scholarly journals Boosting can explain patterns of fluctuations of ratios of inapparent to symptomatic dengue virus infections

2021 ◽  
Vol 118 (14) ◽  
pp. e2013941118
Author(s):  
Laura W. Alexander ◽  
Rotem Ben-Shachar ◽  
Leah C. Katzelnick ◽  
Guillermina Kuan ◽  
Angel Balmaseda ◽  
...  

Dengue is the most prevalent arboviral disease worldwide, and the four dengue virus (DENV) serotypes circulate endemically in many tropical and subtropical regions. Numerous studies have shown that the majority of DENV infections are inapparent, and that the ratio of inapparent to symptomatic infections (I/S) fluctuates substantially year-to-year. For example, in the ongoing Pediatric Dengue Cohort Study (PDCS) in Nicaragua, which was established in 2004, the I/S ratio has varied from 16.5:1 in 2006–2007 to 1.2:1 in 2009–2010. However, the mechanisms explaining these large fluctuations are not well understood. We hypothesized that in dengue-endemic areas, frequent boosting (i.e., exposures to DENV that do not lead to extensive viremia and result in a less than fourfold rise in antibody titers) of the immune response can be protective against symptomatic disease, and this can explain fluctuating I/S ratios. We formulate mechanistic epidemiologic models to examine the epidemiologic effects of protective homologous and heterologous boosting of the antibody response in preventing subsequent symptomatic DENV infection. We show that models that include frequent boosts that protect against symptomatic disease can recover the fluctuations in the I/S ratio that we observe, whereas a classic model without boosting cannot. Furthermore, we show that a boosting model can recover the inverse relationship between the number of symptomatic cases and the I/S ratio observed in the PDCS. These results highlight the importance of robust dengue control efforts, as intermediate dengue control may have the potential to decrease the protective effects of boosting.

2016 ◽  
Vol 113 (3) ◽  
pp. 728-733 ◽  
Author(s):  
Leah C. Katzelnick ◽  
Magelda Montoya ◽  
Lionel Gresh ◽  
Angel Balmaseda ◽  
Eva Harris

The four dengue virus serotypes (DENV1–4) are mosquito-borne flaviviruses that infect ∼390 million people annually; up to 100 million infections are symptomatic, and 500,000 cases progress to severe disease. Exposure to a heterologous DENV serotype, the specific infecting DENV strains, and the interval of time between infections, as well as age, ethnicity, genetic polymorphisms, and comorbidities of the host, are all risk factors for severe dengue. In contrast, neutralizing antibodies (NAbs) are thought to provide long-lived protection against symptomatic infection and severe dengue. The objective of dengue vaccines is to provide balanced protection against all DENV serotypes simultaneously. However, the association between homotypic and heterotypic NAb titers and protection against symptomatic infection remains poorly understood. Here, we demonstrate that the titer of preinfection cross-reactive NAbs correlates with reduced likelihood of symptomatic secondary infection in a longitudinal pediatric dengue cohort in Nicaragua. The protective effect of NAb titers on infection outcome remained significant when controlled for age, number of years between infections, and epidemic force, as well as with relaxed or more stringent criteria for defining inapparent DENV infections. Further, individuals with higher NAb titers immediately after primary infection had delayed symptomatic infections compared with those with lower titers. However, overall NAb titers increased modestly in magnitude and remained serotype cross-reactive in the years between infections, possibly due to reexposure. These findings establish that anti-DENV NAb titers correlate with reduced probability of symptomatic DENV infection and provide insights into longitudinal characteristics of antibody-mediated immunity to DENV in an endemic setting.


2021 ◽  
Vol 6 (3) ◽  
pp. 162
Author(s):  
Kanaporn Poltep ◽  
Juthamas Phadungsombat ◽  
Emi E. Nakayama ◽  
Nathamon Kosoltanapiwat ◽  
Borimas Hanboonkunupakarn ◽  
...  

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.


2020 ◽  
Vol 222 (4) ◽  
pp. 590-600 ◽  
Author(s):  
Paulina Andrade ◽  
Parnal Narvekar ◽  
Magelda Montoya ◽  
Daniela Michlmayr ◽  
Angel Balmaseda ◽  
...  

Abstract Background The 4 antigenically distinct serotypes of dengue virus (DENV) share extensive homology with each other and with the closely related Zika flavivirus (ZIKV). The development of polyclonal memory B cells (MBCs) to the 4 DENV serotypes and ZIKV during DENV infection is not fully understood. Methods In this study, we analyzed polyclonal MBCs at the single-cell level from peripheral blood mononuclear cells collected ~2 weeks or 6–7 months postprimary or postsecondary DENV infection from a pediatric hospital-based study in Nicaragua using a Multi-Color FluoroSpot assay. Results Dengue virus elicits robust type-specific and cross-reactive MBC responses after primary and secondary DENV infection, with a significantly higher cross-reactive response in both. Reactivity to the infecting serotype dominated the total MBC response. Although the frequency and proportion of type-specific and cross-reactive MBCs were comparable between primary and secondary DENV infections, within the cross-reactive response, the breadth of MBC responses against different serotypes was greater after secondary DENV infection. Dengue virus infection also induced cross-reactive MBC responses recognizing ZIKV, particularly after secondary DENV infection. Conclusions Overall, our study sheds light on the polyclonal MBC response to DENV and ZIKV in naive and DENV-preimmune subjects, with important implications for natural infections and vaccine development.


2018 ◽  
Vol 57 (2) ◽  
Author(s):  
Jasmine Tyson ◽  
Wen-Yang Tsai ◽  
Jih-Jin Tsai ◽  
Carlos Brites ◽  
Ludvig Mässgård ◽  
...  

ABSTRACTThe recent outbreaks of Zika virus (ZIKV) and associated birth defects in regions of dengue virus (DENV) endemicity emphasize the need for sensitive and specific serodiagnostic tests. We reported previously that enzyme-linked immunosorbent assays (ELISAs) based on the nonstructural protein 1 (NS1) of DENV serotype 1 (DENV1) and ZIKV can distinguish primary DENV1, secondary DENV, and ZIKV infections. Whether ELISAs based on NS1 proteins of other DENV serotypes can discriminate various DENV and ZIKV infections remains unknown. We herein developed DENV2, DENV3, and DENV4 NS1 IgG ELISAs to test convalescent- and postconvalescent-phase samples from reverse transcription-PCR-confirmed cases, including 25 primary DENV1, 24 primary DENV2, 10 primary DENV3, 67 secondary DENV, 36 primary West Nile virus, 38 primary ZIKV, and 35 ZIKV with previous DENV infections as well as 55 flavivirus-naive samples. Each ELISA detected primary DENV infection with a sensitivity of 100% for the same serotype and 23.8% to 100% for different serotypes. IgG ELISA using a mixture of DENV1-4 NS1 proteins detected different primary and secondary DENV infections with a sensitivity of 95.6% and specificity of 89.5%. The ZIKV NS1 IgG ELISA detected ZIKV infection with a sensitivity of 100% and specificity of 82.9%. On the basis of the relative optical density ratio, the combination of DENV1-4 and ZIKV NS1 IgG ELISAs distinguished ZIKV with previous DENV and secondary DENV infections with a sensitivity of 91.7% to 94.1% and specificity of 87.0% to 95.0%. These findings have important applications to serodiagnosis, serosurveillance, and monitoring of both DENV and ZIKV infections in regions of endemicity.


2019 ◽  
Vol 20 (10) ◽  
pp. 2382 ◽  
Author(s):  
Juliano G. Haddad ◽  
Andrea Cristine Koishi ◽  
Arnaud Gaudry ◽  
Claudia Nunes Duarte dos Santos ◽  
Wildriss Viranaicken ◽  
...  

Zika virus (ZIKV) and Dengue virus (DENV) are mosquito-borne viruses of the Flavivirus genus that could cause congenital microcephaly and hemorrhage, respectively, in humans, and thus present a risk to global public health. A preventive vaccine against ZIKV remains unavailable, and no specific antiviral drugs against ZIKV and DENV are licensed. Medicinal plants may be a source of natural antiviral drugs which mostly target viral entry. In this study, we evaluate the antiviral activity of Doratoxylum apetalum, an indigenous medicinal plant from the Mascarene Islands, against ZIKV and DENV infection. Our data indicated that D. apetalum exhibited potent antiviral activity against a contemporary epidemic strain of ZIKV and clinical isolates of four DENV serotypes at non-cytotoxic concentrations in human cells. Time-of-drug-addition assays revealed that D. apetalum extract acts on ZIKV entry by preventing the internalisation of virus particles into the host cells. Our data suggest that D. apetalum-mediated ZIKV inhibition relates to virus particle inactivation. We suggest that D. apetalum could be a promising natural source for the development of potential antivirals against medically important flaviviruses.


2014 ◽  
Vol 8 (07) ◽  
pp. 876-884 ◽  
Author(s):  
Diana Carolina Quintero-Gil ◽  
Marta Ospina ◽  
Jorge Emilio Osorio-Benitez ◽  
Marlen Martinez-Gutierrez

Introduction: Different dengue virus (DENV) serotypes have been associated with greater epidemic potential. In turn, the increased frequency in cases of severe forms of dengue has been associated with the cocirculation of several serotypes. Because Colombia is a country with an endemic presence of all four DENV serotypes, the aim of this study was to evaluate the in vivo and in vitro replication of the DENV-2 and DENV-3 strains under individual infection and coinfection conditions. Methodology: C6/36HT cells were infected with the two strains individually or simultaneously (coinfection). Replication capacity was evaluated by RT-qPCR, and the effects on cell viability were assessed with an MTT (3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. Additionally, Aedes aegypti mosquitoes were artificially fed the two strains of each serotype individually or simultaneously. The viral genomes were quantified by RT-qPCR and the survival of the infected mosquitoes was compared to that of uninfected controls. Results: In single infections, three strains significantly affected C6/36HT cell viability, but no significant differences were found in the replication capacities of the strains of the same serotype. In the in vivo infections, mosquito survival was not affected, and no significant differences in replication between strains of the same serotype were found. Finally, in coinfections, serotype 2 replicated with a thousandfold greater efficiency than serotype 3 did both in vitro and in vivo. Conclusions: Due to the cocirculation of serotypes in endemic regions, further studies of coinfections in a natural environment would further an understanding of the transmission dynamics that affect DENV infection epidemiology.


2014 ◽  
Vol 95 (3) ◽  
pp. 591-600 ◽  
Author(s):  
Meng Ling Moi ◽  
Tomohiko Takasaki ◽  
Tsutomu Omatsu ◽  
Shinichiro Nakamura ◽  
Yuko Katakai ◽  
...  

There are four dengue virus (DENV) serotypes. Primary infection with one does not confer protective immunity against the others. We have reported previously that the marmoset (Callithrix jacchus) is a useful primary DENV infection model. It has been reported that secondary DENV infection with a heterotypic serotype induces viraemia kinetics and antibody responses that differ from those in primary infection. Thus, it is important to determine the utility of the marmoset as a model for secondary DENV infection. Marmosets were infected with heterologous DENV by secondary inoculation, and viraemia kinetics and antibody responses were analysed. The marmosets consistently developed high levels of viraemia after the secondary inoculation with heterologous DENV serotypes. IgM responses were lower compared with primary inoculation responses, whilst IgG responses were rapid and high. Neutralizing activities, which possessed serotype cross-reactive activities, were detected as early as 4 days after inoculation. In addition, infectious viraemia titres were higher when assayed with Fcγ receptor-expressing baby hamster kidney (BHK) cells than when assayed with conventional BHK cells, suggesting the presence of infectious virus–antibody immune complexes. After secondary infection with heterotypic DENV, the marmosets demonstrated viraemia kinetics, IgM and IgG responses, and high levels of serotype cross-reactive neutralizing antibody responses, all of which were consistent with secondary DENV infection in humans. The results indicate the marmoset as a useful animal for studying secondary, as well as primary, DENV infection.


2010 ◽  
Vol 84 (16) ◽  
pp. 8332-8341 ◽  
Author(s):  
Dong Jiang ◽  
Jessica M. Weidner ◽  
Min Qing ◽  
Xiao-Ben Pan ◽  
Haitao Guo ◽  
...  

ABSTRACT Interferons (IFNs) are key mediators of the host innate antiviral immune response. To identify IFN-stimulated genes (ISGs) that instigate an antiviral state against two medically important flaviviruses, West Nile virus (WNV) and dengue virus (DENV), we tested 36 ISGs that are commonly induced by IFN-α for antiviral activity against the two viruses. We discovered that five ISGs efficiently suppressed WNV and/or DENV infection when they were individually expressed in HEK293 cells. Mechanistic analyses revealed that two structurally related cell plasma membrane proteins, IFITM2 and IFITM3, disrupted early steps (entry and/or uncoating) of the viral infection. In contrast, three IFN-induced cellular enzymes, viperin, ISG20, and double-stranded-RNA-activated protein kinase, inhibited steps in viral proteins and/or RNA biosynthesis. Our results thus imply that the antiviral activity of IFN-α is collectively mediated by a panel of ISGs that disrupt multiple steps of the DENV and WNV life cycles.


mBio ◽  
2011 ◽  
Vol 2 (6) ◽  
Author(s):  
Panisadee Avirutnan ◽  
Richard E. Hauhart ◽  
Mary A. Marovich ◽  
Peter Garred ◽  
John P. Atkinson ◽  
...  

ABSTRACTMannose-binding lectin (MBL) is a key soluble pathogen recognition protein of the innate immune system that binds specific mannose-containing glycans on the surfaces of microbial agents and initiates complement activation via the lectin pathway. Prior studies showed that MBL-dependent activation of the complement cascade neutralized insect cell-derived West Nile virus (WNV) in cell culture and restricted pathogenesis in mice. Here, we investigated the antiviral activity of MBL in infection by dengue virus (DENV), a related flavivirus. Using a panel of naïve sera from mouse strains deficient in different complement components, we showed that inhibition of infection by insect cell- and mammalian cell-derived DENV was primarily dependent on the lectin pathway. Human MBL also bound to DENV and neutralized infection of all four DENV serotypes through complement activation-dependent and -independent pathways. Experiments with human serum from naïve individuals with inherent variation in the levels of MBL in blood showed a direct correlation between the concentration of MBL and neutralization of DENV; samples with high levels of MBL in blood neutralized DENV more efficiently than those with lower levels. Our studies suggest that allelic variation of MBL in humans may impact complement-dependent control of DENV pathogenesis.IMPORTANCEDengue virus (DENV) is a mosquito-transmitted virus that causes a spectrum of clinical disease in humans ranging from subclinical infection to dengue hemorrhagic fever and dengue shock syndrome. Four serotypes of DENV exist, and severe illness is usually associated with secondary infection by a different serotype. Here, we show that mannose-binding lectin (MBL), a pattern recognition molecule that initiates the lectin pathway of complement activation, neutralized infection of all four DENV serotypes through complement activation-dependent and -independent pathways. Moreover, we observed a direct correlation with the concentration of MBL in human serum and neutralization of DENV infection. Our studies suggest that common genetic polymorphisms that result in disparate levels and function of MBL in humans may impact DENV infection, pathogenesis, and disease severity.


Sensors ◽  
2021 ◽  
Vol 21 (23) ◽  
pp. 7809
Author(s):  
Kanaporn Poltep ◽  
Emi E. Nakayama ◽  
Tadahiro Sasaki ◽  
Takeshi Kurosu ◽  
Yoshiki Takashima ◽  
...  

Four serotypes of dengue virus (DENV), type 1 to 4 (DENV-1 to DENV-4), exhibit approximately 25–40% of the difference in the encoded amino acid residues of viral proteins. Reverse transcription of RNA extracted from specimens followed by PCR amplification is the current standard method of DENV serotype determination. However, since this method is time-consuming, rapid detection systems are desirable. We established several mouse monoclonal antibodies directed against DENV non-structural protein 1 and integrated them into rapid DENV detection systems. We successfully developed serotype-specific immunochromatography systems for all four DENV serotypes. Each system can detect 104 copies/mL in 15 min using laboratory and clinical isolates of DENV. No cross-reaction between DENV serotypes was observed in these DENV isolates. We also confirmed that there was no cross-reaction with chikungunya, Japanese encephalitis, Sindbis, and Zika viruses. Evaluation of these systems using serum from DENV-infected individuals indicated a serotype specificity of almost 100%. These assay systems could accelerate both DENV infection diagnosis and epidemiologic studies in DENV-endemic areas.


Sign in / Sign up

Export Citation Format

Share Document