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Amaya-Larios IY, Rojas-Russell M, López-Cervantes M, Castro-Porras L, Castro-Borbonio MV, Sarti E, Puentes-Rosas E, Tirado-Gómez LL, Olaíz-Fernandez G, Ramos-Castañeda J. Seroprevalence of dengue in school children in Mexico ages 6-17 years, 2016. Trans R Soc Trop Med Hyg 2019; 112:223-229. [PMID: 29917129 PMCID: PMC6030845 DOI: 10.1093/trstmh/try046] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Accepted: 05/03/2018] [Indexed: 11/21/2022] Open
Abstract
Background Dengue is the most important arboviral disease in the world. Seroprevalence has been proposed as a marker of endemicity, however, studies are scarce. Methods We conducted a cross-sectional, stratified cluster, random sample study to measure the seroprevalence of antibodies to dengue virus (DENV) in Mexico. The target population was school children ages 6–17 y from 22 endemic states in Mexico, clustered in four regions: Pacific, South-Central, Southeast and Low. Results A total of 2134 subjects provided blood samples for immunoglobulin G antibody detection in serum by enzyme-linked immunosorbent assay. Overall, the seroprevalence of antibodies against DENV was 33.5% (95% confidence interval [CI] 27.5 to 40.1). The Southeast had the highest regional seroprevalence, reaching 70.9% (95% CI 60.3 to 79.7). Seroprevalence was higher in older children in the Southeast region: 62.1% (95% CI 46.9 to 75.2) in children 6–8 y and 82.6% (95% CI 73.8 to 88.9) in 13–17 years old (y). However, this was not consistent in all regions. Seroprevalence was associated with dengue incidence. Conclusions DENV seroprevalence in Mexico was found to be heterogeneous at the country, regional and state levels. Seroprevalence was linked to long-term exposure and did not adequately reflect recent patterns of transmission, suggesting that utilization of a single epidemiological indicator to define endemic regions should be avoided.
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Affiliation(s)
- Irma Y Amaya-Larios
- Instituto Nacional de Salud Publica. Centro de Investigaciones sobre Enfermedades Infecciosas, Cuernavaca, Morelos. CP, Mexico
| | - Mario Rojas-Russell
- Universidad Nacional Autonoma de Mexico, Centro de Investigaciones en Politica, Poblacion y Salud, Mexico City, CP, Mexico
| | | | - Lilia Castro-Porras
- Universidad Nacional Autonoma de Mexico, Centro de Investigaciones en Politica, Poblacion y Salud, Mexico City, CP, Mexico
| | - Ma Victoria Castro-Borbonio
- Universidad Nacional Autonoma de Mexico, Centro de Investigaciones en Politica, Poblacion y Salud, Mexico City, CP, Mexico
| | | | | | - Laura L Tirado-Gómez
- Universidad Nacional Autonoma de Mexico, Centro de Investigaciones en Politica, Poblacion y Salud, Mexico City, CP, Mexico
| | - Gustavo Olaíz-Fernandez
- Universidad Nacional Autonoma de Mexico, Centro de Investigaciones en Politica, Poblacion y Salud, Mexico City, CP, Mexico
| | - José Ramos-Castañeda
- Instituto Nacional de Salud Publica. Centro de Investigaciones sobre Enfermedades Infecciosas, Cuernavaca, Morelos. CP, Mexico.,Center for Tropical Diseases, University of Texas-Medical Branch, Center for Tropical Diseases, Galveston, Texas, USA
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Tsang TK, Ghebremariam SL, Gresh L, Gordon A, Halloran ME, Katzelnick LC, Rojas DP, Kuan G, Balmaseda A, Sugimoto J, Harris E, Longini IM, Yang Y. Effects of infection history on dengue virus infection and pathogenicity. Nat Commun 2019; 10:1246. [PMID: 30886145 PMCID: PMC6423047 DOI: 10.1038/s41467-019-09193-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Accepted: 02/21/2019] [Indexed: 12/25/2022] Open
Abstract
The understanding of immunological interactions among the four dengue virus (DENV) serotypes and their epidemiological implications is often hampered by the lack of individual-level infection history. Using a statistical framework that infers full infection history, we analyze a prospective pediatric cohort in Nicaragua to characterize how infection history modulates the risks of DENV infection and subsequent clinical disease. After controlling for age, one prior infection is associated with 54% lower, while two or more are associated with 91% higher, risk of a new infection, compared to DENV-naive children. Children >8 years old have 55% and 120% higher risks of infection and subsequent disease, respectively, than their younger peers. Among children with ≥1 prior infection, intermediate antibody titers increase, whereas high titers lower, the risk of subsequent infection, compared with undetectable titers. Such complex dependency needs to be considered in the design of dengue vaccines and vaccination strategies.
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Affiliation(s)
- Tim K Tsang
- Department of Biostatistics, College of Public Health and Health Professions, University of Florida, Gainesville, FL, 32611, USA
| | - Samson L Ghebremariam
- Department of Biostatistics, College of Public Health and Health Professions, University of Florida, Gainesville, FL, 32611, USA
| | - Lionel Gresh
- Sustainable Sciences Institute, Managua, 14007, Nicaragua
| | - Aubree Gordon
- Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, MI, 48109, USA
| | - M Elizabeth Halloran
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA, 98109, USA
- Department of Biostatistics, University of Washington, Seattle, WA, 98195, USA
| | - Leah C Katzelnick
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, CA, 94720, USA
| | - Diana Patricia Rojas
- Department of Biostatistics, College of Public Health and Health Professions, University of Florida, Gainesville, FL, 32611, USA
| | - Guillermina Kuan
- Centro de Salud Sócrates Flores Vivas, Ministry of Health, Managua, 12014, Nicaragua
| | - Angel Balmaseda
- Laboratorio Nacional de Virología, Centro Nacional de Diagnóstico y Referencia, Ministry of Health, Managua, 16064, Nicaragua
| | - Jonathan Sugimoto
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA, 98109, USA
| | - Eva Harris
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, CA, 94720, USA.
| | - Ira M Longini
- Department of Biostatistics, College of Public Health and Health Professions, University of Florida, Gainesville, FL, 32611, USA.
- Emerging Pathogens Institute, University of Florida, Gainesville, FL, 32610, USA.
| | - Yang Yang
- Department of Biostatistics, College of Public Health and Health Professions, University of Florida, Gainesville, FL, 32611, USA.
- Emerging Pathogens Institute, University of Florida, Gainesville, FL, 32610, USA.
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Villanes A, Griffiths E, Rappa M, Healey CG. Dengue Fever Surveillance in India Using Text Mining in Public Media. Am J Trop Med Hyg 2018; 98:181-191. [PMID: 29141718 PMCID: PMC5928697 DOI: 10.4269/ajtmh.17-0253] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Despite the improvement in health conditions across the world, communicable diseases remain among the leading mortality causes in many countries. Combating communicable diseases depends on surveillance, preventive measures, outbreak investigation, and the establishment of control mechanisms. Delays in obtaining country-level data of confirmed communicable disease cases, such as dengue fever, are prompting new efforts for short- to medium-term data. News articles highlight dengue infections, and they can reveal how public health messages, expert findings, and uncertainties are communicated to the public. In this article, we analyze dengue news articles in Asian countries, with a focus in India, for each month in 2014. We investigate how the reports cluster together, and uncover how dengue cases, public health messages, and research findings are communicated in the press. Our main contributions are to 1) uncover underlying topics from news articles that discuss dengue in Asian countries in 2014; 2) construct topic evolution graphs through the year; and 3) analyze the life cycle of dengue news articles in India, then relate them to rainfall, monthly reported dengue cases, and the Breteau Index. We show that the five main topics discussed in the newspapers in Asia in 2014 correspond to 1) prevention; 2) reported dengue cases; 3) politics; 4) prevention relative to other diseases; and 5) emergency plans. We identify that rainfall has 0.92 correlation with the reported dengue cases extracted from news articles. Based on our findings, we conclude that the proposed method facilitates the effective discovery of evolutionary dengue themes and patterns.
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Affiliation(s)
- Andrea Villanes
- Department of Computer Science, North Carolina State University, Raleigh, North Carolina
| | | | - Michael Rappa
- Department of Computer Science, North Carolina State University, Raleigh, North Carolina
| | - Christopher G Healey
- Department of Computer Science, North Carolina State University, Raleigh, North Carolina
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Haroon M, Jan H, Faisal S, Ali N, Kamran M, Ullah F. Dengue Outbreak in Peshawar: Clinical Features and Laboratory Markers of Dengue Virus Infection. J Infect Public Health 2018; 12:258-262. [PMID: 30466902 DOI: 10.1016/j.jiph.2018.10.138] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2018] [Revised: 10/16/2018] [Accepted: 10/30/2018] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Dengue is a tropical disease caused by dengue virus (DENV). It is one of the most significant arthropod-borne viral infection. OBJECTIVES The aim of the current study was to characterize epidemiological, clinical features and laboratory markers of dengue infection during the recent epidemic in Peshawar, KP. METHODS During the prospective hospital-based observational study, 2000 dengue suspected cases were serologically examined at Lady Reading Hospital (LRH) Peshawar. Dengue NS1 antigen and Dengue IgG and IgM antibody ELISA tests were conducted for the confirmation of dengue infection. Data regarding the clinical features, platelet count and liver function tests were also recorded for the dengue positive patients. RESULTS Out of total samples 415 (21%) cases including 309 (74%) male and 106 (25%) female were detected positive for the dengue infection. In the dengue positive patients, the highest prevalence was observed in the age group of 21-40years with 160 (38%) followed by the age group of 1-20years with 89 (21%) patients. Fever was recorded in 100% of the dengue patients followed by a headache and fatigue in 73% and liver abnormality observed in 70% of the cases. During laboratory examinations IgM antibody was detected in 180 cases, followed by IgG antibody in 87, NS1 antigen in 43, NS1 antigen along with IgG and IgM antibodies in 41 dengue positive cases. Another combine detection of NS1 antigen with IgM antibody, NS1 antigen with IgG antibody and both IgG and IgM antibodies was observed in 21, 21, 22 dengue cases respectively. CONCLUSION It was concluded that the dengue infection can be early diagnosed on the basis of described clinical features and with the detection of dengue-specific NS1 antigen along with antibodies such as IgG and IgM.
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Affiliation(s)
- Muhammad Haroon
- Department of Biotechnology, Quaid-i-Azam University, Islamabad, Pakistan.
| | - Hasnain Jan
- Department of Biotechnology, Quaid-i-Azam University, Islamabad, Pakistan
| | - Shah Faisal
- Department of Biotechnology, Bacha Khan University, Charsadda, KP, Pakistan
| | - Nasir Ali
- Department of Biotechnology, Quaid-i-Azam University, Islamabad, Pakistan
| | - Muhammad Kamran
- Department of Biotechnology, Bacha Khan University, Charsadda, KP, Pakistan
| | - Farhan Ullah
- Centre of Biotechnology and Microbiology, University of Peshawar, KP, Pakistan
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Adam A, Schüttoff T, Reiche S, Jassoy C. High seroprevalence of dengue virus indicates that dengue virus infections are frequent in central and eastern Sudan. Trop Med Int Health 2018; 23:960-967. [PMID: 29907989 DOI: 10.1111/tmi.13116] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
OBJECTIVES To determine the seroprevalence of dengue in central and eastern Sudan and the breadth of neutralising antibody responses. METHODS Blood was drawn from 483 patients with fever who visited outpatient clinics in Port Sudan, Red Sea state, in three towns in Kassala state and in El Obeid, North Kordofan, in December 2012 and January 2013. Sera were tested for dengue virus IgG and IgM by ELISA (Panbio) and sera without serologic evidence of acute infection (IgM negative) were used for the analysis of the seroprevalence. DENV neutralisation tests were performed to determine the specificity of the ELISA and to examine the degree of cross-neutralisation of multiple DENV serotypes. RESULTS Sixty-seven per cent (302 of 448) of the sera were dengue virus IgG-positive. The seroprevalence in Port Sudan was 89% (106 of 119 sera), in Kassala 61% (128 of 209) and in North Kordofan 56.7% (68 of 120). Thirty-one of 32 ELISA-positive sera neutralised dengue viruses indicating that the ELISA was highly specific. The majority of the sera broadly neutralised all four dengue virus serotypes indicating multiple infections. CONCLUSIONS The majority of the population in central and eastern Sudan has been infected with dengue viruses, many people repeatedly. The high seroprevalence underscores the need for extended dengue surveillance in Sudan, broad disease awareness in medical institutions and in the population and diagnostic capacity building for severe dengue infections.
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Affiliation(s)
- Awadalkareem Adam
- Institute for Virology, University Clinics and Medical Faculty, University of Leipzig, Leipzig, Germany
| | - Tom Schüttoff
- Institute for Virology, University Clinics and Medical Faculty, University of Leipzig, Leipzig, Germany
| | - Sven Reiche
- Institute for Virology, University Clinics and Medical Faculty, University of Leipzig, Leipzig, Germany
| | - Christian Jassoy
- Institute for Virology, University Clinics and Medical Faculty, University of Leipzig, Leipzig, Germany
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Transmission-clearance trade-offs indicate that dengue virulence evolution depends on epidemiological context. Nat Commun 2018; 9:2355. [PMID: 29907741 PMCID: PMC6003961 DOI: 10.1038/s41467-018-04595-w] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2017] [Accepted: 05/09/2018] [Indexed: 12/20/2022] Open
Abstract
An extensive body of theory addresses the topic of pathogen virulence evolution, yet few studies have empirically demonstrated the presence of fitness trade-offs that would select for intermediate virulence. Here we show the presence of transmission-clearance trade-offs in dengue virus using viremia measurements. By fitting a within-host model to these data, we further find that the interaction between dengue and the host immune response can account for the observed trade-offs. Finally, we consider dengue virulence evolution when selection acts on the virus’s production rate. By combining within-host model simulations with empirical findings on how host viral load affects human-to-mosquito transmission success, we show that the virus’s transmission potential is maximized at production rates associated with intermediate virulence and that the optimal production rate critically depends on dengue’s epidemiological context. These results indicate that long-term changes in dengue’s global distribution impact the invasion and spread of virulent dengue virus genotypes. Theory predicts that pathogens will evolve towards intermediate virulence, yet the necessary trade-offs invoked by this theory have rarely been demonstrated empirically. Here, the authors show that dengue virus dynamics exhibit a trade-off between transmission and clearance rates.
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de Silva AM, Harris E. Which Dengue Vaccine Approach Is the Most Promising, and Should We Be Concerned about Enhanced Disease after Vaccination? The Path to a Dengue Vaccine: Learning from Human Natural Dengue Infection Studies and Vaccine Trials. Cold Spring Harb Perspect Biol 2018; 10:cshperspect.a029371. [PMID: 28716891 DOI: 10.1101/cshperspect.a029371] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Dengue virus (DENV) is the most common arthropod-borne viral disease of humans. Although effective vaccines exist against other flaviviral diseases like yellow fever and Japanese encephalitis, dengue vaccine development is complicated by the presence of four virus serotypes and the possibility of partial immunity enhancing dengue disease severity. Several live attenuated dengue vaccines are being tested in human clinical trials. Initial results are mixed, with variable efficacy depending on DENV serotype and previous DENV exposure. Here, we highlight recent discoveries about the human antibody response to DENV and propose guidelines for advancing development of safe and effective dengue vaccines.
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Affiliation(s)
- Aravinda M de Silva
- Department of Microbiology and Immunology, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599
| | - Eva Harris
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, Berkeley, California 94720-3370
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ten Bosch QA, Clapham HE, Lambrechts L, Duong V, Buchy P, Althouse BM, Lloyd AL, Waller LA, Morrison AC, Kitron U, Vazquez-Prokopec GM, Scott TW, Perkins TA. Contributions from the silent majority dominate dengue virus transmission. PLoS Pathog 2018; 14:e1006965. [PMID: 29723307 PMCID: PMC5933708 DOI: 10.1371/journal.ppat.1006965] [Citation(s) in RCA: 85] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2017] [Accepted: 03/09/2018] [Indexed: 02/07/2023] Open
Abstract
Despite estimates that, each year, as many as 300 million dengue virus (DENV) infections result in either no perceptible symptoms (asymptomatic) or symptoms that are sufficiently mild to go undetected by surveillance systems (inapparent), it has been assumed that these infections contribute little to onward transmission. However, recent blood-feeding experiments with Aedes aegypti mosquitoes showed that people with asymptomatic and pre-symptomatic DENV infections are capable of infecting mosquitoes. To place those findings into context, we used models of within-host viral dynamics and human demographic projections to (1) quantify the net infectiousness of individuals across the spectrum of DENV infection severity and (2) estimate the fraction of transmission attributable to people with different severities of disease. Our results indicate that net infectiousness of people with asymptomatic infections is 80% (median) that of people with apparent or inapparent symptomatic infections (95% credible interval (CI): 0–146%). Due to their numerical prominence in the infectious reservoir, clinically inapparent infections in total could account for 84% (CI: 82–86%) of DENV transmission. Of infections that ultimately result in any level of symptoms, we estimate that 24% (95% CI: 0–79%) of onward transmission results from mosquitoes biting individuals during the pre-symptomatic phase of their infection. Only 1% (95% CI: 0.8–1.1%) of DENV transmission is attributable to people with clinically detected infections after they have developed symptoms. These findings emphasize the need to (1) reorient current practices for outbreak response to adoption of pre-emptive strategies that account for contributions of undetected infections and (2) apply methodologies that account for undetected infections in surveillance programs, when assessing intervention impact, and when modeling mosquito-borne virus transmission. Most dengue virus infections result in either no perceptible symptoms or symptoms that are so mild that they go undetected by surveillance systems. It is unclear how much these infections contribute to the overall transmission and burden of dengue. At an individual level, we show that people with asymptomatic infections are approximately 80% as infectious to mosquitoes as their symptomatic counterparts. At a population level, we show that approximately 88% of infections result from people who display no apparent symptoms at the time of transmission. These results suggest that individuals undetected by surveillance systems may be the primary reservoir of dengue virus transmission and that policy for dengue control and prevention must be revised accordingly.
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Affiliation(s)
- Quirine A. ten Bosch
- Department of Biological Sciences, Eck Institute for Global Health, University of Notre Dame, Notre Dame, IN, United States
- * E-mail: (QAtB); (TAP)
| | - Hannah E. Clapham
- Department of Epidemiology, Johns Hopkins School of Public Health, Baltimore, MD, United States
| | - Louis Lambrechts
- Insect-Virus Interactions Group, Department of Genomes and Genetics, Institut Pasteur, Paris, France
- Centre National de la Recherche Scientifique, Unité Mixte de Recherche 2000, Paris, France
| | - Veasna Duong
- Virology Unit, Institut Pasteur du Cambodge, Institut Pasteur International Network, Phnom Penh, Cambodia
| | - Philippe Buchy
- Virology Unit, Institut Pasteur du Cambodge, Institut Pasteur International Network, Phnom Penh, Cambodia
- GlaxoSmithKline, Vaccines R&D, Singapore
| | - Benjamin M. Althouse
- Institute for Disease Modeling, Bellevue, WA, United States
- Information School, University of Washington, Seattle, WA, United States
- Department of Biology, New Mexico State University, Las Cruces, NM, United States
| | - Alun L. Lloyd
- Department of Mathematics, Biomathematics Graduate Program and Center for Quantitative Sciences in Biomedicine, North Carolina State University, Raleigh, NC, United States
| | - Lance A. Waller
- Department of Biostatistics and Bioinformatics, Rollins School of Public Health, Emory University, Atlanta, GA, United States
| | - Amy C. Morrison
- Department of Entomology and Nematology, University of California, Davis, CA, United States
| | - Uriel Kitron
- Department of Environmental Sciences, Emory University, Atlanta, GA, United States
| | | | - Thomas W. Scott
- Department of Entomology and Nematology, University of California, Davis, CA, United States
| | - T. Alex Perkins
- Department of Biological Sciences, Eck Institute for Global Health, University of Notre Dame, Notre Dame, IN, United States
- * E-mail: (QAtB); (TAP)
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Pollett S, Melendrez MC, Maljkovic Berry I, Duchêne S, Salje H, Cummings DAT, Jarman RG. Understanding dengue virus evolution to support epidemic surveillance and counter-measure development. INFECTION GENETICS AND EVOLUTION 2018; 62:279-295. [PMID: 29704626 DOI: 10.1016/j.meegid.2018.04.032] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Revised: 04/20/2018] [Accepted: 04/24/2018] [Indexed: 11/30/2022]
Abstract
Dengue virus (DENV) causes a profound burden of morbidity and mortality, and its global burden is rising due to the co-circulation of four divergent DENV serotypes in the ecological context of globalization, travel, climate change, urbanization, and expansion of the geographic range of the Ae.aegypti and Ae.albopictus vectors. Understanding DENV evolution offers valuable opportunities to enhance surveillance and response to DENV epidemics via advances in RNA virus sequencing, bioinformatics, phylogenetic and other computational biology methods. Here we provide a scoping overview of the evolution and molecular epidemiology of DENV and the range of ways that evolutionary analyses can be applied as a public health tool against this arboviral pathogen.
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Affiliation(s)
- S Pollett
- Viral Diseases Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA; Marie Bashir Institute, University of Sydney, NSW, Australia; Institute for Global Health Sciences, University of California at San Francisco, CA, USA.
| | - M C Melendrez
- Viral Diseases Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - I Maljkovic Berry
- Viral Diseases Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - S Duchêne
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Australia
| | - H Salje
- Institut Pasteur, Paris, France; Johns Hopkins School of Public Health, Baltimore, MD, USA
| | - D A T Cummings
- Johns Hopkins School of Public Health, Baltimore, MD, USA; University of Florida, FL, USA
| | - R G Jarman
- Viral Diseases Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA
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Long-term epidemiological dynamics of dengue in Barbados - one of the English-speaking Caribbean countries. Epidemiol Infect 2018; 146:1048-1055. [PMID: 29655390 DOI: 10.1017/s0950268818000900] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Using the dengue surveillance program, we prospectively collected data on all the suspected and confirmed cases of dengue in Barbados from 2006 to 2015. Data were analysed for demographic, seasonal and temporal dynamics of this disease in this country. The overall mean annual incidence rate of suspected and confirmed dengue over the study period was 0.49% (range 0.15%-0.99%) and 0.16% (range 0.05%-0.48%), respectively. There was a significant correlation between the mean monthly number of confirmed cases, the mean monthly rainfall and the mean monthly relative humidity percentage. Dengue in this population is predominantly an infection affecting children and young adults. The median age of the patients with both, suspected and confirmed dengue was 25 years and the highest proportion of cases was seen in the age group 0-15 years. The annual incidence rates of both the suspected and the confirmed cases showed an upward trend during the study period and this upward trend was more pronounced among children.
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Gromowski GD, Henein S, Kannadka CB, Barvir DA, Thomas SJ, de Silva AM, Jarman RG. Delineating the serotype-specific neutralizing antibody response to a live attenuated tetravalent dengue vaccine. Vaccine 2018; 36:2403-2410. [DOI: 10.1016/j.vaccine.2018.03.055] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Revised: 02/02/2018] [Accepted: 03/21/2018] [Indexed: 11/16/2022]
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Lourenço J, Tennant W, Faria NR, Walker A, Gupta S, Recker M. Challenges in dengue research: A computational perspective. Evol Appl 2018; 11:516-533. [PMID: 29636803 PMCID: PMC5891037 DOI: 10.1111/eva.12554] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Accepted: 09/08/2017] [Indexed: 01/12/2023] Open
Abstract
The dengue virus is now the most widespread arbovirus affecting human populations, causing significant economic and social impact in South America and South-East Asia. Increasing urbanization and globalization, coupled with insufficient resources for control, misguided policies or lack of political will, and expansion of its mosquito vectors are some of the reasons why interventions have so far failed to curb this major public health problem. Computational approaches have elucidated on dengue's population dynamics with the aim to provide not only a better understanding of the evolution and epidemiology of the virus but also robust intervention strategies. It is clear, however, that these have been insufficient to address key aspects of dengue's biology, many of which will play a crucial role for the success of future control programmes, including vaccination. Within a multiscale perspective on this biological system, with the aim of linking evolutionary, ecological and epidemiological thinking, as well as to expand on classic modelling assumptions, we here propose, discuss and exemplify a few major computational avenues-real-time computational analysis of genetic data, phylodynamic modelling frameworks, within-host model frameworks and GPU-accelerated computing. We argue that these emerging approaches should offer valuable research opportunities over the coming years, as previously applied and demonstrated in the context of other pathogens.
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Affiliation(s)
| | - Warren Tennant
- Centre for Mathematics and the EnvironmentUniversity of ExeterPenrynUK
| | | | | | | | - Mario Recker
- Centre for Mathematics and the EnvironmentUniversity of ExeterPenrynUK
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Katzelnick LC, Harris E. The use of longitudinal cohorts for studies of dengue viral pathogenesis and protection. Curr Opin Virol 2018; 29:51-61. [PMID: 29597086 PMCID: PMC5996389 DOI: 10.1016/j.coviro.2018.03.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Accepted: 03/12/2018] [Indexed: 12/31/2022]
Abstract
In this review, we describe how longitudinal prospective community-based, school-based, and household-based cohort studies contribute to improving our knowledge of viral disease, focusing specifically on contributions to understanding and preventing dengue. We describe how longitudinal cohorts enable measurement of essential disease parameters and risk factors; provide insights into biological correlates of protection and disease risk; enable rapid application of novel biological and statistical technologies; lead to development of new interventions and inform vaccine trial design; serve as sentinels in outbreak conditions and facilitate development of critical diagnostic assays; enable holistic studies on disease in the context of other infections, comorbidities, and environmental risk factors; and build research capacity that strengthens national and global public health response and disease surveillance.
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Affiliation(s)
- Leah C Katzelnick
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, 185 Li Ka Shing Center, 1951 Oxford Street, Berkeley, CA 94720-3370, United States
| | - Eva Harris
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, 185 Li Ka Shing Center, 1951 Oxford Street, Berkeley, CA 94720-3370, United States.
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Immune Responses to Dengue and Zika Viruses-Guidance for T Cell Vaccine Development. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2018; 15:ijerph15020385. [PMID: 29473899 PMCID: PMC5858454 DOI: 10.3390/ijerph15020385] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 02/19/2018] [Accepted: 02/19/2018] [Indexed: 02/01/2023]
Abstract
Despite numerous efforts to identify the molecular and cellular effectors of the adaptive immunity that induce a long-lasting immunity against dengue or Zika virus infection, the specific mechanisms underlying such protective immunity remain largely unknown. One of the major challenges lies in the high level of dengue virus (DENV) seroprevalence in areas where Zika virus (ZIKV) is circulating. In the context of such a pre-existing DENV immunity that can exacerbate ZIKV infection and disease, and given the lack of appropriate treatment for ZIKV infection, there is an urgent need to develop an efficient vaccine against DENV and ZIKV. Notably, whereas several ZIKV vaccine candidates are currently in clinical trials, all these vaccine candidates have been designed to induce neutralizing antibodies as the primary mechanism of immune protection. Given the difficulty to elicit simultaneously high levels of neutralizing antibodies against the different DENV serotypes, and the potential impact of pre-existing subneutralizing antibodies induced upon DENV infection or vaccination on ZIKV infection and disease, additional or alternative strategies to enhance vaccine efficacy, through T cell immunity, are now being considered. In this review, we summarize recent discoveries about cross-reactive B and T cell responses against DENV and ZIKV and propose guidelines for the development of safe and efficient T cell vaccines targeting both viruses.
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Budigi Y, Ong EZ, Robinson LN, Ong LC, Rowley KJ, Winnett A, Tan HC, Hobbie S, Shriver Z, Babcock GJ, Alonso S, Ooi EE. Neutralization of antibody-enhanced dengue infection by VIS513, a pan serotype reactive monoclonal antibody targeting domain III of the dengue E protein. PLoS Negl Trop Dis 2018; 12:e0006209. [PMID: 29425203 PMCID: PMC5823465 DOI: 10.1371/journal.pntd.0006209] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Revised: 02/22/2018] [Accepted: 01/04/2018] [Indexed: 01/13/2023] Open
Abstract
Dengue virus (DENV) infection imposes enormous health and economic burden worldwide with no approved treatment. Several small molecules, including lovastatin, celgosivir, balapiravir and chloroquine have been tested for potential anti-dengue activity in clinical trials; none of these have demonstrated a protective effect. Recently, based on identification and characterization of cross-serotype neutralizing antibodies, there is increasing attention on the potential for dengue immunotherapy. Here, we tested the ability of VIS513, an engineered cross-neutralizing humanized antibody targeting the DENV E protein domain III, to overcome antibody-enhanced infection and high but brief viremia, which are commonly encountered in dengue patients, in various in vitro and in vivo models. We observed that VIS513 efficiently neutralizes DENV at clinically relevant viral loads or in the presence of enhancing levels of DENV immune sera. Single therapeutic administration of VIS513 in mouse models of primary infection or lethal secondary antibody-enhanced infection, reduces DENV titers and protects from lethal infection. Finally, VIS513 administration does not readily lead to resistance, either in cell culture systems or in animal models of dengue infection. The findings suggest that rapid viral reduction during acute DENV infection with a monoclonal antibody is feasible.
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MESH Headings
- Animals
- Antibodies, Monoclonal/immunology
- Antibodies, Neutralizing/blood
- Antibodies, Neutralizing/immunology
- Antibodies, Viral/administration & dosage
- Antibodies, Viral/blood
- Antibodies, Viral/genetics
- Antibodies, Viral/immunology
- Antigens, Viral/chemistry
- Antigens, Viral/genetics
- Cell Line
- Chlorocebus aethiops
- Cross Reactions/immunology
- Dengue/immunology
- Dengue Virus/genetics
- Dengue Virus/immunology
- Dengue Virus/pathogenicity
- Disease Models, Animal
- Epitopes
- Female
- Humans
- Immune Sera
- Immunotherapy
- In Vitro Techniques
- Mice
- Models, Structural
- Mutation
- Neutralization Tests
- Protein Conformation
- Recombinant Proteins/chemistry
- Recombinant Proteins/genetics
- Recombinant Proteins/immunology
- Serogroup
- THP-1 Cells
- Vero Cells
- Viral Envelope Proteins/chemistry
- Viral Envelope Proteins/genetics
- Viral Envelope Proteins/immunology
- Viral Plaque Assay
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Affiliation(s)
- Yadunanda Budigi
- Visterra Singapore International Pte Ltd, Singapore, Singapore
- Infectious Diseases Interdisciplinary Research Group, Singapore-MIT Alliance for Research and Technology, Singapore, Singapore
- * E-mail: (YB); (EZO)
| | - Eugenia Z. Ong
- Experimental Therapeutics Centre, Agency for Science, Technology and Research, Singapore, Singapore
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore, Singapore
- * E-mail: (YB); (EZO)
| | - Luke N. Robinson
- Visterra Inc, Cambridge, Massachusetts, United States of America
| | - Li Ching Ong
- Department of Microbiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Kirk J. Rowley
- Visterra Inc, Cambridge, Massachusetts, United States of America
| | | | - Hwee Cheng Tan
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore, Singapore
| | - Sven Hobbie
- Visterra Singapore International Pte Ltd, Singapore, Singapore
| | - Zachary Shriver
- Visterra Inc, Cambridge, Massachusetts, United States of America
| | | | - Sylvie Alonso
- Department of Microbiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Eng Eong Ooi
- Infectious Diseases Interdisciplinary Research Group, Singapore-MIT Alliance for Research and Technology, Singapore, Singapore
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore, Singapore
- Department of Microbiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
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Ly MHP, Moi ML, Vu TBH, Tun MMN, Saunders T, Nguyen CN, Nguyen AKT, Nguyen HM, Dao TH, Pham DQ, Nguyen TTT, Le TQM, Hasebe F, Morita K. Dengue virus infection-enhancement activity in neutralizing antibodies of healthy adults before dengue season as determined by using FcγR-expressing cells. BMC Infect Dis 2018; 18:31. [PMID: 29321001 PMCID: PMC5763606 DOI: 10.1186/s12879-017-2894-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Accepted: 12/07/2017] [Indexed: 11/17/2022] Open
Abstract
Background Antibodies are critical responses to protect the host from dengue virus(DENV) infection. Antibodies target DENV by two pathologic mechanisms: virus neutralization and infection enhancement. In dengue patients, the absence of neutralizing activity in the presence of FcγR implies that infection-enhancing activity hampers the neutralizing activity of antibodies, which could potentially lead to symptomatic presentations and severe clinical outcomes. Methods A total of 100 pair serum samples from adult healthy volunteers were obtained during the dengue season in Ha Noi in 2015 for evaluation of neutralizing and infection-enhancing activity. Additionally, 20 serum samples from acute secondary DENV infection patients were also used as the patient group in this study. PRNT was performed on BHK cells and FcγR-expressing BHK cell lines for all serum samples. Results Out of 100 residents, positive neutralizing antibodies (N.A) were found in 44.23 and 76.92% for DENV-1; 38.46 and 75% for DENV-2; 19.23 and 15.38% for DENV-3; and 1.92 and 9.62% for DENV-4 for pre and post-dengue season respectively. The percentage of post-exposure residents having positive responses against single, two, or more than three DENV serotypes were 38.46, 44.23 and 15.38%, respectively. A total of 34 residents were DENV seropositive before the dengue season and these individuals demonstrated further elevation of IgG antibodies after the dengue season. At the end of the season, 18 residents were confirmed to be new asymptomatic DENV infection cases. In both groups, N.A titers determined on BHK cells were higher than that on FcγR-expressing BHK cells. In heterotypic N.A responses, N.A titers to the infecting serotype from the samples obtained from pre-exposure group were significantly higher than those of the patient group. However, fold enhancement to the infecting serotypes from the samples in the pre-exposure group was substantially lower as compared to that of the patient group. Conclusion Before and after the dengue season, serum samples from healthy volunteers demonstrated high levels of neutralizing antibodies and low or absence of infection-enhancement activity. The results suggest that while infection-enhancement activity hampers neutralizing activity of antibodies, high levels of DENV neutralizing antibodies set a critical threshold in facilitating the prevention of disease progression. Electronic supplementary material The online version of this article (10.1186/s12879-017-2894-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Minh Huong Phu Ly
- Department of Virology, Institute of Tropical Medicine, Nagasaki University, Sakamoto 1-12-4, Nagasaki, 852-8523, Japan.,Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.,Program for Nurturing Global Leaders in Tropical and Emerging Communicable Diseases, Nagasaki University, Nagasaki, Japan
| | - Meng Ling Moi
- Department of Virology, Institute of Tropical Medicine, Nagasaki University, Sakamoto 1-12-4, Nagasaki, 852-8523, Japan.
| | - Thi Bich Hau Vu
- Department of Virology, National Institute of Hygiene and Epidemiology, Hanoi, Viet Nam
| | - Mya Myat Ngwe Tun
- Department of Virology, Institute of Tropical Medicine, Nagasaki University, Sakamoto 1-12-4, Nagasaki, 852-8523, Japan
| | - Todd Saunders
- Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.,Program for Nurturing Global Leaders in Tropical and Emerging Communicable Diseases, Nagasaki University, Nagasaki, Japan
| | | | | | | | - Than Huu Dao
- Ha Noi Preventive Medicine Center, Hanoi, Viet Nam
| | - Do Quyen Pham
- Department of Virology, National Institute of Hygiene and Epidemiology, Hanoi, Viet Nam
| | - Thi Thu Thuy Nguyen
- Department of Virology, National Institute of Hygiene and Epidemiology, Hanoi, Viet Nam
| | - Thi Quynh Mai Le
- Department of Virology, National Institute of Hygiene and Epidemiology, Hanoi, Viet Nam
| | - Futoshi Hasebe
- Vietnam Research Station, Center for Infectious Disease Research in Asia and Africa, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
| | - Kouichi Morita
- Department of Virology, Institute of Tropical Medicine, Nagasaki University, Sakamoto 1-12-4, Nagasaki, 852-8523, Japan
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The Molecular Specificity of the Human Antibody Response to Dengue Virus Infections. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1062:63-76. [DOI: 10.1007/978-981-10-8727-1_5] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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68
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Immune status alters the probability of apparent illness due to dengue virus infection: Evidence from a pooled analysis across multiple cohort and cluster studies. PLoS Negl Trop Dis 2017; 11:e0005926. [PMID: 28953902 PMCID: PMC5633199 DOI: 10.1371/journal.pntd.0005926] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Revised: 10/09/2017] [Accepted: 09/02/2017] [Indexed: 11/24/2022] Open
Abstract
Dengue is an important vector-borne pathogen found across much of the world. Many factors complicate our understanding of the relationship between infection with one of the four dengue virus serotypes, and the observed incidence of disease. One of the factors is a large proportion of infections appear to result in no or few symptoms, while others result in severe infections. Estimates of the proportion of infections that result in no symptoms (inapparent) vary widely from 8% to 100%, depending on study and setting. To investigate the sources of variation of these estimates, we used a flexible framework to combine data from multiple cohort studies and cluster studies (follow-up around index cases). Building on previous observations that the immune status of individuals affects their probability of apparent disease, we estimated the probability of apparent disease among individuals with different exposure histories. In cohort studies mostly assessing infection in children, we estimated the proportion of infections that are apparent as 0.18 (95% Credible Interval, CI: 0.16, 0.20) for primary infections, 0.13 (95% CI: 0.05, 0.17) for individuals infected in the year following a first infection (cross-immune period), and 0.41 (95% CI: 0.36, 0.45) for those experiencing secondary infections after this first year. Estimates of the proportion of infections that are apparent from cluster studies were slightly higher than those from cohort studies for both primary and secondary infections, 0.22 (95% CI: 0.15, 0.29) and 0.57 (95% CI: 0.49, 0.68) respectively. We attempted to estimate the apparent proportion by serotype, but current published data were too limited to distinguish the presence or absence of serotype-specific differences. These estimates are critical for understanding dengue epidemiology. Most dengue data come from passive surveillance systems which not only miss most infections because they are asymptomatic and often underreported, but will also vary in sensitivity over time due to the interaction between previous incidence and the symptomatic proportion, as shown here. Nonetheless the underlying incidence of infection is critical to understanding susceptibility of the population and estimating the true burden of disease, key factors for effectively targeting interventions. The estimates shown here help clarify the link between past infection, observed disease, and current transmission intensity. Dengue disease severity is known to vary widely from the very severe to asymptomatic. There is a wide range of estimates of how many infections result in each of these outcomes. It is known that after a first infection the outcome of a second infection with a different serotype varies over time, but this has not been taken into account in these previous estimates. In this paper, we use modelling methods, combined with information from published dengue research in which individuals are followed over time, to estimate the proportion of infections that result in symptoms at different times after infection. We estimated the proportion of infections that are symptomatic for first infections as 0.18 (95% Credible Interval, CI: 0.16, 0.20), 0.13 (95% CI: 0.05, 0.17) for individuals infected in the year following a first infection and 0.41 (95% CI: 0.36, 0.45) for those experiencing secondary infections after this first year. The estimates here will help understand how cases relate to underlying transmission, which is vital for understanding how much of the population are susceptible to infection and for effectively targeting interventions.
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69
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Maier SB, Huang X, Massad E, Amaku M, Burattini MN, Greenhalgh D. Analysis of the optimal vaccination age for dengue in Brazil with a tetravalent dengue vaccine. Math Biosci 2017; 294:15-32. [PMID: 28935561 DOI: 10.1016/j.mbs.2017.09.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Revised: 05/18/2017] [Accepted: 09/11/2017] [Indexed: 02/06/2023]
Abstract
In this paper we study a mathematical model to analyse the optimal vaccination age against Dengue in Brazil. Data from Brazil are used to estimate the basic reproduction numbers for each of the four Dengue serotypes and then the optimal vaccination age is calculated using a method due to Hethcote [1]. The vaccine has different efficacies against each serotype. Vaccination that is too early is ineffective as individuals are protected by maternal antibodies but leaving vaccination until later may allow the disease to spread. First of all the optimal vaccination ages are calculated where there is just one serotype in circulation and then when there are multiple serotypes. The calculations are done using data both assuming constant vaccine efficacy and age-dependent vaccine efficacy against a given serotype. The multiple serotype calculations are repeated assuming that the first infection is a risky infection and that it is not (to model Dengue Antibody Enhancement). The calculations are then repeated when any third or fourth Dengue infections are asymptomatic, so that two Dengue infections with different serotypes provide effective permanent immunity. The calculations are also repeated when the age-dependent risk function (fitted to Brazilian data) is hospitalisation from Dengue and when it is mortality due to Dengue. We find a wide variety of optimal vaccination ages depending on both the serotypes in circulation and the assumptions of the model.
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Affiliation(s)
- Sandra B Maier
- Department of Mathematics and Statistics, University of Strathclyde, Glasgow G1 1XH, UK
| | - Xiao Huang
- Department of Mathematics and Statistics, University of Strathclyde, Glasgow G1 1XH, UK
| | - Eduardo Massad
- LIM01-Hospital de Clínicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brazil; Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - Marcos Amaku
- LIM01-Hospital de Clínicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Marcelo N Burattini
- LIM01-Hospital de Clínicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brazil; Hospital São Paulo, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brazil
| | - David Greenhalgh
- Department of Mathematics and Statistics, University of Strathclyde, Glasgow G1 1XH, UK.
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70
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Katzelnick LC, Harris E. Immune correlates of protection for dengue: State of the art and research agenda. Vaccine 2017; 35:4659-4669. [PMID: 28757058 PMCID: PMC5924688 DOI: 10.1016/j.vaccine.2017.07.045] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Revised: 07/04/2017] [Accepted: 07/13/2017] [Indexed: 01/15/2023]
Abstract
Dengue viruses (DENV1-4) are mosquito-borne flaviviruses estimated to cause up to ∼400 million infections and ∼100 million dengue cases each year. Factors that contribute to protection from and risk of dengue and severe dengue disease have been studied extensively but are still not fully understood. Results from Phase 3 vaccine efficacy trials have recently become available for one vaccine candidate, now licensed for use in several countries, and more Phase 2 and 3 studies of additional vaccine candidates are ongoing, making these issues all the more urgent and timely. At the "Summit on Dengue Immune Correlates of Protection", held in Annecy, France, on March 8-9, 2016, dengue experts from diverse fields came together to discuss the current understanding of the immune response to and protection from DENV infection and disease, identify key unanswered questions, discuss data on immune correlates and plans for comparison of results across assays/consortia, and propose a research agenda for investigation of dengue immune correlates, all in the context of both natural infection studies and vaccine trials.
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Affiliation(s)
- Leah C Katzelnick
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, Berkeley, CA 94720-3370, USA; Department of Biology, University of Florida, Gainesville, FL 32611, USA
| | - Eva Harris
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, Berkeley, CA 94720-3370, USA.
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71
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Abstract
The first approved dengue vaccine, CYD-TDV, a chimeric, live-attenuated, tetravalent dengue virus vaccine, was recently licensed in 13 countries, including Brazil. In light of recent vaccine approval, we modeled the cost-effectiveness of potential vaccination policies mathematically based on data from recent vaccine efficacy trials that indicated that vaccine efficacy was lower in seronegative individuals than in seropositive individuals. In our analysis, we investigated several vaccination programs, including routine vaccination, with various vaccine coverage levels and those with and without large catch-up campaigns. As it is unclear whether the vaccine protects against infection or just against disease, our model incorporated both direct and indirect effects of vaccination. We found that in the presence of vaccine-induced indirect protection, the cost-effectiveness of dengue vaccination decreased with increasing vaccine coverage levels because the marginal returns of herd immunity decreases with vaccine coverage. All routine dengue vaccination programs that we considered were cost-effective, reducing dengue incidence significantly. Specifically, a routine dengue vaccination of 9-year-olds would be cost-effective when the cost of vaccination per individual is less than $262. Furthermore, the combination of routine vaccination and large catch-up campaigns resulted in a greater reduction of dengue burden (by up to 93%) than routine vaccination alone, making it a cost-effective intervention as long as the cost per course of vaccination is $255 or less. Our results show that dengue vaccination would be cost-effective in Brazil even with a relatively low vaccine efficacy in seronegative individuals.
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Affiliation(s)
- Eunha Shim
- Department of Mathematics, Soongsil University, Seoul, Republic of Korea
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72
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Tsai WY, Lin HE, Wang WK. Complexity of Human Antibody Response to Dengue Virus: Implication for Vaccine Development. Front Microbiol 2017; 8:1372. [PMID: 28775720 PMCID: PMC5517401 DOI: 10.3389/fmicb.2017.01372] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Accepted: 07/06/2017] [Indexed: 01/21/2023] Open
Abstract
The four serotypes of dengue virus (DENV) are the leading cause of arboviral diseases in humans. Decades of efforts have made remarkable progress in dengue vaccine development. Despite the first dengue vaccine (dengvaxia from Sanofi Pasteur), a live-attenuated tetravalent chimeric yellow fever-dengue vaccine, has been licensed by several countries since 2016, its overall moderate efficacy (56.5–60.8%) in the presence of neutralizing antibodies during the Phase 2b and 3 trials, lower efficacy among dengue naïve compared with dengue experienced individuals, and increased risk of hospitalization among young children during the follow-up highlight the need for a better understanding of humoral responses after natural DENV infection. Recent studies of more than 300 human monoclonal antibodies (mAbs) against DENV have led to the discovery of several novel epitopes on the envelope protein recognized by potent neutralizing mAbs. This information together with in-depth studies on polyclonal sera and B-cells following natural DENV infection has tremendous implications for better immunogen design for a safe and effective dengue vaccine. This review outlines the progress in our understanding of mouse mAbs, human mAbs, and polyclonal sera against DENV envelope and precursor membrane proteins, two surface proteins involved in vaccine development, following natural infection; analyses of these discoveries have provided valuable insight into new strategies involving molecular technology to induce more potent neutralizing antibodies and less enhancing antibodies for next-generation dengue vaccine development.
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Affiliation(s)
- Wen-Yang Tsai
- Department of Tropical Medicine, Medical Microbiology and Pharmacology, John A. Burns School of Medicine, University of Hawaii at ManoaHonolulu, HI, United States
| | - Hong-En Lin
- Department of Tropical Medicine, Medical Microbiology and Pharmacology, John A. Burns School of Medicine, University of Hawaii at ManoaHonolulu, HI, United States
| | - Wei-Kung Wang
- Department of Tropical Medicine, Medical Microbiology and Pharmacology, John A. Burns School of Medicine, University of Hawaii at ManoaHonolulu, HI, United States
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73
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Achieving safe, effective, and durable Zika virus vaccines: lessons from dengue. THE LANCET. INFECTIOUS DISEASES 2017; 17:e378-e382. [PMID: 28711586 DOI: 10.1016/s1473-3099(17)30362-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Revised: 05/25/2017] [Accepted: 06/05/2017] [Indexed: 12/29/2022]
Abstract
Newly proposed candidate Zika virus vaccines might or might not succeed in raising safe, effective, and durable protection against human Zika virus infections or syndromes. Analyses of a clinically tested and licensed dengue vaccine that failed to protect seronegative individuals from breakthrough or enhanced dengue infections suggest that poor T-cell immunity might have contributed to protection failure. Because of the similarity of Zika and dengue viruses, an analogous unwanted outcome might occur with some Zika virus vaccine designs. A successful Zika virus vaccine requires challenge experiments that are done at long intervals after immunisation and that identify protection as the absence of viraemia and the absence of an anamnestic antibody response. T-cell immunity might be an essential component of safe, efficacious, and durable Zika virus vaccines.
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74
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Waggoner JJ, Gresh L, Mohamed-Hadley A, Balmaseda A, Soda KJ, Abeynayake J, Sahoo MK, Liu Y, Kuan G, Harris E, Pinsky BA. Characterization of Dengue Virus Infections Among Febrile Children Clinically Diagnosed With a Non-Dengue Illness, Managua, Nicaragua. J Infect Dis 2017; 215:1816-1823. [PMID: 28863466 PMCID: PMC5853235 DOI: 10.1093/infdis/jix195] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Accepted: 04/21/2017] [Indexed: 01/25/2023] Open
Abstract
Background We sought to characterize dengue virus (DENV) infections among febrile children enrolled in a pediatric cohort study who were clinically diagnosed with a non-dengue illness ("C cases"). Methods DENV infections were detected and viral load quantitated by real-time reverse transcription-polymerase chain reaction in C cases presenting between January 2007 and January 2013. Results One hundred forty-one of 2892 C cases (4.88%) tested positive for DENV. Of all febrile cases in the study, DENV-positive C cases accounted for an estimated 52.0% of patients with DENV viremia at presentation. Compared with previously detected, symptomatic dengue cases, DENV-positive C cases were significantly less likely to develop long-lasting humoral immune responses to DENV, as measured in healthy annual serum samples (79.7% vs 47.8%; P < .001). Humoral immunity was associated with viral load at presentation: 40 of 43 patients (93.0%) with a viral load ≥7.0 log10 copies/mL serum developed the expected rise in anti-DENV antibodies in annual samples versus 13 of 68 (19.1%) patients with a viral load below this level (P < .001). Conclusions Antibody responses to DENV-positive C cases differ from responses to classic symptomatic dengue. These findings have important implications for DENV transmission modeling, immunology, and epidemiologic surveillance.
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Affiliation(s)
- Jesse J Waggoner
- Department of Medicine, Division of Infectious Diseases and Geographic Medicine
| | | | - Alisha Mohamed-Hadley
- Department of Pathology, Stanford University School of Medicine, Stanford, California
| | - Angel Balmaseda
- National Virology Laboratory, Centro Nacional de Diagnóstico y Referencia, Ministry of Health
| | - K James Soda
- Department of Scientific Computing, Florida State University, Tallahassee
| | - Janaki Abeynayake
- Department of Pathology, Stanford University School of Medicine, Stanford, California
| | - Malaya K Sahoo
- Department of Pathology, Stanford University School of Medicine, Stanford, California
| | - Yuanyuan Liu
- Department of Pathology, Stanford University School of Medicine, Stanford, California
| | - Guillermina Kuan
- Centro de Salud Sócrates Flores Vivas, Ministry of Health, Managua, Nicaragua
| | - Eva Harris
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley
| | - Benjamin A Pinsky
- Department of Medicine, Division of Infectious Diseases and Geographic Medicine
- Department of Pathology, Stanford University School of Medicine, Stanford, California
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75
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Henein S, Swanstrom J, Byers AM, Moser JM, Shaik SF, Bonaparte M, Jackson N, Guy B, Baric R, de Silva AM. Dissecting Antibodies Induced by a Chimeric Yellow Fever-Dengue, Live-Attenuated, Tetravalent Dengue Vaccine (CYD-TDV) in Naive and Dengue-Exposed Individuals. J Infect Dis 2017; 215:351-358. [PMID: 27932620 DOI: 10.1093/infdis/jiw576] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Accepted: 11/21/2016] [Indexed: 11/13/2022] Open
Abstract
Sanofi Pasteur has developed a chimeric yellow fever-dengue, live-attenuated, tetravalent dengue vaccine (CYD-TDV) that is currently approved for use in several countries. In clinical trials, CYD-TDV was efficacious at reducing laboratory-confirmed cases of dengue disease. Efficacy varied by dengue virus (DENV) serotype and prevaccination dengue immune status. We compared the properties of antibodies in naive and DENV-exposed individuals who received CYD-TDV. We depleted specific populations of DENV-reactive antibodies from immune serum samples to estimate the contribution of serotype-cross-reactive and type-specific antibodies to neutralization. Subjects with no preexisting immunity to DENV developed neutralizing antibodies to all 4 serotypes of DENV. Further analysis demonstrated that DENV4 was mainly neutralized by type-specific antibodies whereas DENV1, DENV2, and DENV3 were mainly neutralized by serotype cross-reactive antibodies. When subjects with preexisting immunity to DENV were vaccinated, they developed higher levels of neutralizing antibodies than naive subjects who were vaccinated. In preimmune subjects, CYD-TDV boosted cross-reactive neutralizing antibodies while maintaining type-specific neutralizing antibodies acquired before vaccination. Our results demonstrate that the quality of neutralizing antibodies induced by CYD-TDV varies depending on DENV serotype and previous immune status. We discuss the implications of these results for understanding vaccine efficacy.
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Affiliation(s)
| | - Jesica Swanstrom
- Department of Epidemiology, Gillings School of Public Health, University of North Carolina, Chapel Hill
| | | | | | | | | | | | | | - Ralph Baric
- Department of Microbiology and Immunology and.,Department of Epidemiology, Gillings School of Public Health, University of North Carolina, Chapel Hill
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Whitehead SS, Durbin AP, Pierce KK, Elwood D, McElvany BD, Fraser EA, Carmolli MP, Tibery CM, Hynes NA, Jo M, Lovchik JM, Larsson CJ, Doty EA, Dickson DM, Luke CJ, Subbarao K, Diehl SA, Kirkpatrick BD. In a randomized trial, the live attenuated tetravalent dengue vaccine TV003 is well-tolerated and highly immunogenic in subjects with flavivirus exposure prior to vaccination. PLoS Negl Trop Dis 2017; 11:e0005584. [PMID: 28481883 PMCID: PMC5436874 DOI: 10.1371/journal.pntd.0005584] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 05/18/2017] [Accepted: 04/19/2017] [Indexed: 11/19/2022] Open
Abstract
Infection caused by the four serotypes of dengue virus (DENV-1-4) is a leading cause of mosquito-borne disease. Clinically-severe dengue disease is more common when secondary dengue infection occurs following prior infection with a heterologous dengue serotype. Other flaviviruses such as yellow fever virus, Japanese encephalitis virus, and Zika virus, can also elicit antibodies which are cross-reactive to DENV. As candidate dengue vaccines become available in endemic settings and for individuals who have received other flavivirus vaccines, it is important to examine vaccine safety and immunogenicity in these flavivirus-experienced populations. We performed a randomized, controlled trial of the National Institutes of Health live attenuated tetravalent dengue vaccine candidate (TV003) in fifty-eight individuals with prior exposure to flavivirus infection or vaccine. As in prior studies of this vaccine in flavivirus-naive volunteers, flavivirus-experienced subjects received two doses of vaccine six months apart and were followed closely for clinical events, laboratory changes, viremia, and neutralizing antibody titers. TV003 was well tolerated with few adverse events other than rash, which was predominately mild. Following one dose, 87% of vaccinees had an antibody response to all four serotypes (tetravalent response), suggesting a robust immune response. In addition, 76% of vaccinees were viremic; mean peak titers ranged from 0.68–1.1 log10 PFU/mL and did not differ by serotype. The second dose of TV003 was not associated with viremia, rash, or a sustained boost in antibody titers indicating that a single dose of the vaccine is likely sufficient to prevent viral replication and thus protect against disease. In comparison to the viremia and neutralizing antibody response elicited by TV003 in flavivirus-naïve subjects from prior studies, we found that subjects who were flavivirus-exposed prior to vaccination exhibited slightly higher DENV-3 viremia, higher neutralizing antibody titers to DENV-2, -3, and -4, and a higher tetravalent response frequency after TV003 administration. In summary, we demonstrate that the NIH tetravalent dengue vaccine TV003 is well-tolerated in flavivirus-experienced individuals and elicits robust post-vaccination neutralizing antibody titers. TRIAL REGISTRATION ClinicalTrials.gov NCT01506570.
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Affiliation(s)
- Stephen S. Whitehead
- Laboratory of Infectious Diseases, National Institutes of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Anna P. Durbin
- Center for Immunization Research, Johns Hopkins School of Public Health, Baltimore, Maryland; United States of America
| | - Kristen K. Pierce
- Vaccine Testing Center, Department of Medicine, University of Vermont Larner College of Medicine, Burlington, Vermont, United States of America
| | - Dan Elwood
- Center for Immunization Research, Johns Hopkins School of Public Health, Baltimore, Maryland; United States of America
| | - Benjamin D. McElvany
- Vaccine Testing Center, Department of Medicine, University of Vermont Larner College of Medicine, Burlington, Vermont, United States of America
| | - Ellen A. Fraser
- Vaccine Testing Center, Department of Medicine, University of Vermont Larner College of Medicine, Burlington, Vermont, United States of America
| | - Marya P. Carmolli
- Vaccine Testing Center, Department of Medicine, University of Vermont Larner College of Medicine, Burlington, Vermont, United States of America
| | - Cecilia M. Tibery
- Center for Immunization Research, Johns Hopkins School of Public Health, Baltimore, Maryland; United States of America
| | - Noreen A. Hynes
- Center for Immunization Research, Johns Hopkins School of Public Health, Baltimore, Maryland; United States of America
| | - Matthew Jo
- Center for Immunization Research, Johns Hopkins School of Public Health, Baltimore, Maryland; United States of America
| | - Janece M. Lovchik
- Center for Immunization Research, Johns Hopkins School of Public Health, Baltimore, Maryland; United States of America
| | - Catherine J. Larsson
- Vaccine Testing Center, Department of Medicine, University of Vermont Larner College of Medicine, Burlington, Vermont, United States of America
| | - Elena A. Doty
- Vaccine Testing Center, Department of Medicine, University of Vermont Larner College of Medicine, Burlington, Vermont, United States of America
| | - Dorothy M. Dickson
- Vaccine Testing Center, Department of Medicine, University of Vermont Larner College of Medicine, Burlington, Vermont, United States of America
| | - Catherine J. Luke
- Laboratory of Infectious Diseases, National Institutes of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Kanta Subbarao
- Laboratory of Infectious Diseases, National Institutes of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Sean A. Diehl
- Vaccine Testing Center, Department of Medicine, University of Vermont Larner College of Medicine, Burlington, Vermont, United States of America
| | - Beth D. Kirkpatrick
- Vaccine Testing Center, Department of Medicine, University of Vermont Larner College of Medicine, Burlington, Vermont, United States of America
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77
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Undurraga EA, Edillo FE, Erasmo JNV, Alera MTP, Yoon IK, Largo FM, Shepard DS. Disease Burden of Dengue in the Philippines: Adjusting for Underreporting by Comparing Active and Passive Dengue Surveillance in Punta Princesa, Cebu City. Am J Trop Med Hyg 2017; 96:887-898. [PMID: 28093542 PMCID: PMC5392638 DOI: 10.4269/ajtmh.16-0488] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Accepted: 11/29/2016] [Indexed: 02/05/2023] Open
Abstract
AbstractDengue virus (DENV) is a serious threat to public health. Having reliable estimates of the burden of dengue is important to inform policy and research, but surveillance systems are not designed to capture all symptomatic DENV infections. We derived the rate of reporting of dengue by comparing active surveillance of symptomatic DENV infections in a prospective community-based seroepidemiological cohort study (N = 1008) of acute febrile illness in Punta Princesa, Cebu City, Philippines, with passive surveillance data from the Cebu City Health Department. Febrile episodes detected in a weekly follow-up of participants were tested for serotype-specific DENV by hemi-nested reverse transcription-polymerase chain reaction (nested RT-PCR) and acute/convalescent blood samples tested by dengue IgM/IgG enzyme immunoassay. We estimated the burden of dengue in the Philippines in disability-adjusted life years (DALYs), and conducted a probabilistic sensitivity analysis using Monte-Carlo simulations to address uncertainty. The results showed a 21% cumulative reporting rate of symptomatic DENV infections, equivalent to an expansion factor of 4.7 (95% certainty level [CL]: 2.2-15.1). Based on surveillance data in the Philippines for 2010-2014, we estimated 794,255 annual dengue episodes (95% CL: 463,000-2,076,000) and a disease burden of 535 (95% CL: 380-994) DALYs per million population using age weights and time discounting and 997 (95% CL: 681-1,871) DALYs per million population without age and time adjustments. Dengue imposes a substantial burden in the Philippines; almost 10 times higher than estimated for rabies, about twice the burden of intestinal fluke infections, and about 10% of the burden of tuberculosis. Our estimates should inform policy makers and raise awareness among the public.
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Affiliation(s)
- Eduardo A. Undurraga
- Schneider Institutes for Health Policy, Heller School, Brandeis University, Waltham, MA
| | - Frances E. Edillo
- Department of Biology, University of San Carlos, Cebu City, Philippines
| | | | | | - In-Kyu Yoon
- Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
- Dengue Vaccine Initiative, International Vaccine Institute, Seoul, Republic of Korea
| | - Francisco M. Largo
- Department of Economics, University of San Carlos, Cebu City, Philippines
| | - Donald S. Shepard
- Schneider Institutes for Health Policy, Heller School, Brandeis University, Waltham, MA
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78
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Epidemiological Characteristics of Dengue Disease in Latin America and in the Caribbean: A Systematic Review of the Literature. J Trop Med 2017; 2017:8045435. [PMID: 28392806 PMCID: PMC5368385 DOI: 10.1155/2017/8045435] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Revised: 01/31/2017] [Accepted: 02/21/2017] [Indexed: 12/03/2022] Open
Abstract
Dengue, an important mosquito-borne virus transmitted mainly by Aedes aegypti, is a major public health issue in Latin America and the Caribbean. National epidemiological surveillance systems, usually based on passive detection of symptomatic cases, while underestimating the true burden of dengue disease, can provide valuable insight into disease trends and excess reporting and potential outbreaks. We carried out a systematic review of the literature to characterize the recent epidemiology of dengue disease in Latin America and the English-speaking and Hispanic Caribbean Islands. We identified 530 articles, 60 of which met criteria for inclusion. In general, dengue seropositivity across the region was high and increased with age. All four virus serotypes were reported to circulate in the region. These observations varied considerably between and within countries and over time, potentially due to climatic factors (temperature, rainfall, and relative humidity) and their effect on mosquito densities and differences in socioeconomic factors. This review provides important insight into the major epidemiological characteristics of dengue in distinct regions of Latin America and the Caribbean, allowing gaps in current knowledge and future research needs to be identified.
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79
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Katzelnick LC, Coloma J, Harris E. Dengue: knowledge gaps, unmet needs, and research priorities. THE LANCET. INFECTIOUS DISEASES 2017; 17:e88-e100. [PMID: 28185868 DOI: 10.1016/s1473-3099(16)30473-x] [Citation(s) in RCA: 117] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Revised: 08/29/2016] [Accepted: 10/18/2016] [Indexed: 01/09/2023]
Abstract
Dengue virus is a mosquito-borne pathogen that causes up to about 100 million cases of disease each year, placing a major public health, social, and economic burden on numerous low-income and middle-income countries. Major advances by investigators, vaccine developers, and affected communities are revealing new insights and enabling novel interventions and approaches to dengue prevention and control. Such research has highlighted further questions about both the basic understanding of dengue and efforts to develop new tools. In this report, the third in a Series on dengue, we discuss existing approaches to dengue diagnostics, disease prognosis, surveillance, and vector control in low-income and middle-income countries, as well as potential consequences of vaccine introduction. We also summarise current knowledge and recent insights into dengue epidemiology, immunology, and pathogenesis, and their implications for understanding natural infection and current and future vaccines.
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Affiliation(s)
- Leah C Katzelnick
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, CA, USA
| | - Josefina Coloma
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, CA, USA
| | - Eva Harris
- Division of Infectious Diseases and Vaccinology, School of Public Health, University of California, Berkeley, CA, USA.
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80
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Pang T, Mak TK, Gubler DJ. Prevention and control of dengue-the light at the end of the tunnel. THE LANCET. INFECTIOUS DISEASES 2017; 17:e79-e87. [PMID: 28185870 DOI: 10.1016/s1473-3099(16)30471-6] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Revised: 10/16/2016] [Accepted: 10/19/2016] [Indexed: 12/20/2022]
Abstract
Advances in the development of new dengue control tools, including vaccines and vector control, herald a new era of desperately needed dengue prevention and control. The burden of dengue has expanded for decades, and now affects more than 120 countries. Complex, large-scale global forces have and will continue to contribute to the expansion of dengue, including population growth, unplanned urbanisation, and suboptimal mosquito control in urban centres. Although no so-called magic bullets are available, there is new optimism following the first licensure of a dengue vaccine and other promising vaccine candidates, and the development of novel vector control interventions to help control dengue and other expanding mosquito-borne diseases such as Zika virus. Implementation of effective and sustainable immunisation programmes to complement existing methods will add complexity to the health systems of affected countries, which have varying levels of robustness and maturity. Long-term high prioritisation and adequate resources are needed. The way forward is full commitment to addressing a complex disease with a set of solutions integrating vaccination and vector control methods. A whole systems approach is thus needed to integrate these various approaches and strategies for controlling dengue within the goal of universal health coverage. The ultimate objective of these interventions will be to reduce the disease burden in a sustainable and equitable manner.
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Affiliation(s)
- Tikki Pang
- Lee Kuan Yew School of Public Policy, National University of Singapore, Singapore.
| | - Tippi K Mak
- Regional Health & Community Outreach Division, Health Promotion Board, Singapore
| | - Duane J Gubler
- Emerging Infectious Diseases Programme, Duke-NUS Medical School, National University of Singapore, Singapore
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81
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Shim E. Dengue Dynamics and Vaccine Cost-Effectiveness Analysis in the Philippines. Am J Trop Med Hyg 2016; 95:1137-1147. [PMID: 27601519 PMCID: PMC5094230 DOI: 10.4269/ajtmh.16-0194] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Accepted: 08/01/2016] [Indexed: 01/05/2023] Open
Abstract
Dengue is one of the most problematic vector-borne diseases in the Philippines, with an estimated 842,867 cases resulting in medical costs of $345 million U.S. dollars annually. In December 2015, the first dengue vaccine, known as chimeric yellow fever virus-dengue virus tetravalent dengue vaccine, was approved for use in the Philippines and is given to children 9 years of age. To estimate the cost-effectiveness of dengue vaccination in the Philippines, we developed an age-structured model of dengue transmission and vaccination. Using our model, we compared two vaccination scenarios entailing routine vaccination programs both with and without catch-up vaccination. Our results indicate that the higher the cost of vaccination, the less cost-effective the dengue vaccination program. With the current dengue vaccination program that vaccinates children 9 years of age, dengue vaccination is cost-effective for vaccination costs up to $70 from a health-care perspective and up to $75 from a societal perspective. Under a favorable scenario consisting of 1 year of catch-up vaccinations that target children 9-15 years of age, followed by regular vaccination of 9-year-old children, vaccination is cost-effective at costs up to $72 from a health-care perspective and up to $78 from a societal perspective. In general, dengue vaccination is expected to reduce the incidence of both dengue fever and dengue hemorrhagic fever /dengue shock syndrome. Our results demonstrate that even at relatively low vaccine efficacies, age-targeted vaccination may still be cost-effective provided the vaccination cost is sufficiently low.
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Affiliation(s)
- Eunha Shim
- Department of Mathematics, Soongsil University, Seoul, Republic of Korea
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82
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Abstract
In a Perspective, Jacqueline Deeen discusses challenges in balancing the individual and population risks and benefits for CYD-TDV (Dengvaxia), the first available dengue vaccine.
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83
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Chan KR, Wang X, Saron WAA, Gan ES, Tan HC, Mok DZL, Zhang SLX, Lee YH, Liang C, Wijaya L, Ghosh S, Cheung YB, Tannenbaum SR, Abraham SN, St John AL, Low JGH, Ooi EE. Cross-reactive antibodies enhance live attenuated virus infection for increased immunogenicity. Nat Microbiol 2016; 1:16164. [PMID: 27642668 PMCID: PMC7097525 DOI: 10.1038/nmicrobiol.2016.164] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Accepted: 08/08/2016] [Indexed: 01/10/2023]
Abstract
Vaccination has achieved remarkable successes in the control of childhood viral diseases. To control emerging infections, however, vaccines will need to be delivered to older individuals who, unlike infants, probably have had prior infection or vaccination with related viruses and thus have cross-reactive antibodies against the vaccines. Whether and how these cross-reactive antibodies impact live attenuated vaccination efficacy is unclear. Using an open-label randomized trial design, we show that subjects with a specific range of cross-reactive antibody titres from a prior inactivated Japanese encephalitis vaccination enhanced yellow fever (YF) immunogenicity upon YF vaccination. Enhancing titres of cross-reactive antibodies prolonged YF vaccine viraemia, provoked greater pro-inflammatory responses, and induced adhesion molecules intrinsic to the activating Fc-receptor signalling pathway, namely immune semaphorins, facilitating immune cell interactions and trafficking. Our findings clinically demonstrate antibody-enhanced infection and suggest that vaccine efficacy could be improved by exploiting cross-reactive antibodies.
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Affiliation(s)
- Kuan Rong Chan
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore 169857
| | - Xiaohui Wang
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore 169857
| | - Wilfried A A Saron
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore 169857
| | - Esther Shuyi Gan
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore 169857
| | - Hwee Cheng Tan
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore 169857
| | - Darren Z L Mok
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117597
| | - Summer Li-Xin Zhang
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore 169857
| | - Yie Hou Lee
- Interdisciplinary Research Group in Infectious Diseases, Singapore-MIT Alliance for Research & Technology (SMART), Singapore 138602.,KK Research Centre, KK Women's and Children's Hospital, Singapore 229899
| | - Cui Liang
- Interdisciplinary Research Group in Infectious Diseases, Singapore-MIT Alliance for Research & Technology (SMART), Singapore 138602
| | - Limin Wijaya
- Department of Infectious Diseases, Singapore General Hospital, Singapore 169856
| | - Sujoy Ghosh
- Centre for Computational Biology, Duke-NUS Medical School, Singapore 169857
| | - Yin Bun Cheung
- Center for Quantitative Medicine, Duke-NUS Medical School, Singapore 169857.,Department for International Health, University of Tampere, 33100 Finland
| | - Steven R Tannenbaum
- Interdisciplinary Research Group in Infectious Diseases, Singapore-MIT Alliance for Research & Technology (SMART), Singapore 138602.,Department of Biological Engineering and Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Soman N Abraham
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore 169857.,Department of Immunology and the Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina 27710, USA
| | - Ashley L St John
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore 169857
| | - Jenny G H Low
- Department of Infectious Diseases, Singapore General Hospital, Singapore 169856
| | - Eng Eong Ooi
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore 169857.,Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117597.,Interdisciplinary Research Group in Infectious Diseases, Singapore-MIT Alliance for Research & Technology (SMART), Singapore 138602
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84
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Ferguson NM, Rodríguez-Barraquer I, Dorigatti I, Mier-Y-Teran-Romero L, Laydon DJ, Cummings DAT. Benefits and risks of the Sanofi-Pasteur dengue vaccine: Modeling optimal deployment. Science 2016; 353:1033-1036. [PMID: 27701113 PMCID: PMC5268127 DOI: 10.1126/science.aaf9590] [Citation(s) in RCA: 159] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Accepted: 07/29/2016] [Indexed: 01/08/2023]
Abstract
The first approved dengue vaccine has now been licensed in six countries. We propose that this live attenuated vaccine acts like a silent natural infection in priming or boosting host immunity. A transmission dynamic model incorporating this hypothesis fits recent clinical trial data well and predicts that vaccine effectiveness depends strongly on the age group vaccinated and local transmission intensity. Vaccination in low-transmission settings may increase the incidence of more severe "secondary-like" infection and, thus, the numbers hospitalized for dengue. In moderate transmission settings, we predict positive impacts overall but increased risks of hospitalization with dengue disease for individuals who are vaccinated when seronegative. However, in high-transmission settings, vaccination benefits both the whole population and seronegative recipients. Our analysis can help inform policy-makers evaluating this and other candidate dengue vaccines.
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Affiliation(s)
- Neil M Ferguson
- MRC Centre for Outbreak Analysis and Modelling, School of Public Health, Imperial College London, Norfolk Place, London W2 1PG, UK.
| | - Isabel Rodríguez-Barraquer
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe Street, Baltimore, MD 21205, USA
| | - Ilaria Dorigatti
- MRC Centre for Outbreak Analysis and Modelling, School of Public Health, Imperial College London, Norfolk Place, London W2 1PG, UK
| | - Luis Mier-Y-Teran-Romero
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe Street, Baltimore, MD 21205, USA
| | | | - Derek A T Cummings
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe Street, Baltimore, MD 21205, USA. Department of Biology and Emerging Pathogens Institute, University of Florida, Post Office Box 100009, Gainesville, FL 32610, USA
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85
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Abstract
Dengue is widespread throughout the tropics and local spatial variation in dengue virus transmission is strongly influenced by rainfall, temperature, urbanization and distribution of the principal mosquito vector Aedes aegypti. Currently, endemic dengue virus transmission is reported in the Eastern Mediterranean, American, South-East Asian, Western Pacific and African regions, whereas sporadic local transmission has been reported in Europe and the United States as the result of virus introduction to areas where Ae. aegypti and Aedes albopictus, a secondary vector, occur. The global burden of the disease is not well known, but its epidemiological patterns are alarming for both human health and the global economy. Dengue has been identified as a disease of the future owing to trends toward increased urbanization, scarce water supplies and, possibly, environmental change. According to the WHO, dengue control is technically feasible with coordinated international technical and financial support for national programmes. This Primer provides a general overview on dengue, covering epidemiology, control, disease mechanisms, diagnosis, treatment and research priorities.
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Affiliation(s)
- Maria G Guzman
- Institute of Tropical Medicine 'Pedro Kouri', PAHO/WHO Collaborating Center for the Study of Dengue and its Vector, Autopista Novia del Mediodia, Km 6 1/2, Havana 11400, Cuba
| | - Duane J Gubler
- Program in Emerging Infectious Diseases, Duke-NUS Graduate Medical School, Singapore
| | - Alienys Izquierdo
- Institute of Tropical Medicine 'Pedro Kouri', PAHO/WHO Collaborating Center for the Study of Dengue and its Vector, Autopista Novia del Mediodia, Km 6 1/2, Havana 11400, Cuba
| | - Eric Martinez
- Institute of Tropical Medicine 'Pedro Kouri', PAHO/WHO Collaborating Center for the Study of Dengue and its Vector, Autopista Novia del Mediodia, Km 6 1/2, Havana 11400, Cuba
| | - Scott B Halstead
- Department of Preventive Medicine and Biometrics, Uniformed Services University of the Health Sciences, Bethesda, Maryland, USA
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86
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Dengue Virus Envelope Dimer Epitope Monoclonal Antibodies Isolated from Dengue Patients Are Protective against Zika Virus. mBio 2016; 7:mBio.01123-16. [PMID: 27435464 PMCID: PMC4958264 DOI: 10.1128/mbio.01123-16] [Citation(s) in RCA: 185] [Impact Index Per Article: 23.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
UNLABELLED Zika virus (ZIKV) is a mosquito-borne flavivirus responsible for thousands of cases of severe fetal malformations and neurological disease since its introduction to Brazil in 2013. Antibodies to flaviviruses can be protective, resulting in lifelong immunity to reinfection by homologous virus. However, cross-reactive antibodies can complicate flavivirus diagnostics and promote more severe disease, as noted after serial dengue virus (DENV) infections. The endemic circulation of DENV in South America and elsewhere raises concerns that preexisting flavivirus immunity may modulate ZIKV disease and transmission potential. Here, we report on the ability of human monoclonal antibodies and immune sera derived from dengue patients to neutralize contemporary epidemic ZIKV strains. We demonstrate that a class of human monoclonal antibodies isolated from DENV patients neutralizes ZIKV in cell culture and is protective in a lethal murine model. We also tested a large panel of convalescent-phase immune sera from humans exposed to primary and repeat DENV infection. Although ZIKV is most closely related to DENV compared to other human-pathogenic flaviviruses, most DENV immune sera (73%) failed to neutralize ZIKV, while others had low (50% effective concentration [EC50], <1:100 serum dilution; 18%) or moderate to high (EC50, >1:100 serum dilution; 9%) levels of cross-neutralizing antibodies. Our results establish that ZIKV and DENV share epitopes that are targeted by neutralizing, protective human antibodies. The availability of potently neutralizing human monoclonal antibodies provides an immunotherapeutic approach to control life-threatening ZIKV infection and also points to the possibility of repurposing DENV vaccines to induce cross-protective immunity to ZIKV. IMPORTANCE ZIKV is an emerging arbovirus that has been associated with severe neurological birth defects and fetal loss in pregnant women and Guillain-Barré syndrome in adults. Currently, there is no vaccine or therapeutic for ZIKV. The identification of a class of antibodies (envelope dimer epitope 1 [EDE1]) that potently neutralizes ZIKV in addition to all four DENV serotypes points to a potential immunotherapeutic to combat ZIKV. This is especially salient given the precedent of antibody therapy to treat pregnant women infected with other viruses associated with microcephaly, such as cytomegalovirus and rubella virus. Furthermore, the identification of a functionally conserved epitope between ZIKV and DENV raises the possibility that a vaccine may be able to elicit neutralizing antibodies against both viruses.
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87
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Velumani S, Toh YX, Balasingam S, Archuleta S, Leo YS, Gan VC, Thein TL, Wilder-Smith A, Fink K. Low antibody titers 5 years after vaccination with the CYD-TDV dengue vaccine in both pre-immune and naïve vaccinees. Hum Vaccin Immunother 2016; 12:1265-73. [PMID: 26889737 DOI: 10.1080/21645515.2015.1126012] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Globally, dengue virus (DENV) is one of the most widespread vector-borne viruses. Dengue disease affects populations in endemic areas and, increasingly, tourists who travel to these countries, but there is currently no approved vaccine for dengue. A phase 3 efficacy trial with Sanofi-Pasteur's recombinant, live-attenuated, tetravalent dengue vaccine (CYD-TDV) conducted in South East Asia showed an overall efficacy of 56% against virologically confirmed dengue infections of any severity and any of the 4 serotypes, but the long-term protection of the vaccine has yet to be demonstrated. To address longevity of antibody titers and B cell memory, we recalled study participants from an earlier CYD immunogenicity study (Phase 2) conducted in Singapore that enrolled healthy volunteers in the year 2009. Depending on the age group, 57-84% of the participants initially generated a neutralizing antibody titer ≥ 10 to all 4 DENV serotypes 28 d after the third and final dose. We observed very low antibody titers in blood samples collected from 23 vaccinees 5 y after the first dose, particularly titers of antibodies binding to virus particles compared with those binding to recombinant E protein. The in vivo efficacy of plasma antibodies against DENV-2 challenge was also tested in a mouse model, which found that only 2 out of 23 samples were able to reduce viremia. Although the sample size is too small for general conclusions, dengue immune memory after vaccination with CYD-TDV appears relatively low.
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Affiliation(s)
- Sumathy Velumani
- a Singapore Immunology Network, Agency for Science, Technology (A*STAR) , Singapore , Singapore
| | - Ying Xiu Toh
- a Singapore Immunology Network, Agency for Science, Technology (A*STAR) , Singapore , Singapore
| | - Shobana Balasingam
- b Lee Kong Chian School of Medicine, Nanyang Technological University , Singapore , Singapore
| | - Sophia Archuleta
- c Division of Infectious Diseases, University Medicine Cluster, National University Hospital , Singapore , Singapore.,d Department of Medicine , Yong Loo Lin School of Medicine, National University of Singapore , Singapore
| | - Yee Sin Leo
- e Communicable Disease Center, Institute of Infectious Disease and Epidemiology, Tan Tock Seng Hospital , Singapore , Singapore.,f Yong Loo Lin School of Medicine, National University of Singapore , Singapore , Singapore
| | - Victor C Gan
- e Communicable Disease Center, Institute of Infectious Disease and Epidemiology, Tan Tock Seng Hospital , Singapore , Singapore
| | - Tun Linn Thein
- e Communicable Disease Center, Institute of Infectious Disease and Epidemiology, Tan Tock Seng Hospital , Singapore , Singapore
| | - Annelies Wilder-Smith
- b Lee Kong Chian School of Medicine, Nanyang Technological University , Singapore , Singapore
| | - Katja Fink
- a Singapore Immunology Network, Agency for Science, Technology (A*STAR) , Singapore , Singapore.,b Lee Kong Chian School of Medicine, Nanyang Technological University , Singapore , Singapore
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88
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The Epidemiology, Virology and Clinical Findings of Dengue Virus Infections in a Cohort of Indonesian Adults in Western Java. PLoS Negl Trop Dis 2016; 10:e0004390. [PMID: 26872216 PMCID: PMC4752237 DOI: 10.1371/journal.pntd.0004390] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Accepted: 12/23/2015] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Dengue has emerged as one of the most important infectious diseases in the last five decades. Evidence indicates the expansion of dengue virus endemic areas and consequently the exponential increase of dengue virus infections across the subtropics. The clinical manifestations of dengue virus infection include sudden fever, rash, headache, myalgia and in more serious cases, spontaneous bleeding. These manifestations occur in children as well as in adults. Defining the epidemiology of dengue in a given area is critical to understanding the disease and devising effective public health strategies. METHODOLOGY/PRINCIPAL FINDINGS Here, we report the results from a prospective cohort study of 4380 adults in West Java, Indonesia, from 2000-2004 and 2006-2009. A total of 2167 febrile episodes were documented and dengue virus infections were confirmed by RT-PCR or serology in 268 cases (12.4%). The proportion ranged from 7.6 to 41.8% each year. The overall incidence rate of symptomatic dengue virus infections was 17.3 cases/1,000 person years and between September 2006 and April 2008 asymptomatic infections were 2.6 times more frequent than symptomatic infections. According to the 1997 WHO classification guidelines, there were 210 dengue fever cases, 53 dengue hemorrhagic fever cases (including one dengue shock syndrome case) and five unclassified cases. Evidence for sequential dengue virus infections was seen in six subjects. All four dengue virus serotypes circulated most years. Inapparent dengue virus infections were predominantly associated with DENV-4 infections. CONCLUSIONS/SIGNIFICANCE Dengue virus was responsible for a significant percentage of febrile illnesses in an adult population in West Java, Indonesia, and this percentage varied from year to year. The observed incidence rate during the study period was 43 times higher than the reported national or provincial rates during the same time period. A wide range of clinical severity was observed with most infections resulting in asymptomatic disease. The circulation of all four serotypes of dengue virus was observed in most years of the study.
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89
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Halstead SB, Russell PK. Protective and immunological behavior of chimeric yellow fever dengue vaccine. Vaccine 2016; 34:1643-7. [PMID: 26873054 DOI: 10.1016/j.vaccine.2016.02.004] [Citation(s) in RCA: 122] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Revised: 01/25/2016] [Accepted: 02/01/2016] [Indexed: 10/22/2022]
Abstract
Clinical observations from the third year of the Sanofi Pasteur chimeric yellow fever dengue tetravalent vaccine (CYD) trials document both protection and vaccination-enhanced dengue disease among vaccine recipients. Children who were 5 years-old or younger when vaccinated experienced a DENV disease resulting in hospitalization at 5 times the rate of controls. On closer inspection, hospitalized cases among vaccinated seropositives, those at highest risk to hospitalized disease accompanying a dengue virus (DENV) infection, were greatly reduced by vaccination. But, seronegative individuals of all ages after being vaccinated were only modestly protected from mild to moderate disease throughout the entire observation period despite developing neutralizing antibodies at high rates. Applying a simple epidemiological model to the data, vaccinated seronegative individuals of all ages were at increased risk of developing hospitalized disease during a subsequent wild type DENV infection. The etiology of disease in placebo and vaccinated children resulting in hospitalization during a DENV infection, while clinically similar are of different origin. The implications of the observed mixture of DENV protection and enhanced disease in CYD vaccinees are discussed.
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Affiliation(s)
- Scott B Halstead
- Private Consultant, 5824 Edson Lane, North Bethesda, MD 20852, USA.
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90
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Incomplete Protection against Dengue Virus Type 2 Re-infection in Peru. PLoS Negl Trop Dis 2016; 10:e0004398. [PMID: 26848841 PMCID: PMC4746126 DOI: 10.1371/journal.pntd.0004398] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Accepted: 12/29/2015] [Indexed: 12/27/2022] Open
Abstract
Background Nearly half of the world’s population is at risk for dengue, yet no licensed vaccine or anti-viral drug is currently available. Dengue is caused by any of four dengue virus serotypes (DENV-1 through DENV-4), and infection by a DENV serotype is assumed to provide life-long protection against re-infection by that serotype. We investigated the validity of this fundamental assumption during a large dengue epidemic caused by DENV-2 in Iquitos, Peru, in 2010–2011, 15 years after the first outbreak of DENV-2 in the region. Methodology/Principal Findings We estimated the age-dependent prevalence of serotype-specific DENV antibodies from longitudinal cohort studies conducted between 1993 and 2010. During the 2010–2011 epidemic, active dengue cases were identified through active community- and clinic-based febrile surveillance studies, and acute inapparent DENV infections were identified through contact tracing studies. Based on the age-specific prevalence of DENV-2 neutralizing antibodies, the age distribution of DENV-2 cases was markedly older than expected. Homologous protection was estimated at 35.1% (95% confidence interval: 0%–65.2%). At the individual level, pre-existing DENV-2 antibodies were associated with an incomplete reduction in the frequency of symptoms. Among dengue cases, 43% (26/66) exhibited elevated DENV-2 neutralizing antibody titers for years prior to infection, compared with 76% (13/17) of inapparent infections (age-adjusted odds ratio: 4.2; 95% confidence interval: 1.1–17.7). Conclusions/Significance Our data indicate that protection from homologous DENV re-infection may be incomplete in some circumstances, which provides context for the limited vaccine efficacy against DENV-2 in recent trials. Further studies are warranted to confirm this phenomenon and to evaluate the potential role of incomplete homologous protection in DENV transmission dynamics. Dengue is a mosquito-borne viral illness that imposes a tremendous public health burden on tropical and sub-tropical regions. An estimated 390 million infections occur globally each year, and up to 4 billion people are at risk. Dengue is caused by four dengue virus (DENV) serotypes (DENV-1 to DENV-4). Infection with any DENV can lead to a range of disease outcomes, from mild febrile illness to severe, hemorrhagic manifestations and death. Infection by one serotype has been assume to provide complete and lifelong protection against re-infection by the same serotype, and to our knowledge, instances of re-infection by the same serotype have not been rigorously documented. However, few long-term studies have been conducted in such a way that re-infection by the same serotype could be observed, if it did in fact occur. Our study provides evidence that re-infection may occur in certain circumstances. We draw from data collected during a 2010–2011 DENV-2 epidemic in northeastern Peru, 15 years after the initial DENV-2 outbreak in the region. This finding has significant implications for our understanding of dengue epidemiology and for dengue vaccine formulation, which may need to consider multiple genotypes of each serotype. Data from other long-term dengue epidemiology studies should be analyzed to determine if homologous re-infection is a more widespread phenomenon.
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91
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Alera MT, Srikiatkhachorn A, Velasco JM, Tac-An IA, Lago CB, Clapham HE, Fernandez S, Levy JW, Thaisomboonsuk B, Klungthong C, Macareo LR, Nisalak A, Hermann L, Villa D, Yoon IK. Incidence of Dengue Virus Infection in Adults and Children in a Prospective Longitudinal Cohort in the Philippines. PLoS Negl Trop Dis 2016; 10:e0004337. [PMID: 26845762 PMCID: PMC4742283 DOI: 10.1371/journal.pntd.0004337] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Accepted: 12/07/2015] [Indexed: 11/19/2022] Open
Abstract
Background The mean age of dengue has been increasing in some but not all countries. We sought to determine the incidence of dengue virus (DENV) infection in adults and children in a prospective cohort study in the Philippines where dengue is hyperendemic. Methodology/Principal Findings A prospective cohort of subjects ≥6 months old in Cebu City, Philippines, underwent active community-based surveillance for acute febrile illnesses by weekly contact. Fever history within the prior seven days was evaluated with an acute illness visit followed by 2, 5, and 8-day, and 3-week convalescent visits. Blood was collected at the acute and 3-week visits. Scheduled visits took place at enrolment and 12 months that included blood collections. Acute samples were tested by DENV PCR and acute/convalescent samples by DENV IgM/IgG ELISA to identify symptomatic infections. Enrolment and 12-month samples were tested by DENV hemagglutination inhibition (HAI) assay to identify subclinical infections. Of 1,008 enrolled subjects, 854 completed all study activities at 12 months per-protocol undergoing 868 person-years of surveillance. The incidence of symptomatic and subclinical infections was 1.62 and 7.03 per 100 person-years, respectively. However, in subjects >15 years old, only one symptomatic infection occurred whereas 27 subclinical infections were identified. DENV HAI seroprevalence increased sharply with age with baseline multitypic HAIs associated with fewer symptomatic infections. Using a catalytic model, the historical infection rate among dengue naïve individuals was estimated to be high at 11–22%/year. Conclusions/Significance In this hyperendemic area with high seroprevalence of multitypic DENV HAIs in adults, symptomatic dengue rarely occurred in individuals older than 15 years. Our findings demonstrate that dengue is primarily a pediatric disease in areas with high force of infection. However, the average age of dengue could increase if force of infection decreases over time, as is occurring in some hyperendemic countries such as Thailand. The average age of dengue has been increasing in some but not all dengue endemic countries. To investigate the age pattern of dengue in people of all ages ≥6 months old, a prospective community-based cohort study was undertaken in Cebu City, Philippines where dengue virus has been circulating for many decades. Active surveillance for acute fevers was performed, and acute/convalescent blood samples were tested for evidence of symptomatic dengue. Blood was also collected at enrolment and one year later, and tested serologically to identify subclinical infections. Overall, 1.62 symptomatic and 7.03 subclinical infections per 100 person-years of surveillance were detected. Among people older than 15 years, only one symptomatic dengue case occurred while 27 subclinical infections were identified. By analyzing age-specific dengue serology data, the historical infection rate among people with no prior dengue virus infection was found to be high at around 11–22% per year. Our results show that dengue is primarily a childhood disease in endemic settings where the historical infection rate has been high. However, the average age of dengue could increase if the infection rate decreases over time as is happening in some endemic countries like Thailand.
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Affiliation(s)
- Maria Theresa Alera
- Philippines-AFRIMS Virology Research Unit, CAP Building, Cebu City, Philippines
| | - Anon Srikiatkhachorn
- Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - John Mark Velasco
- Philippines-AFRIMS Virology Research Unit, CAP Building, Cebu City, Philippines
| | | | - Catherine B Lago
- Philippines-AFRIMS Virology Research Unit, CAP Building, Cebu City, Philippines
| | - Hannah E Clapham
- Department of Epidemiology, Johns Hopkins School of Public Health, Baltimore, Maryland, United States of America
| | - Stefan Fernandez
- Department of Virology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | - Jens W Levy
- Department of Virology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | - Butsaya Thaisomboonsuk
- Department of Virology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | - Chonticha Klungthong
- Department of Virology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | - Louis R Macareo
- Department of Virology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | - Ananda Nisalak
- Department of Virology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | - Laura Hermann
- Department of Virology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
- Department of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Daisy Villa
- Cebu City Health Department, Cebu City, Philippines
| | - In-Kyu Yoon
- Department of Virology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
- Dengue Vaccine Initiative, International Vaccine Institute, Seoul, Korea
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92
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Saadatian-Elahi M, Horstick O, Breiman RF, Gessner BD, Gubler DJ, Louis J, Parashar UD, Tapia R, Picot V, Zinsou JA, Nelson CB. Beyond efficacy: The full public health impact of vaccines. Vaccine 2016; 34:1139-47. [PMID: 26808648 DOI: 10.1016/j.vaccine.2016.01.021] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Revised: 12/21/2015] [Accepted: 01/12/2016] [Indexed: 01/31/2023]
Abstract
There is an active discussion in the public health community on how to assess and incorporate, in addition to safety and measures of protective efficacy, the full public health value of preventive vaccines into the evidence-based decision-making process of vaccine licensure and recommendations for public health use. The conference "Beyond efficacy: the full public health impact of vaccines in addition to efficacy measures in trials" held in Annecy, France (June 22-24, 2015) has addressed this issue and provided recommendations on how to better capture the whole public health impact of vaccines. Using key examples, the expert group stressed that we are in the midst of a new paradigm in vaccine evaluation, where all aspects of public health value of vaccines beyond efficacy should be evaluated. To yield a wider scope of vaccine benefits, additional measures such as vaccine preventable disease incidence, overall efficacy and other outcomes such as under-five mortality or non-etiologically confirmed clinical syndromes should be assessed in addition to traditional efficacy or effectiveness measurements. Dynamic modelling and the use of probe studies should also be considered to provide additional insight to the full public health value of a vaccine. The use of burden reduction and conditional licensure of vaccines based on collection of outcome results should be considered by regulatory agencies.
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Affiliation(s)
- Mitra Saadatian-Elahi
- Hospices Civils de Lyon, Groupement Hospitalier Edouard Herriot, 5 Place d'Arsonval, 69437 Lyon Cedex 03, France.
| | - Olaf Horstick
- Institute of Public Health, University of Heidelberg, Germany
| | - Robert F Breiman
- Emory Global Health Institute, Emory University, Atlanta, GA, United States
| | | | - Duane J Gubler
- Duke-NUS Graduate Medical School, 8 College Road, Singapore 169857, Singapore
| | - Jacques Louis
- Fondation Mérieux, 17 rue Bourgelat, 69002 Lyon, France
| | - Umesh D Parashar
- National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, GA, United States
| | | | | | - Jean-Antoine Zinsou
- Sanofi Pasteur, Vaccination Policy Department, 2 Avenue du Pont Pasteur, 69367 Lyon Cedex 07, France
| | - Christopher B Nelson
- Sanofi Pasteur, Vaccination Policy Department, 2 Avenue du Pont Pasteur, 69367 Lyon Cedex 07, France
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93
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Guy B, Lang J, Saville M, Jackson N. Vaccination Against Dengue: Challenges and Current Developments. Annu Rev Med 2016; 67:387-404. [DOI: 10.1146/annurev-med-091014-090848] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Bruno Guy
- Research and Development, Sanofi Pasteur, 69007 Lyon, France;
| | - Jean Lang
- Research and Development, Sanofi Pasteur, 69007 Lyon, France;
| | - Melanie Saville
- Research and Development, Sanofi Pasteur, 69007 Lyon, France;
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94
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Neutralizing antibody titers against dengue virus correlate with protection from symptomatic infection in a longitudinal cohort. Proc Natl Acad Sci U S A 2016; 113:728-33. [PMID: 26729879 DOI: 10.1073/pnas.1522136113] [Citation(s) in RCA: 135] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
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.
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95
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Clapham HE, Rodriguez-Barraquer I, Azman AS, Althouse BM, Salje H, Gibbons RV, Rothman AL, Jarman RG, Nisalak A, Thaisomboonsuk B, Kalayanarooj S, Nimmannitya S, Vaughn DW, Green S, Yoon IK, Cummings DAT. Dengue Virus (DENV) Neutralizing Antibody Kinetics in Children After Symptomatic Primary and Postprimary DENV Infection. J Infect Dis 2015; 213:1428-35. [PMID: 26704615 DOI: 10.1093/infdis/jiv759] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Accepted: 12/14/2015] [Indexed: 12/25/2022] Open
Abstract
The immune response to dengue virus (DENV) infection is complex and not fully understood. Using longitudinal data from 181 children with dengue in Thailand who were followed for up to 3 years, we describe neutralizing antibody kinetics following symptomatic DENV infection. We observed that antibody titers varied by serotype, homotypic vs heterotypic responses, and primary versus postprimary infections. The rates of change in antibody titers over time varied between primary and postprimary responses. For primary infections, titers increased from convalescence to 6 months. By comparing homotypic and heterotypic antibody titers, we saw an increase in type specificity from convalescence to 6 months for primary DENV3 infections but not primary DENV1 infections. In postprimary cases, there was a decrease in titers from convalescence up until 6 months after infection. Beginning 1 year after both primary and postprimary infections, there was evidence of increasing antibody titers, with greater increases in children with lower titers, suggesting that antibody titers were boosted due to infection and that higher levels of neutralizing antibody may be more likely to confer a sterilizing immune response. These findings may help to model virus transmission dynamics and provide baseline data to support the development of vaccines and therapeutics.
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Affiliation(s)
- Hannah E Clapham
- Department of Epidemiology, Johns Hopkins School of Public Health, Baltimore, Maryland
| | | | - Andrew S Azman
- Department of Epidemiology, Johns Hopkins School of Public Health, Baltimore, Maryland
| | - Benjamin M Althouse
- Institute for Disease Modeling, Bellevue, Washington Santa Fe Institute, Las Cruces, New Mexico New Mexico State University, Las Cruces, New Mexico
| | - Henrik Salje
- Department of Epidemiology, Johns Hopkins School of Public Health, Baltimore, Maryland
| | | | | | - Richard G Jarman
- Department of Virology, Armed Forces Research Institute of Medical Science
| | - Ananda Nisalak
- Department of Virology, Armed Forces Research Institute of Medical Science
| | | | | | | | - David W Vaughn
- Department of Virology, Armed Forces Research Institute of Medical Science
| | - Sharone Green
- Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester
| | - In-Kyu Yoon
- Dengue Vaccine Initiative, International Vaccine Institute, Seoul, Korea
| | - Derek A T Cummings
- Department of Epidemiology, Johns Hopkins School of Public Health, Baltimore, Maryland Department of Biology, University of Florida, Gainesville Emerging Pathogens Institute, University of Florida, Gainesville
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96
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Martínez-Vega RA, Danis-Lozano R, Díaz-Quijano FA, Velasco-Hernández J, Santos-Luna R, Román-Pérez S, Kuri-Morales P, Ramos-Castañeda J. Peridomestic Infection as a Determining Factor of Dengue Transmission. PLoS Negl Trop Dis 2015; 9:e0004296. [PMID: 26671573 PMCID: PMC4684393 DOI: 10.1371/journal.pntd.0004296] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2015] [Accepted: 11/20/2015] [Indexed: 11/18/2022] Open
Abstract
Background The study of endemic dengue transmission is essential for proposing alternatives to impact its burden. The traditional paradigm establishes that transmission starts around cases, but there are few studies that determine the risk. Methods To assess the association between the peridomestic dengue infection and the exposure to a dengue index case (IC), a cohort was carried out in two Mexican endemic communities. People cohabitating with IC or living within a 50-meter radius (exposed cohort) and subjects of areas with no ICs in a 200-meter radius (unexposed cohort) were included. Results Exposure was associated with DENV infection in cohabitants (PRa 3.55; 95%CI 2.37–5.31) or neighbors (PRa 1.82; 95%CI 1.29–2.58). Age, location, toilets with no direct water discharge, families with children younger than 5 and the House Index, were associated with infection. Families with older than 13 were associated with a decreased frequency. After a month since the IC fever onset, the infection incidence was not influenced by exposure to an IC or vector density; it was influenced by the local seasonal behavior of dengue and the age. Additionally, we found asymptomatic infections accounted for 60% and a greater age was a protective factor for the presence of symptoms (RR 0.98; 95%CI 0.97–0.99). Conclusion The evidence suggests that dengue endemic transmission in these locations is initially peridomestic, around an infected subject who may be asymptomatic due to demographic structure and endemicity, and it is influenced by other characteristics of the individual, the neighborhood and the location. Once the transmission chain has been established, dengue spreads in the community probably by the adults who, despite being the group with lower infection frequency, mostly suffer asymptomatic infections and have higher mobility. This scenario complicates the opportunity and the effectiveness of control programs and highlights the need to apply multiple measures for dengue control. The study of dengue transmission is essential for proposing alternatives to diminish the cases and the cost of dengue treatment and control. The traditional paradigm establishes that transmission chain starts around a case, but there are few studies that determine the risk, therefore, we studied if to live around a dengue case increases the risk to get infected by Dengue virus. We interviewed and took blood samples from people cohabitating with dengue cases and neighbors in two Mexican communities, to compare we interviewed and took blood samples from subjects of areas without dengue cases in these communities. We found that people cohabitating and neighbors had more risk to get infected. Younger and older person, the workers, families with children younger than 5, houses with toilets with no direct water discharge, and areas with more mosquitoes, also had increased infection risk until one month after the fever onset of dengue case. After this month the frequency of dengue infections was only influenced by the seasonal behavior of dengue and the age of the subjects. Also, we found that 60% of infections are asymptomatic and older people have less risk to develop symptoms. This study suggests that dengue transmission in these locations is initially peridomestic, around the houses of infected subject who may be asymptomatic (without symptoms), and it is influenced by other characteristics of the individual, the neighborhood and the community. After this peridomestic transmission, dengue spreads in the community probably by adults who mostly suffer asymptomatic infections and have higher mobility, which complicates the application and affects the results of vector control programs.
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Affiliation(s)
- Ruth Aralí Martínez-Vega
- Escuela de Medicina, Universidad de Santander, Bucaramanga, Santander, Colombia
- Centro de Investigaciones sobre Enfermedades Infecciosas, Instituto Nacional de Salud Pública, Cuernavaca, Morelos, México
- Organización Latinoamericana para el Fomento de la Investigación en Salud, Bucaramanga, Santander, Colombia
| | - Rogelio Danis-Lozano
- Departamento de Control de Vectores, Instituto Nacional de Salud Pública, Tapachula, Chiapas, México
| | | | - Jorge Velasco-Hernández
- Universidad Nacional Autónoma de Mexico-Juriquilla, Santiago de Querétaro, Querétaro, México
| | - René Santos-Luna
- Subdirección de Geografía Médica y Sistemas, Instituto Nacional de Salud Pública, Cuernavaca, Morelos, México
| | - Susana Román-Pérez
- Subdirección de Geografía Médica y Sistemas, Instituto Nacional de Salud Pública, Cuernavaca, Morelos, México
| | - Pablo Kuri-Morales
- Facultad de Medicina, Universidad Nacional Autónoma de México, México D.F., México
| | - José Ramos-Castañeda
- Centro de Investigaciones sobre Enfermedades Infecciosas, Instituto Nacional de Salud Pública, Cuernavaca, Morelos, México
- Center for Tropical Diseases, University of Texas-Medical Branch, Galveston, Texas, United States of America
- * E-mail:
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97
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Guy B, Jackson N. Dengue vaccine: hypotheses to understand CYD-TDV-induced protection. Nat Rev Microbiol 2015; 14:45-54. [PMID: 26639777 DOI: 10.1038/nrmicro.2015.2] [Citation(s) in RCA: 139] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Dengue virus (DENV) is a human pathogen with a large impact on public health. Although no vaccine against DENV is currently licensed, a recombinant vaccine - chimeric yellow fever virus-DENV tetravalent dengue vaccine (CYD-TDV) - has shown efficacy against symptomatic dengue disease in two recent Phase III clinical trials. Safety observations were also recently reported for these trials. In this Opinion article, we review the data from recent vaccine clinical trials and discuss the putative mechanisms behind the observed efficacy of the vaccine against different forms of the disease, focusing on the interactions between the infecting virus, pre-existing host immunity and vaccine-induced immune responses.
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Affiliation(s)
- Bruno Guy
- Sanofi Pasteur, Research &Development, 2 Avenue du Pont Pasteur, 69007 Lyon, France
| | - Nicholas Jackson
- Sanofi Pasteur, Research &Development, 2 Avenue du Pont Pasteur, 69007 Lyon, France
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98
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Whitehead SS. Development of TV003/TV005, a single dose, highly immunogenic live attenuated dengue vaccine; what makes this vaccine different from the Sanofi-Pasteur CYD™ vaccine? Expert Rev Vaccines 2015; 15:509-17. [PMID: 26559731 PMCID: PMC4956407 DOI: 10.1586/14760584.2016.1115727] [Citation(s) in RCA: 108] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Dengue is caused by four serotype-distinct dengue viruses (DENVs), and developing a multivalent vaccine against dengue has not been straightforward since partial immunity to DENV may predispose to more severe disease upon subsequent DENV infection. The vaccine that is furthest along in development is CYD™, a live attenuated tetravalent vaccine (LATV) produced by Sanofi Pasteur. Although the multi-dose vaccine demonstrated protection against severe dengue, its overall efficacy was limited by DENV serotype, serostatus at vaccination, region and age. The National Institute of Allergy and Infectious Diseases has developed the LATV dengue vaccines TV003/TV005. A single dose of either TV003 or TV005 induced seroconversion to four DENV serotypes in 74-92% (TV003) and 90% (TV005) of flavivirus seronegative adults and elicited near-sterilizing immunity to a second dose of vaccine administered 6-12 months later. The important differences in the structure, infectivity and immune responses to TV003/TV005 are compared with CYD™.
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Affiliation(s)
- Stephen S Whitehead
- a Laboratory of Infectious Diseases , NIAID, National Institutes of Health , Bethesda , MD , USA
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99
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Development of the Sanofi Pasteur tetravalent dengue vaccine: One more step forward. Vaccine 2015; 33:7100-11. [DOI: 10.1016/j.vaccine.2015.09.108] [Citation(s) in RCA: 114] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Revised: 09/03/2015] [Accepted: 09/07/2015] [Indexed: 01/06/2023]
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100
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New insights into the immunopathology and control of dengue virus infection. Nat Rev Immunol 2015; 15:745-59. [DOI: 10.1038/nri3916] [Citation(s) in RCA: 232] [Impact Index Per Article: 25.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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