology ◽

10.1128/jcm.00221-19 ◽

2019 ◽

Vol 57 (7) ◽

Cited By ~ 4

Author(s):

Szu-Chia Lai ◽

Yu-Yine Huang ◽

Pei-Yun Shu ◽

Shu-Fen Chang ◽

Po-Shiuan Hsieh ◽

...

Keyword(s):

Early Diagnosis ◽

Dengue Virus ◽

Immunosorbent Assay ◽

Rapid Detection ◽

Denv Infection ◽

Cross Reactivity ◽

Enzyme Linked Immunosorbent Assay ◽

Serum Samples ◽

Dengue Disease ◽

Denv Serotypes

ABSTRACTDengue fever, caused by infections with the dengue virus (DENV), affects nearly 400 million people globally every year. Early diagnosis and management can reduce the morbidity and mortality rates of severe forms of dengue disease as well as decrease the risk of wider outbreaks. Although the early diagnosis of dengue can be achieved using a number of commercial NS1 detection kits, none of these can differentiate among the four dengue virus serotypes. In this study, we developed an enzyme-linked immunosorbent assay (ELISA) for the detection of dengue virus (DENV) NS1 by pairing a serotype-cross-reactive monoclonal antibody (MAb) with one of four serotype-specific MAbs in order to facilitate the rapid detection of NS1 antigens and the simultaneous differentiation of DENV serotypes. A total of 146 serum samples obtained from patients suspected to be in the acute phase of DENV infection were used to evaluate the clinical application of our novel test for the detection and serotyping of DENV. The overall sensitivity rate of our test was 84.85%, and the sensitivity rates for serotyping were as follows: 88.2% (15/17) for DENV serotype 1 (DENV1), 94.7% (18/19) for DENV2, 75% (12/16) for DENV3, and 66.6% (6/9) for DENV4. Moreover, there was no cross-reactivity among serotypes, and no cross-reactivity was observed in sera from nondengue patients. Thus, our test not only enables the rapid detection of the dengue virus but also can distinguish among the specific serotypes during the early stages of infection. These results indicate that our ELISA for DENV NS1 is a convenient tool that may help elucidate the epidemiology of DENV outbreaks and facilitate the clinical management of DENV infections.

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Prevalence of Hypertension in Akwa Ibom State, South-South Nigeria: Rural versus Urban Communities Study

International Journal of Hypertension ◽

10.1155/2015/975819 ◽

2015 ◽

Vol 2015 ◽

pp. 1-5 ◽

Cited By ~ 6

Author(s):

Effiong Ekong Akpan ◽

Udeme E. Ekrikpo ◽

Aniema I. A. Udo ◽

Bassey Edet Bassey

Keyword(s):

Rural Communities ◽

Urban Communities ◽

Rural Areas ◽

Cross Sectional Study ◽

Joint National Committee ◽

National Committee ◽

Urban Centers ◽

Cross Sectional ◽

Arterial Blood ◽

Seventh Report

Recent studies have shown an increasing trend in the prevalence of hypertension in rural communities compared to that of the urban communities. This study was therefore carried out to determine the prevalence of hypertension and its predictors (if any) in both urban and rural communities of Akwa Ibom State of Nigeria.Subjects and Method. This was a cross-sectional study of urban and rural communities of Akwa Ibom State for the prevalence of hypertension and its predictors. Two urban cities and two rural communities were randomly selected from the three senatorial districts of the state. Hypertension was defined based on the Seventh Report of the Joint National Committee on the Prevention, Detection, Evaluation, and Treatment of Hypertension.Results. Nine hundred and seventy-eight (978) participants were recruited from rural areas and five hundred and ninety (590) from urban centers. The rural populace had higher systolic, diastolic, and mean arterial blood pressure than the urban populace (P<0.001, < 0.002, < 0.001, resp.). The prevalence of hypertension was significantly higher in the rural populace than in the urban populace [44.3% (95% CI 41.1–47.4%) versus 28.6% (95% CI 24.9–32.3%)]. Age, BMI, and proteinuria were independent predictors of hypertension occurrence.Conclusion. There is an epidemiologic change in the prevalence of hypertension in the rural communities of Nigeria.

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Emergence of a Novel Dengue Virus 3 (DENV-3) Genotype-I Coincident with Increased DENV-3 Cases in Yangon, Myanmar between 2017 and 2019

Viruses ◽

10.3390/v13061152 ◽

2021 ◽

Vol 13 (6) ◽

pp. 1152

Author(s):

Aung Min Soe ◽

Mya Myat Ngwe Tun ◽

Takeshi Nabeshima ◽

Theingi Win Myat ◽

Moh Moh Htun ◽

...

Keyword(s):

Dengue Virus ◽

Disease Severity ◽

Transmission Efficiency ◽

Serum Samples ◽

Genotype I ◽

Denv Serotypes ◽

Public Health Burden ◽

Viral Loads ◽

Epidemic Dynamics ◽

Significant Public Health

Dengue fever, caused by the mosquito-borne dengue virus (DENV), has been endemic in Myanmar since 1970 and it has become a significant public health burden. It is crucial that circulating DENV strains are identified and monitored, and that their transmission efficiency and association with disease severity is understood. In this study, we analyzed DENV-1, DENV-2, DENV-3, and DENV-4 serotypes in 1235 serum samples collected in Myanmar between 2017 and 2019. Whole-genome sequencing of DENV-1–4 demonstrated that most DENV-1–4 strains had been circulating in Myanmar for several years. We also identified the emergence of DENV-3 genotype-I in 2017 samples, which persisted through 2018 and 2019. The emergence of the strain coincided with a period of increased DENV-3 cases and marked changes in the serotype dynamics. Nevertheless, we detected no significant differences between serum viral loads, disease severity, and infection status of individuals infected with different DENV serotypes during the 3-year study. Our results not only identify the spread of a new DENV-3 genotype into Yangon, Myanmar, but also support the importance of DENV evolution in changing the epidemic dynamics in endemic regions.

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Genetic Diversity of Dengue Virus in Clinical Specimens from Bangkok, Thailand, during 2018–2020: Co-Circulation of All Four Serotypes with Multiple Genotypes and/or Clades

Tropical Medicine and Infectious Disease ◽

10.3390/tropicalmed6030162 ◽

2021 ◽

Vol 6 (3) ◽

pp. 162

Author(s):

Kanaporn Poltep ◽

Juthamas Phadungsombat ◽

Emi E. Nakayama ◽

Nathamon Kosoltanapiwat ◽

Borimas Hanboonkunupakarn ◽

...

Keyword(s):

Genetic Diversity ◽

Dengue Virus ◽

Denv Infection ◽

Serum Samples ◽

Genotype I ◽

Denv Serotypes ◽

Genotype Iii ◽

The Relationship ◽

Arboviral Disease ◽

Dominant Genotype

Dengue is an arboviral disease highly endemic in Bangkok, Thailand. To characterize the current genetic diversity of dengue virus (DENV), we recruited patients with suspected DENV infection at the Hospital for Tropical Diseases, Bangkok, during 2018–2020. We determined complete nucleotide sequences of the DENV envelope region for 111 of 276 participant serum samples. All four DENV serotypes were detected, with the highest proportion being DENV-1. Although all DENV-1 sequences were genotype I, our DENV-1 sequences were divided into four distinct clades with different distributions in Asian countries. Two genotypes of DENV-2 were identified, Asian I and Cosmopolitan, which were further divided into two and three distinct clades, respectively. In DENV-3, in addition to the previously dominant genotype III, a cluster of 6 genotype I viruses only rarely reported in Thailand was also observed. All of the DENV-4 viruses belonged to genotype I, but they were separated into three distinct clades. These results indicated that all four serotypes of DENV with multiple genotypes and/or clades co-circulate in Bangkok. Continuous investigation of DENV is warranted to further determine the relationship between DENV within Thailand and neighboring countries in Southeast Asia and Asia.

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An Outbreak of Dengue Virus Serotype 2 Cosmopolitan Genotype in Nepal, 2017

Viruses ◽

10.3390/v13081444 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1444

Author(s):

Ngwe Tun Ngwe Tun ◽

Kishor Pandey ◽

Takeshi Nabeshima ◽

Aung Kyaw Kyaw ◽

Mandira Adhikari ◽

...

Keyword(s):

Dengue Virus ◽

Genome Sequence ◽

Neglected Tropical Diseases ◽

Phylogenetic Analyses ◽

Molecular Techniques ◽

Whole Genome Sequence ◽

Serum Samples ◽

Denv Serotypes ◽

Genomic Study ◽

Virus Serotype

Dengue virus (DENV) is one of the most prevalent neglected tropical diseases, with half of the world’s population at risk of infection. In Nepal, DENV was first reported in 2004, and its prevalence is increasing every year. The present study aimed to obtain and characterize the full-length genome sequence of DENV from the 2017 outbreak. Hospital-based surveillance was conducted in two provinces of Nepal during the outbreak. Acute-phase serum samples were collected from 141 clinically suspected dengue patients after the rainy season. By serological and molecular techniques, 37 (26.9%) and 49 (34.8%), respectively, were confirmed as dengue patients. The cosmopolitan genotype of DENV-2 was isolated from 27 laboratory-confirmed dengue patients. Genomic analysis showed many amino acid substitutions distributed mainly among the E, NS3, and NS5 genes. Phylogenetic analyses of the whole genome sequence revealed two clades (Asian and Indian) among DENV-2 isolates from Nepal. The DENV isolates from hilly and Terai areas were similar to Asian and Indian strains, respectively. Further genomic study on different DENV serotypes is warranted to understand DENV epidemics in Nepal, where there are limited scientific resources and infrastructure.

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Development of an Antigen Capture Immunoassay Based on Monoclonal Antibodies Specific for Dengue Virus Serotype 2 Nonstructural Protein 1 for Early and Rapid Identification of Dengue Virus Serotype 2 Infections

Clinical and Vaccine Immunology ◽

10.1128/cvi.00212-08 ◽

2008 ◽

Vol 16 (1) ◽

pp. 88-95 ◽

Cited By ~ 24

Author(s):

Li-wen Qiu ◽

Biao Di ◽

Kun Wen ◽

Xin-shuai Wang ◽

Wei-hua Liang ◽

...

Keyword(s):

Dengue Virus ◽

Nonstructural Protein ◽

Rapid Identification ◽

Serum Samples ◽

Denv Serotypes ◽

Nonstructural Protein 1 ◽

Antigen Capture ◽

Virus Serotype ◽

Ns1 Antigen ◽

Dengue Virus Serotype 2

ABSTRACT The dengue virus (DENV) has four distinct serotypes (DENV1, DENV2, DENV3, and DENV4) that require differentiation for effective prevention of morbid diseases. The recently developed DENV1-specific NS1 antigen capture enzyme-linked immunosorbent assay (ELISA) based on the monoclonal antibodies (MAbs) that recognize distinct epitopes on nonstructural protein 1 (NS1) of a specific DENV serotype is convenient and cost-effective, but assays have not yet been developed for DENV serotypes 2 to 4. This paper describes the development and validation of a DENV2-specific NS1 antigen capture ELISA by selection and optimization of the pair of well-characterized MAbs that recognized epitopes specific for DENV2 NS1 from a large panel of MAbs. The DENV2 NS1 ELISA displayed exclusive sensitivity with the DENV2 serotype and did not cross-react with the other three DENV serotypes. The sensitivity and specificity of the DENV2 NS1 ELISA were 83.3% (25/30) and 100% (504/504) when used to test 30 acute-phase serum samples from patients infected with DENV2 identified by virus isolation or reverse transcription-PCR serotyping and 504 serum samples from healthy individuals, respectively. The specificity of this assay was also evaluated using a panel of serum samples which were positive for DENV1, other flaviviruses, and nonflaviviruses; no cross-reactions were observed in these clinical samples. The DENV2 NS1 ELISA was eightfold more sensitive than a commercially available serotype-cross-reactive NS1 ELISA (Panbio Diagnostics, Brisbane, Australia) when the two assays were used to test the DENV2-infected cell culture supernatants in parallel. The Panbio NS1 ELISA displayed variation in sensitivity between DENV serotypes. The DENV2-specific NS1 antigen capture ELISA can be used as a tool for the rapid identification of DENV2 infections.

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Inapparent dengue virus infection among students in Mandalay, Myanmar

Transactions of the Royal Society of Tropical Medicine and Hygiene ◽

10.1093/trstmh/trz071 ◽

2019 ◽

Author(s):

Aung Kyaw Kyaw ◽

Mya Myat Ngwe Tun ◽

Shine Thura Naing ◽

Thida ◽

Thein Thein Htwe ◽

...

Keyword(s):

Dengue Virus ◽

Clinical Manifestations ◽

Denv Infection ◽

Rt Pcr ◽

Serum Samples ◽

Cross Sectional ◽

Denv Serotypes ◽

Secondary Infections ◽

Serotype 1 ◽

History Of

AbstractBackgroundA school- and laboratory-based cross-sectional descriptive study was conducted to find out the burden of inapparent dengue virus (DENV) infection in Mandalay where DENV is endemic and there is circulation of all four DENV serotypes.MethodsA total of 420 students who had no history of fever and visited the hospital within 6 months were recruited from three monastic schools. Serum samples were collected and the DENV genome was checked by conventional one-step RT-PCR and anti-DENV IgM and IgG antibodies were determined. Inapparent dengue (DEN) infection is defined as individuals who were either RT-PCR-positive or anti-DENV IgM-positive with no clinical manifestations or mild symptoms, and which are not linked to a visit to a healthcare provider.ResultsAmong 420 students, 38 students (9.0%, 95% CI, 6.4 to 12.2) were confirmed as recent inapparent DEN infection. The DENV serotype-1 was detected in six students. Thirty-one out of 38 (81.6%) laboratory-confirmed inapparent DEN-infected students had primary infections and seven (18.4%) had secondary infections.ConclusionThis study explored the prevalence of inapparent DEN infection rate in urban monastic schools in Mandalay and showed that the rate of primary infection among inapparent DENV-infected children was high.

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All four dengue virus serotypes co-circulate in concurrent dengue infections in a single dengue session in Chittagong, Bangladesh

Bioresearch Communications ◽

10.3329/brc.v8i1.57042 ◽

2021 ◽

Vol 8 (1) ◽

pp. 1042-1048

Author(s):

Moushumi Ghosh Roy ◽

Kutub Uddin ◽

Din Islam ◽

Anjuvan Singh ◽

Mohammad Monirul Islam

Keyword(s):

Dengue Virus ◽

Dengue Fever ◽

Disease Severity ◽

Clinical Symptoms ◽

Global Public Health ◽

Rt Pcr ◽

Serum Samples ◽

Dengue Disease ◽

Denv Serotypes ◽

Public Health Burden

Purposes: Dengue fever, a mosquito-borne viral disease, is a global public health burden affecting millions of people each year and over 40% of world populations are at risk of dengue. Therefore, prompt and accurate dengue diagnosis is inevitable for disease surveillance and for aiding disease management. In this study we report dengue virus (DENV) seroprevalence in Chittagong, Bangladesh along with clinical manifestation of dengue infections. Methods: All samples included in this study were selected based on dengue NS1-based diagnosis, clinical sign and symptoms were judged by expert clinical physicians and infecting DENV serotyping was done by RT-PCR. The blood cells (Platelet, Haematocrit, WBC etc) were analyzed using Haematology cell counter. Results: First, among the 112 DENV infected serum samples tested by RT-PCR, 42 were DENV positive where 76% samples had single DENV serotype infection and 24% were concurrently infected with two or more DENV serotypes, indicating that all four DENVs were present in a single dengue session in Chittagong, Bangladesh. Then, DENV4 was the most prevailed serotype, followed by DENV2, DENV1 and DENV3 in single DENV serotype infections. However, in almost 90% cases of concurrent multiple DENV infections DENV1 serotype was present. A detail analysis of clinical data clearly indicated that DENV1 and DENV2 resulted very similar patterns of clinical symptoms which were quite different from those caused by DENV3 and DENV4. For example, ache and pain were absent in DENV3 infection and diarrhea was absent in DENV4 infections. Furthermore, DENV3, both in single and concurrent multiple DENV infections, might increase dengue disease severity as observed highly reduced platelet counts along with increased WBC in patients infected with DENV3 serotype. Conclusion: All four DENV serotypes, both as single and concurrent multiple DENV infections, were present in single dengue session in Bangladesh. Despite having very similar sequences and structures all four DENVs might produce different disease spectra, ranging from classical dengue fever to dengue hemorrhagic fever. Concurrent multiple DENV infections could contribute increased dengue disease severity in dengue outbreaks in Bangladesh. Bioresearch Commu. 8(1): 1042-1048, 2022 (January)

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