1
|
Mancini MV, Murdochy SM, Bilgo E, Ant TH, Gingell D, Gnambani EJ, Failloux AB, Diabate A, Sinkins SP. Wolbachia strain wAlbB shows favourable characteristics for dengue control use in Aedes aegypti from Burkina Faso. Environ Microbiol 2024; 26:e16588. [PMID: 38450576 DOI: 10.1111/1462-2920.16588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Accepted: 01/23/2024] [Indexed: 03/08/2024]
Abstract
Dengue represents an increasing public health burden worldwide. In Africa, underreporting and misdiagnosis often mask its true epidemiology, and dengue is likely to be both more widespread than reported data suggest and increasing in incidence and distribution. Wolbachia-based dengue control is underway in Asia and the Americas but has not to date been deployed in Africa. Due to the genetic heterogeneity of African Aedes aegypti populations and the complexity of the host-symbiont interactions, characterization of key parameters of Wolbachia-carrying mosquitoes is paramount for determining the potential of the system as a control tool for dengue in Africa. The wAlbB Wolbachia strain was stably introduced into an African Ae. aegypti population by introgression, and showed high intracellular density in whole bodies and different mosquito tissues; high intracellular density was also maintained following larval rearing at high temperatures. No effect on the adult lifespan induced by Wolbachia presence was detected. Moreover, the ability of this strain to strongly inhibit DENV-2 dissemination and transmission in the host was also demonstrated in the African background. Our findings suggest the potential of harnessing Wolbachia for dengue control for African populations of Ae. aegypti.
Collapse
Affiliation(s)
- Maria Vittoria Mancini
- MRC-University of Glasgow Centre for Virus Research, Glasgow, UK
- Department of Biology and Biotechnology, University of Pavia, Pavia, Italy
| | | | - Etienne Bilgo
- Institut de Recherche en Sciences de la Santé, Direction Régionale de l'Ouest, Dioulasso, Burkina Faso
- Institut National de Santé Publique/Centre Muraz, Dioulasso, Burkina Faso
| | - Thomas H Ant
- MRC-University of Glasgow Centre for Virus Research, Glasgow, UK
| | - Daniel Gingell
- MRC-University of Glasgow Centre for Virus Research, Glasgow, UK
| | - Edounou Jacques Gnambani
- Institut de Recherche en Sciences de la Santé, Direction Régionale de l'Ouest, Dioulasso, Burkina Faso
- Institut National de Santé Publique/Centre Muraz, Dioulasso, Burkina Faso
| | - Anna-Bella Failloux
- Institut Pasteur, Université Paris Cité, Arboviruses and Insect Vectors Unit, Paris, France
| | - Abdoulaye Diabate
- Institut de Recherche en Sciences de la Santé, Direction Régionale de l'Ouest, Dioulasso, Burkina Faso
- Institut National de Santé Publique/Centre Muraz, Dioulasso, Burkina Faso
| | - Steven P Sinkins
- MRC-University of Glasgow Centre for Virus Research, Glasgow, UK
| |
Collapse
|
2
|
Malik S, Ahsan O, Mumtaz H, Tahir Khan M, Sah R, Waheed Y. Tracing down the Updates on Dengue Virus-Molecular Biology, Antivirals, and Vaccine Strategies. Vaccines (Basel) 2023; 11:1328. [PMID: 37631896 PMCID: PMC10458802 DOI: 10.3390/vaccines11081328] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Revised: 07/28/2023] [Accepted: 08/02/2023] [Indexed: 08/29/2023] Open
Abstract
BACKGROUND Nearly half of the world is at risk of developing dengue infection. Dengue virus is the causative agent behind this public healthcare concern. Millions of dengue cases are reported every year, leading to thousands of deaths. The scientific community is working to develop effective therapeutic strategies in the form of vaccines and antiviral drugs against dengue. METHODS In this review, a methodological approach has been used to gather data from the past five years to include the latest developments against the dengue virus. RESULTS Different therapeutics and antiviral targets against the dengue virus are at different stages of development, but none have been approved by the FDA. Moreover, various vaccination strategies have also been discussed, including attenuated virus vaccines, recombinant subunit vaccines, viral vector vaccines, DNA vaccines, nanotechnology, and plant-based vaccines, which are used to develop effective vaccines for the dengue virus. Many dengue vaccines pass the initial phases of evaluation, but only two vaccines have been approved for public use. DENGVAXIA is the only FDA-approved vaccine against all four stereotypes of the dengue virus, but it is licensed for use only in individuals 6-16 years of age with laboratory-confirmed previous dengue infection and living in endemic countries. Takeda is the second vaccine approved for use in the European Union, the United Kingdom, Brazil, Argentina, Indonesia, and Thailand. It produced sustained antibody responses against all four serotypes of dengue virus, regardless of previous exposure and dosing schedule. Other dengue vaccine candidates at different stages of development are TV-003/005, TDENV PIV, V180, and some DNA vaccines. CONCLUSION There is a need to put more effort into developing effective vaccines and therapeutics for dengue, as already approved vaccines and therapeutics have limitations. DENGVAXIA is approved for use in children and teenagers who are 6-16 years of age and have confirmed dengue infection, while Takeda is approved for use in certain countries, and it has withdrawn its application for FDA approval.
Collapse
Affiliation(s)
- Shiza Malik
- Bridging Health Foundation, Rawalpindi 46000, Pakistan
| | - Omar Ahsan
- Department of Medicine, Foundation University Medical College, Foundation University Islamabad, Islamabad 44000, Pakistan
| | - Hassan Mumtaz
- Innovation, Implementation, and Partnership Unit, Association for Social Development, Islamabad 44000, Pakistan
- Health Services Academy, Islamabad 44000, Pakistan
| | - Muhammad Tahir Khan
- Institute of Molecular Biology and Biotechnology (IMBB), University of Lahore, 1KM Defence Road, Lahore 58810, Pakistan
- Zhongjing Research and Industrialization Institute of Chinese Medicine, Zhongguancun Scientific Park, Meixi, Nanyang 473006, China
| | - Ranjit Sah
- Department of Microbiology, Tribhuvan University Teaching Hospital, Institute of Medicine, Kathmandu 44600, Nepal
- Department of Microbiology, Dr. D. Y. Patil Medical College, Hospital and Research Centre, Dr. D. Y. Patil Vidyapeeth, Pune 411018, Maharashtra, India
- Department of Public Health Dentistry, Dr. D.Y. Patil Dental College and Hospital, Dr. D.Y. Patil Vidyapeeth, Pune 411018, Maharashtra, India
| | - Yasir Waheed
- Office of Research, Innovation and Commercialization (ORIC), Shaheed Zulfiqar Ali Bhutto Medical University (SZABMU), Islamabad 44000, Pakistan
- Gilbert and Rose-Marie Chagoury School of Medicine, Lebanese American University, Byblos 1401, Lebanon
| |
Collapse
|
3
|
Abd El-Wahab EW, Elfiky KSR, Ghanem MA, Shatat HZ. Assessment of dengue virus threat to blood safety and community health: A single center study in northern Egypt. J Virus Erad 2022; 8:100077. [PMID: 35795869 PMCID: PMC9251716 DOI: 10.1016/j.jve.2022.100077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 06/11/2022] [Accepted: 06/16/2022] [Indexed: 11/16/2022] Open
Abstract
Background The risk of transfusion transmitted dengue (DENV) is increasingly recognized and poses a risk to blood safety as well as spreading into non-immune communities. Objectives To determine dengue serological profile, environmental risk, knowledge, and preventive measures among blood donors in a national blood bank in northern Egypt. Methods A total of 500 blood donors were enrolled into this study between June and September 2018. Socio-demographic and medical data were collected using a predesigned questionnaire. Blood samples were screened for anti-DENV IgM, anti-DENV IgG and non-structural protein 1 antigen (DENV-NS1 antigen). Results History of past dengue exposure was identified in 10.2% of blood donors. No samples (0.0%) tested positive for anti-DENV IgG, IgM or NS1 antigen. At the time of blood donation, no individuals had any symptoms suggestive of a dengue-related illness. Dengue exposure strongly correlated with travel to the Kingdom of Saudi Arabia (KSA), Sudan and the El-Quseir outbreak area in Egypt. Knowledge of dengue and prevention methods was found to be substantially deficient, and the relatively higher level of knowledge among exposed donors did not translate into appropriate preventative measures. Conclusions Our risk assessment shows the impact of travel on DENV exposure and highlights its potential threat to disease spread in Egypt. Dengue awareness programs are urgently needed for effective prevention of transmission.
Collapse
Affiliation(s)
- Ekram W Abd El-Wahab
- Tropical Health Department, High Institute of Public Health, Alexandria University, 21561, Alexandria, Egypt
| | - Karima S R Elfiky
- Fellow of Tropical Health Department, High Institute of Public Health, Alexandria University, 21561, Alexandria, Egypt.,Specialist at Kafr El-Dawar Public Hospital Blood Bank, Behira, Egypt
| | - Mohamed A Ghanem
- Director of Kafr El-Dawar Public Hospital Blood Bank, Behira, Egypt
| | - Hanan Z Shatat
- Tropical Health Department, High Institute of Public Health, Alexandria University, 21561, Alexandria, Egypt
| |
Collapse
|
4
|
Shah MM, Ndenga BA, Mutuku FM, Vu DM, Grossi-Soyster EN, Okuta V, Ronga CO, Chebii PK, Maina P, Jembe Z, Bosire CM, Amugongo JS, Sahoo MK, Huang C, Weber J, Edgerton SV, Hortion J, Bennett SN, Pinsky BA, LaBeaud AD. High Dengue Burden and Circulation of 4 Virus Serotypes among Children with Undifferentiated Fever, Kenya, 2014-2017. Emerg Infect Dis 2021; 26:2638-2650. [PMID: 33079035 PMCID: PMC7588514 DOI: 10.3201/eid2611.200960] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Little is known about the extent and serotypes of dengue viruses circulating in Africa. We evaluated the presence of dengue viremia during 4 years of surveillance (2014–2017) among children with febrile illness in Kenya. Acutely ill febrile children were recruited from 4 clinical sites in western and coastal Kenya, and 1,022 participant samples were tested by using a highly sensitive real-time reverse transcription PCR. A complete case analysis with genomic sequencing and phylogenetic analyses was conducted to characterize the presence of dengue viremia among participants during 2014–2017. Dengue viremia was detected in 41.9% (361/862) of outpatient children who had undifferentiated febrile illness in Kenya. Of children with confirmed dengue viremia, 51.5% (150/291) had malaria parasitemia. All 4 dengue virus serotypes were detected, and phylogenetic analyses showed several viruses from novel lineages. Our results suggests high levels of dengue virus infection among children with undifferentiated febrile illness in Kenya.
Collapse
|
5
|
Warnes CM, Santacruz-Sanmartín E, Bustos Carrillo F, Vélez ID. Surveillance and Epidemiology of Dengue in Medellín, Colombia from 2009 to 2017. Am J Trop Med Hyg 2021; 104:1719-1728. [PMID: 33755586 PMCID: PMC8103481 DOI: 10.4269/ajtmh.19-0728] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Accepted: 01/22/2021] [Indexed: 11/07/2022] Open
Abstract
Dengue is the most prevalent arthropod-borne viral disease in humans, primarily transmitted by the Aedes aegypti mosquito. We conducted a descriptive analysis of dengue cases from 2009 to 2017 in Medellín, Colombia, using data available from the Secretariat of Health. We analyzed the burden of outbreak years on the healthcare system, risk of cases exhibiting severe illness, potential disease surveillance problems, gender and age as risk factors, and spatiotemporal patterns of disease occurrence. Our data consisted of 50,083 cases, separated based on whether they were diagnostic test negative, diagnostic test positive (primarily IgM ELISA), clinically confirmed, epidemiologically linked, or probable. We used dengue incidence to analyze epidemiological trends between our study years, related to human movement patterns, between gender and age-groups, and spatiotemporally. We used risk to analyze the severity of dengue cases between the study years. We identified human movement could contributed to dengue spread, and male individuals (incidence rate: 0.86; 95% CI: 0.76-0.96) and individuals younger than 15 years (incidence rate: 1.24; 95% CI: 1.13-1.34) have higher incidence of dengue and located critical parts of the city where dengue incidence was high. Analysis was limited by participant diagnostic information, data concerning circulating strains, and a lack of phylogenetic information. Understanding the characteristics of dengue is a fundamental part of improving the health outcomes of at-risk populations. This analysis will be useful to support studies and initiatives to counteract dengue and provide context to the surveillance data collected by the health authorities in Medellín.
Collapse
Affiliation(s)
- Colin M. Warnes
- Programa de Estudio y Control de Enfermedades Tropicales (PECET), Universidad de Antioquia, Medellín, Colombia
| | - Eduardo Santacruz-Sanmartín
- Programa de Estudio y Control de Enfermedades Tropicales (PECET), Universidad de Antioquia, Medellín, Colombia
| | | | - Iván Darío Vélez
- Programa de Estudio y Control de Enfermedades Tropicales (PECET), Universidad de Antioquia, Medellín, Colombia
| |
Collapse
|
6
|
Ullah MA, Araf Y, Faruqui NA, Mowna SA, Prium DH, Sarkar B. Dengue Outbreak is a Global Recurrent Crisis: Review of the Literature. ELECTRONIC JOURNAL OF GENERAL MEDICINE 2020. [DOI: 10.29333/ejgm/8948] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
7
|
Charette M, Berrang-Ford L, Coomes O, Llanos-Cuentas EA, Cárcamo C, Kulkarni M, Harper SL. Dengue Incidence and Sociodemographic Conditions in Pucallpa, Peruvian Amazon: What Role for Modification of the Dengue-Temperature Relationship? Am J Trop Med Hyg 2019; 102:180-190. [PMID: 31701852 DOI: 10.4269/ajtmh.19-0033] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Dengue is a climate-sensitive disease with an increasing global burden. Although the relationship between meteorological conditions and dengue incidence is well established, less is known about the modifying nature of sociodemographic variables on that relationship. We assess the strength and direction of sociodemographic effect modification of the temperature-dengue relationship in the second largest city of the Peruvian Amazon to identify populations that may have heightened vulnerability to dengue under varying climate conditions. We used weekly dengue counts and averaged meteorological variables to evaluate the association between disease incidence, meteorological exposures, and sociodemographic effect modifiers (gender, age, and district) in negative binomial regression models. District was included to consider geographical effect modification. We found that being a young child or elderly, being female, and living in the district of Manantay increased dengue's incidence rate ratio (IRR) as a result of 1°C increase in weekly mean temperature (IRR = 2.99, 95% CI: 1.99-4.50 for women less than 5 years old and IRR = 2.86, 95% CI: = 1.93-4.22 for women older than 65 years, both estimates valid for the rainy season). The effect of temperature on dengue depended on season, with stronger effects during rainy seasons. Sociodemographic variables can provide options for intervention to mitigate health impacts with a changing climate. Our results indicate that patterns of baseline risk between regions and sociodemographic conditions can differ substantially from trends in climate sensitivity. These results challenge the assumption that the distribution of climate change impacts will be patterned similarly to existing social gradients in health.
Collapse
Affiliation(s)
- Margot Charette
- Department of Geography, McGill University, Montreal, Canada
| | - Lea Berrang-Ford
- Priestley International Centre for Climate, University of Leeds, Leeds, United Kingdom
| | - Oliver Coomes
- Department of Geography, McGill University, Montreal, Canada
| | | | - César Cárcamo
- School of Public Health and Administration, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Manisha Kulkarni
- School of Epidemiology, Public Health and Preventive Medicine, University of Ottawa, Ottawa, Canada
| | | |
Collapse
|
8
|
Consensus and uncertainty in the geographic range of Aedes aegypti and Aedes albopictus in the contiguous United States: Multi-model assessment and synthesis. PLoS Comput Biol 2019; 15:e1007369. [PMID: 31600194 PMCID: PMC6786520 DOI: 10.1371/journal.pcbi.1007369] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Accepted: 09/02/2019] [Indexed: 11/23/2022] Open
Abstract
Aedes (Stegomyia) aegypti (L.) and Ae. (Stegomyia) albopictus (Skuse) mosquitoes can transmit dengue, chikungunya, yellow fever, and Zika viruses. Limited surveillance has led to uncertainty regarding the geographic ranges of these vectors globally, and particularly in regions at the present-day margins of habitat suitability such as the contiguous United States. Empirical habitat suitability models based on environmental conditions can augment surveillance gaps to describe the estimated potential species ranges, but model accuracy is unclear. We identified previously published regional and global habitat suitability models for Ae. aegypti (n = 6) and Ae. albopictus (n = 8) for which adequate information was available to reproduce the models for the contiguous U.S. Using a training subset of recently updated county-level surveillance records of Ae. aegypti and Ae. albopictus and records of counties conducting surveillance, we constructed accuracy-weighted, probabilistic ensemble models from these base models. To assess accuracy and uncertainty we compared individual and ensemble model predictions of species presence or absence to both training and testing data. The ensemble models were among the most accurate and also provided calibrated probabilities of presence for each species. The quantitative probabilistic framework enabled identification of areas with high uncertainty and model bias across the U.S. where improved models or additional data could be most beneficial. The results may be of immediate utility for counties considering surveillance and control programs for Ae. aegypti and Ae. albopictus. Moreover, the assessment framework can drive future efforts to provide validated quantitative estimates to support these programs at local, national, and international scales. Aedes aegypti and Ae. albopictus mosquitoes can transmit dengue, chikungunya, yellow fever, and Zika viruses, yet because of limited data the edges of the geographic range of these important species remain uncertain. We assessed numerous previously published model-based estimates of the range of these mosquitoes in the United States and combined those models to produce calibrated estimates of the probability of finding each mosquito in each county. Comparing these estimates to county-level data, we found that there are areas of substantial uncertainty and specific areas where model-based predictions do not align well with available data. The results provide specific information that can help guide national- or state-level efforts to monitor and control Ae. aegypti and Ae. albopictus. Beyond the specific findings, this approach to leveraging limited data and multiple quantitative models can be employed in other settings to better characterize the distribution of these species and other medically important vectors globally.
Collapse
|
9
|
Dhinakaran SR, Mathew N, Munusamy S. Synergistic terpene combinations as larvicides against the dengue vector Aedes aegypti Linn. Drug Dev Res 2019; 80:791-799. [PMID: 31241777 DOI: 10.1002/ddr.21560] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Revised: 06/06/2019] [Accepted: 06/13/2019] [Indexed: 12/23/2022]
Abstract
Most of the essential oils (EO) known for mosquitocidal activity contain terpenes as part of their chemical constituents. In this study, four monoterpenes namely γ-terpinene (T), R-(+)-limonene (L), carvacrol (C), and trans-anethole (A) were screened against late third instar Aedes aegypti Linn. larvae singly and in combination to find out the synergistic interaction. The monoterpenes γ-terpinene, R-(+)-limonene, trans-anethole, and carvacrol showed larvicidal activity with LC50 values of 9.76, 11.88, 50.19, 48.57 ppm and LC90 values of 16.99, 17.78, 65.21, 75.02 ppm, respectively for Ae. aegypti when tested individually. Prepared binary combinations at LC20 values and studied the synergistic interactions based on cotoxicity factor (CTF) and found that all the binary combinations showed synergistic interactions (CTF > 20). Further, the binary (1:1), ternary (1:1:1), and quaternary (1:1:1:1) terpene combinations on equal weight basis were prepared, evaluated against Ae. aegypti larvae and synergistic interactions were studied by Wadley's method. Among the eight combinations two combinations viz. LC (LC50 10.42 ppm) and LA (LC50 11.86 ppm) were showing synergistic interactions (R > 1.5) and others were exhibiting additive effect (1.5 ≥ R > 0.5) and none of the combinations showed antagonism (R < 0.5). Among the two methods used the Wadley's method found suitable when combinations were made on an equal weight basis. The two binary combinations found in this study are promising synergistic mixtures which has scope in designing mosquito larvicidal EOs by enriching the EOs with terpenes or by producing EO combinations with these terpenes as chemical constituents in the correct proportions.
Collapse
Affiliation(s)
| | - Nisha Mathew
- ICMR-Vector Control Research Centre, Puducherry, India
| | | |
Collapse
|
10
|
Rojas EM, Herrera VM, Miranda MC, Rojas DP, Gómez AM, Pallares C, Cobos SM, Pardo L, Gélvez M, Páez A, Mantilla JC, Bonelo A, Parra E, Villar LA. Clinical Indicators of Fatal Dengue in Two Endemic Areas of Colombia: A Hospital-Based Case-Control Study. Am J Trop Med Hyg 2019; 100:411-419. [PMID: 30652671 PMCID: PMC6367622 DOI: 10.4269/ajtmh.17-0323] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Accepted: 08/14/2018] [Indexed: 12/19/2022] Open
Abstract
According to the World Health Organization, 98% of fatal dengue cases can be prevented; however, endemic countries such as Colombia have recorded higher case fatality rates during recent epidemics. We aimed to identify the predictors of mortality that allow risk stratification and timely intervention in patients with dengue. We conducted a hospital-based, case-control (1:2) study in two endemic areas of Colombia (2009-2015). Fatal cases were defined as having either 1) positive serological test (IgM or NS1), 2) positive virological test (RT-PCR or viral isolation), or 3) autopsy findings compatible with death from dengue. Controls (matched by state and year) were hospitalized nonfatal patients and had a positive serological or virological dengue test. Exposure data were extracted from medical records by trained staff. We used conditional logistic regression (adjusting for age, gender, disease's duration, and health-care provider) in the context of multiple imputation to estimate exposure to case-control associations. We evaluated 110 cases and 217 controls (mean age: 35.0 versus 18.9; disease's duration pre-admission: 4.9 versus 5.0 days). In multivariable analysis, retro-ocular pain (odds ratios [OR] = 0.23), nausea (OR = 0.29), and diarrhea (OR = 0.19) were less prevalent among fatal than nonfatal cases, whereas increased age (OR = 2.46 per 10 years), respiratory distress (OR = 16.3), impaired consciousness (OR = 15.9), jaundice (OR = 32.2), and increased heart rate (OR = 2.01 per 10 beats per minute) increased the likelihood of death (AUC: 0.97, 95% confidence interval: 0.96, 0.99). These results provide evidence that features of severe dengue are associated with higher mortality, which strengthens the recommendations related to triaging patients in dengue-endemic areas.
Collapse
Affiliation(s)
- Elsa M. Rojas
- Center for Epidemiological Research, Universidad Industrial de Santander-UIS, Bucaramanga, Colombia
- Info Vida, Bucaramanga, Colombia
| | - Víctor M. Herrera
- Center for Epidemiological Research, Universidad Industrial de Santander-UIS, Bucaramanga, Colombia
| | - María C. Miranda
- Center for Epidemiological Research, Universidad Industrial de Santander-UIS, Bucaramanga, Colombia
| | - Diana Patricia Rojas
- Department of Epidemiology, College of Public Health and Health Professions and College of Medicine, University of Florida, Gainesville, Florida
| | - Adriana M. Gómez
- Center for Epidemiological Research, Universidad Industrial de Santander-UIS, Bucaramanga, Colombia
| | | | | | | | - Margarita Gélvez
- Center for Epidemiological Research, Universidad Industrial de Santander-UIS, Bucaramanga, Colombia
| | - Andrés Páez
- Instituto Nacional de Salud, Bogotá, Colombia
| | - Julio C. Mantilla
- Department of Pathology, Universidad Industrial de Santander-UIS, Bucaramanga, Colombia
| | - Anilza Bonelo
- Emerging Viruses and Disease-VIREM, Universidad del Valle, Cali, Colombia
| | - Edgar Parra
- Instituto Nacional de Salud, Bogotá, Colombia
| | - Luis A. Villar
- Center for Epidemiological Research, Universidad Industrial de Santander-UIS, Bucaramanga, Colombia
| |
Collapse
|
11
|
Ren J, Ling F, Sun J, Gong Z, Liu Y, Shi X, Zhang R, Zhai Y, Chen E, Chen Z. Epidemiological profile of dengue in Zhejiang Province, southeast China. PLoS One 2018; 13:e0208810. [PMID: 30533054 PMCID: PMC6289432 DOI: 10.1371/journal.pone.0208810] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Accepted: 11/23/2018] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Dengue is one of the most important vector-bore infectious diseases in China because of its drastic increase in incidence, geographic extension and profound influence on China's economy. This study aims to retrospectively uncover the epidemiological profile of dengue in Zhejiang, one of the most developed provinces in China, and to find the problem existing in dengue control and prevention. METHODOLOGY Descriptive analyses on the dengue incidence and associated factors were performed. We also identified potential space-time cluster and generated the risk map of dengue. PRINCIPAL FINDINGS A total of 529 cases were reported in Zhejiang Province from 2005 to 2016, and 44.4% were imported. 67.7% of cases were 25~60 years old and the overall male-to-female sex ratio was 1.09:1. Dengue was reported all year round and 70.7% of cases occurred between August and October. Indigenous cases were only reported in the period between July to November and more than half occurred in September. Geographically, dengue was most distributed in Jinghua (3.62 per million), Shaoxing (1.00 per million) and Taizhou (0.81 per million) prefecture level cities. Outbreaks were confirmed in Yiwu, Keqiao and Huangyan counties in 2009, 2015, and 2016, respectively. 73.9% cases would seek medical advice within two days after onset and be confirmed within 9 days after onset. 75.6% would be recognized as dengue within 8 days after their first visit. The time intervals between onset and confirmation (median 7 vs 6 days; Wilcoxon rank sum test Z = -2.40, P = 0.016), first visit and confirmation (median 7 vs 6 days; Wilcoxon rank sum test Z = -2.59, P = 0.009) of indigenous cases were significantly longer than those of imported ones. However, the time intervals between onset and first visit for indigenous cases was shorter (median 0 vs 1 days; Wilcoxon rank sum test Z = -2.10, P = 0.036). Fever (99.1%), fatigue (81.9), rash (63.7%), headache (67.2%) and myalgia (52.60%) were the most frequently mentioned symptoms. CONCLUSIONS Zhejiang has recently witnessed an increase in incidence and geographic extension of dengue. Timely diagnosis is important to stop local transmission and outbreak.
Collapse
Affiliation(s)
- Jiangping Ren
- Zhejiang Provincial Centre for Disease Control and Prevention, Hangzhou, China
- Key Laboratory of Vaccine, Prevention and Control of Infectious Disease of Zhejiang Province, Hangzhou, China
- Field Epidemiology Training Program of Zhejiang Province, Hangzhou, China
| | - Feng Ling
- Zhejiang Provincial Centre for Disease Control and Prevention, Hangzhou, China
- Key Laboratory of Vaccine, Prevention and Control of Infectious Disease of Zhejiang Province, Hangzhou, China
| | - Jimin Sun
- Zhejiang Provincial Centre for Disease Control and Prevention, Hangzhou, China
- Key Laboratory of Vaccine, Prevention and Control of Infectious Disease of Zhejiang Province, Hangzhou, China
| | - Zhenyu Gong
- Zhejiang Provincial Centre for Disease Control and Prevention, Hangzhou, China
- Key Laboratory of Vaccine, Prevention and Control of Infectious Disease of Zhejiang Province, Hangzhou, China
| | - Ying Liu
- Zhejiang Provincial Centre for Disease Control and Prevention, Hangzhou, China
| | - Xuguang Shi
- Zhejiang Provincial Centre for Disease Control and Prevention, Hangzhou, China
| | - Rong Zhang
- Zhejiang Provincial Centre for Disease Control and Prevention, Hangzhou, China
| | - Yujia Zhai
- Zhejiang Provincial Centre for Disease Control and Prevention, Hangzhou, China
| | - Enfu Chen
- Zhejiang Provincial Centre for Disease Control and Prevention, Hangzhou, China
- Key Laboratory of Vaccine, Prevention and Control of Infectious Disease of Zhejiang Province, Hangzhou, China
- * E-mail: (EC); (ZC)
| | - Zhiping Chen
- Zhejiang Provincial Centre for Disease Control and Prevention, Hangzhou, China
- * E-mail: (EC); (ZC)
| |
Collapse
|
12
|
Bibbs CS, Crosier JE, D'Amato JM, Gibson-Corrado J, Xue RD. Bromeliad targeted foliar treatments with Aqualuer ® 20-20 for hot spot mitigation using three hand sprayers against Aedes albopictus (Diptera: Culicidae). JOURNAL OF VECTOR ECOLOGY : JOURNAL OF THE SOCIETY FOR VECTOR ECOLOGY 2018; 43:215-219. [PMID: 30408298 DOI: 10.1111/jvec.12305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Accepted: 05/25/2018] [Indexed: 06/08/2023]
Abstract
Bromeliads serve as a key environmental resource for Aedes albopictus (Skuse) in some peridomestic landscapes and are not addressed through conventional source reduction. As an alternative, three handheld sprayers were evaluated in point-source applications of permethrin to bromeliads in Saint Augustine, FL. Each machine was screened for its utility in point-source harborage treatments, while we simultaneously evaluated bromeliad-focused treatments for reducing Ae. albopictus egg abundance in bromeliad plants. Semi-field tests against caged Ae. albopictus produced 100% mortality at 24 h with each sprayer. Three field sites were assigned to each machine and a control, and bromeliad residual applications of Aqualuer 20-20® were assessed through egg surveillance using ovitraps both within and beyond 30 m of the treated bromeliad harborage. The treatment decreased Ae. albopictus egg abundance across the field sites for three weeks post-treatment with no significant differences among the equipment. Functional differences among machines, such as automated pressure control or leak guards on the nozzle, depend on the accessories that offer the greatest logistical benefit to the user. The field results suggest bromeliads are a viable target for harborage treatments. Selective treatments to bromeliads could offer a possible solution to containers that homeowners refuse to eliminate.
Collapse
Affiliation(s)
- Christopher S Bibbs
- Anastasia Mosquito Control District of St. Johns County, 120 EOC Drive, St. Augustine, FL 32092, U.S.A
| | - Jesse E Crosier
- Anastasia Mosquito Control District of St. Johns County, 120 EOC Drive, St. Augustine, FL 32092, U.S.A
- St. Johns County Department of Health, 200 San Sebastian View, St. Augustine, FL 32084, U.S.A
| | - Joseph M D'Amato
- Anastasia Mosquito Control District of St. Johns County, 120 EOC Drive, St. Augustine, FL 32092, U.S.A
| | - Jennifer Gibson-Corrado
- Anastasia Mosquito Control District of St. Johns County, 120 EOC Drive, St. Augustine, FL 32092, U.S.A
- St. Johns County Department of Health, 200 San Sebastian View, St. Augustine, FL 32084, U.S.A
| | - Rui-De Xue
- Anastasia Mosquito Control District of St. Johns County, 120 EOC Drive, St. Augustine, FL 32092, U.S.A
| |
Collapse
|
13
|
Zongo S, Carabali M, Munoz M, Ridde V. Dengue rapid diagnostic tests: Health professionals' practices and challenges in Burkina Faso. SAGE Open Med 2018; 6:2050312118794589. [PMID: 30147936 PMCID: PMC6100125 DOI: 10.1177/2050312118794589] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Accepted: 07/23/2018] [Indexed: 12/23/2022] Open
Abstract
Objectives Dengue fever remains unrecognized and under-reported in Africa due to several factors, including health professionals' lack of awareness, important prevalence of other febrile illnesses, most of which are treated presumptively as malaria, and the absence of surveillance systems. In Burkina Faso, health centers have no diagnostic tools to identify and manage dengue, which remains ignored, despite the evidence of seasonal outbreaks in recent years. A qualitative study was conducted to analyze the use of rapid diagnostic tests in six health and social promotion centers (i.e. health-care centers, from the French Centers de Santé et de Promotion Sociale) of Ouagadougou (Burkina Faso) in an exploratory research context. Methods Dengue rapid diagnostic tests were introduced into fever-related consultations from December 2013 to January 2014. In-depth individual interviews were conducted in May and June 2014 with 32 health professionals. Results Prior to the introduction of the tests, dengue was not well known or diagnosed by health professionals during consultations. Most febrile cases were routinely presumed to be malaria and treated accordingly. With training and routine use of rapid diagnostic tests, health professionals became more knowledgeable about dengue, improving the diagnosis of non-malaria febrile cases and its management, and better prescription practices. Conclusions In a context of dengue re-emergence and high prevalence of other febrile illnesses, having rapid diagnostic tools available, especially during epidemics reinforces health professionals' diagnostic and prescribing capacities, allowing an opportune and accurate case management and facilitates diseases surveillance.
Collapse
Affiliation(s)
- Sylvie Zongo
- Département Socio-économie et Anthropologie du Développement, Institut des Sciences des Sociétés, Centre National de la Recherche Scientifique et Technologique, Ouagadougou, Burkina Faso
| | - Mabel Carabali
- Department of Epidemiology, Biostatistics and Occupational Health, McGill University Health Centre, Montreal, QC, Canada
| | - Marie Munoz
- Faculté de médicine, Université de Montréal, Montreal, QC, Canada
| | - Valéry Ridde
- IRD (French Institute For Research on sustainable Development), CEPED (IRD-Université Paris Descartes), Universités Paris Sorbonne Cités, ERL INSERM SAGESUD, Paris, France
| |
Collapse
|
14
|
Serum fatty acids and progression from dengue fever to dengue haemorrhagic fever/dengue shock syndrome. Br J Nutr 2018; 120:787-796. [PMID: 30105961 DOI: 10.1017/s0007114518002039] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
PUFA might modulate inflammatory responses involved in the development of severe dengue. We aimed to examine whether serum PUFA concentrations in patients diagnosed with dengue fever (DF) were related to the risk of progression to dengue haemorrhagic fever/dengue shock syndrome (DHF/DSS). A secondary aim was to assess correlations between fatty acids (FA) and inflammatory biomarkers in patients with DF. We conducted a prospective case-control study nested within a cohort of patients who were diagnosed with DF and followed during the acute episode. We compared the distribution of individual FA (% of total FA) at onset of fever between 109 cases who progressed to DHF/DSS and 235 DF non-progressing controls using unconditional logistic regression. We estimated correlations between baseline FA and cytokine concentrations and compared FA concentrations between the acute episode and >1 year post-convalescence in a subgroup. DHA was positively related to progression to DHF/DSS (multivariable adjusted OR (AOR) for DHA in quintile 5 v. 1=5·34, 95 % CI 2·03, 14·1; P trend=0·007). Dihomo-γ-linolenic acid (DGLA) was inversely associated with progression (AOR for quintile 5 v. 1=0·30, 95 % CI 0·13, 0·69; P trend=0·007). Pentadecanoic acid concentrations were inversely related to DHF/DSS. Correlations of PUFA with cytokines at baseline were low. PUFA were lower during the acute episode than in a disease-free period. In conclusion, serum DHA in patients with DF predicts higher odds of progression to DHF/DSS whereas DGLA and pentadecanoic acid predict lower odds.
Collapse
|
15
|
Martins SDT, Kuczera D, Lötvall J, Bordignon J, Alves LR. Characterization of Dendritic Cell-Derived Extracellular Vesicles During Dengue Virus Infection. Front Microbiol 2018; 9:1792. [PMID: 30131785 PMCID: PMC6090163 DOI: 10.3389/fmicb.2018.01792] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2018] [Accepted: 07/17/2018] [Indexed: 12/15/2022] Open
Abstract
The dengue virus (DENV), transmitted by Aedes spp. mosquitoes, is one of the most important arboviral infections in the world. Dengue begins as a febrile condition, and in certain patients, it can evolve severe clinical outcomes, such as dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). The reasons why certain patients develop DHF or DSS have not been thoroughly elucidated to date, and both patient and viral factors have been implicated. Previous work has shown that a severe immune dysfunction involving dendritic cells and T cells plays a key role in increasing the disease severity, especially in secondary heterologous infections. Extracellular vesicles (EVs) are membranous particles that are secreted by several cell types involved in homeostatic and pathological processes. Secretion of EVs by infected cells can enhance immune responses or favor viral evasion. In this study, we compare the molecular content of EVs that are secreted by human primary dendritic cells under different conditions: uninfected or infected with DENV3 strains isolated from patients with different infection phenotypes (a severe case involving DSS and a mild case). Human monocyte-derived dendritic cells (mdDCs) were infected with the dengue virus strains DENV3 5532 (severe) or DENV3 290 (mild), and the EVs were isolated. The presence of cup-shaped EVs was confirmed by electron microscopy and immunostaining with CD9, CD81, and CD83. The RNA content from the mdDC-infected cells contained several mRNAs and miRNAs related to immune responses compared to the EVs from mock-infected mdDCs. A number of these RNAs were detected exclusively during infection with DENV3 290 or DENV3 5532. This result suggests that the differential immune modulation of mdDCs by dengue strains can be achieved through the EV pathway. Additionally, we observed an association of EVs with DENV-infectious particles that seem to be protected from antibodies targeting the DENV envelope protein. We also showed that EVs derived from cells treated with IFN alpha have a protective effect against DENV infection in other cells. These results suggested that during DENV infection, the EV pathway could be exploited to favor viral viability, although immune mechanisms to counteract viral infection can also involve DC-derived EVs.
Collapse
Affiliation(s)
- Sharon de T Martins
- Laboratory of Gene Expression Regulation, Carlos Chagas Institute, FIOCRUZ, Curitiba, Brazil
| | - Diogo Kuczera
- Laboratory of Molecular Virology, Carlos Chagas Institute, FIOCRUZ, Curitiba, Brazil
| | - Jan Lötvall
- Krefting Research Centre, University of Gothenburg, Gothenburg, Sweden
| | - Juliano Bordignon
- Laboratory of Molecular Virology, Carlos Chagas Institute, FIOCRUZ, Curitiba, Brazil
| | - Lysangela R Alves
- Laboratory of Gene Expression Regulation, Carlos Chagas Institute, FIOCRUZ, Curitiba, Brazil
| |
Collapse
|
16
|
|
17
|
Fernandes JN, Moise IK, Maranto GL, Beier JC. Revamping Mosquito-borne Disease Control to Tackle Future Threats. Trends Parasitol 2018; 34:359-368. [PMID: 29500034 DOI: 10.1016/j.pt.2018.01.005] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Revised: 01/19/2018] [Accepted: 01/24/2018] [Indexed: 10/17/2022]
Abstract
The global approach to mosquito-borne diseases (MBDs) is in need of critical re-evaluation. Although there have been dramatic reductions in malaria incidence since 2000, malaria elimination from high-transmission settings remains problematic. At the same time, arbovirus outbreaks have increased in their frequency and impact. The 2015-2016 Zika virus epidemic exposed the dire state of MBD control in many countries, calling for united global action. Despite international resolve to prevent future epidemics, current practices in MBD control are mostly reactive and of limited efficacy. In this Opinion article, we summarize the views of 25 international mosquito experts about the current state of MBD control and highlight the issues that must be addressed in order to tackle emerging threats on the horizon.
Collapse
Affiliation(s)
- Jill N Fernandes
- Global Integrated Disease Surveillance Group, Centre for Animal Science, Queensland Alliance for Agriculture and Food Innovation, University of Queensland, St Lucia, 4072, Australia; Leonard and Jayne Abess Center for Ecosystem Science and Policy, University of Miami, Coral Gables, FL 33146, USA.
| | - Imelda K Moise
- Department of Geography and Regional Studies, University of Miami, Coral Gables, FL 33146, USA; Department of Public Health Sciences, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Gina L Maranto
- Leonard and Jayne Abess Center for Ecosystem Science and Policy, University of Miami, Coral Gables, FL 33146, USA
| | - John C Beier
- Department of Public Health Sciences, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| |
Collapse
|
18
|
Quyen DL, Thanh Le N, Van Anh CT, Nguyen NB, Hoang DV, Montgomery JL, Kutcher SC, Hoang Le N, Hien NT, Hue Kien DT, Rabaa M, O’Neill SL, Simmons CP, Anh DD, Anders KL. Epidemiological, Serological, and Virological Features of Dengue in Nha Trang City, Vietnam. Am J Trop Med Hyg 2018; 98:402-409. [PMID: 29313471 PMCID: PMC5929208 DOI: 10.4269/ajtmh.17-0630] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Accepted: 10/31/2017] [Indexed: 11/07/2022] Open
Abstract
Vietnam is endemic for dengue. We conducted a series of retrospective and prospective studies to characterize the epidemiology of dengue and population mobility patterns in Nha Trang city, Vietnam, with a view to rational design of trials of community-level interventions. A 10-year time series of dengue case notifications showed pronounced interannual variability, as well as spatial heterogeneity in ward-level dengue incidence (median annual coefficient of variation k = 0.47). Of 451 children aged 1-10 years enrolled in a cross-sectional serosurvey, almost one-third had evidence of a past dengue virus (DENV) infection, with older children more likely to have a multitypic response indicative of past exposure to ≥ 1 serotype. All four DENV serotypes were detected in hospitalized patients during 8 months of sampling in 2015. Mobility data collected from 1,000 children and young adults via prospective travel diaries showed that, although all ages spent approximately half of their daytime hours (5:00 am-9:00 pm) at home, younger age groups (≤ 14 years) spent a significantly greater proportion of their time within 500 m of home than older respondents. Together these findings inform the rational design of future trials of dengue preventive interventions in this setting by identifying 1) children < 7 years as an optimal target group for a flavivirus-naive serological cohort, 2) children and young adults as the predominant patient population for a study with a clinical end point of symptomatic dengue, and 3) substantial spatial and temporal variations in DENV transmission, with a consequent requirement for a trial to be large enough and of long enough duration to overcome this heterogeneity.
Collapse
Affiliation(s)
- Duong Le Quyen
- National Institute of Hygiene and Epidemiology, Hanoi, Vietnam
- Institute for Vector Borne Disease, Monash University, Clayton, Australia
| | - Nguyen Thanh Le
- National Institute of Hygiene and Epidemiology, Hanoi, Vietnam
| | - Cao Thi Van Anh
- National Institute of Hygiene and Epidemiology, Hanoi, Vietnam
| | | | - Dong Van Hoang
- National Institute of Hygiene and Epidemiology, Hanoi, Vietnam
| | | | - Simon C. Kutcher
- Institute for Vector Borne Disease, Monash University, Clayton, Australia
| | - Nguyen Hoang Le
- National Institute of Hygiene and Epidemiology, Hanoi, Vietnam
| | | | - Duong Thi Hue Kien
- Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Hospital for Tropical Diseases, Ho Chi Minh City, Vietnam
| | - Maia Rabaa
- Institute for Vector Borne Disease, Monash University, Clayton, Australia
| | - Scott L. O’Neill
- Institute for Vector Borne Disease, Monash University, Clayton, Australia
| | - Cameron P. Simmons
- Institute for Vector Borne Disease, Monash University, Clayton, Australia
- Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Hospital for Tropical Diseases, Ho Chi Minh City, Vietnam
- Department of Microbiology and Immunology, University of Melbourne, Doherty Institute, Melbourne, Australia
| | - Dang Duc Anh
- National Institute of Hygiene and Epidemiology, Hanoi, Vietnam
| | | |
Collapse
|
19
|
|
20
|
Present and Future of Dengue Fever in Nepal: Mapping Climatic Suitability by Ecological Niche Model. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2018; 15:ijerph15020187. [PMID: 29360797 PMCID: PMC5857046 DOI: 10.3390/ijerph15020187] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Revised: 01/12/2018] [Accepted: 01/17/2018] [Indexed: 12/13/2022]
Abstract
Both the number of cases of dengue fever and the areas of outbreaks within Nepal have increased significantly in recent years. Further expansion and range shift is expected in the future due to global climate change and other associated factors. However, due to limited spatially-explicit research in Nepal, there is poor understanding about the present spatial distribution patterns of dengue risk areas and the potential range shift due to future climate change. In this context, it is crucial to assess and map dengue fever risk areas in Nepal. Here, we used reported dengue cases and a set of bioclimatic variables on the MaxEnt ecological niche modeling approach to model the climatic niche and map present and future (2050s and 2070s) climatically suitable areas under different representative concentration pathways (RCP2.6, RCP6.0 and RCP8.5). Simulation-based estimates suggest that climatically suitable areas for dengue fever are presently distributed throughout the lowland Tarai from east to west and in river valleys at lower elevations. Under the different climate change scenarios, these areas will be slightly shifted towards higher elevation with varied magnitude and spatial patterns. Population exposed to climatically suitable areas of dengue fever in Nepal is anticipated to further increase in both 2050s and 2070s on all the assumed emission scenarios. These findings could be instrumental to plan and execute the strategic interventions for controlling dengue fever in Nepal.
Collapse
|
21
|
Arboleda Alzate JF, Rodenhuis-Zybert IA, Hernández JC, Smit JM, Urcuqui-Inchima S. Human macrophages differentiated in the presence of vitamin D3 restrict dengue virus infection and innate responses by downregulating mannose receptor expression. PLoS Negl Trop Dis 2017; 11:e0005904. [PMID: 29020083 PMCID: PMC5653353 DOI: 10.1371/journal.pntd.0005904] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 10/23/2017] [Accepted: 08/23/2017] [Indexed: 02/07/2023] Open
Abstract
Background Severe dengue disease is associated with high viral loads and overproduction of pro-inflammatory cytokines, suggesting impairment in the control of dengue virus (DENV) and the mechanisms that regulate cytokine production. Vitamin D3 has been described as an important modulator of immune responses to several pathogens. Interestingly, increasing evidence has associated vitamin D with decreased DENV infection and early disease recovery, yet the molecular mechanisms whereby vitamin D reduces DENV infection are not well understood. Methods and principal findings Macrophages represent important cell targets for DENV replication and consequently, they are key drivers of dengue disease. In this study we evaluated the effect of vitamin D3 on the differentiation of monocyte-derived macrophages (MDM) and their susceptibility and cytokine response to DENV. Our data demonstrate that MDM differentiated in the presence of vitamin D3 (D3-MDM) restrict DENV infection and moderate the classical inflammatory cytokine response. Mechanistically, vitamin D3-driven differentiation led to reduced surface expression of C-type lectins including the mannose receptor (MR, CD206) that is known to act as primary receptor for DENV attachment on macrophages and to trigger of immune signaling. Consequently, DENV bound less efficiently to vitamin D3-differentiated macrophages, leading to lower infection. Interestingly, IL-4 enhanced infection was reduced in D3-MDM by restriction of MR expression. Moreover, we detected moderate secretion of TNF-α, IL-1β, and IL-10 in D3-MDM, likely due to less MR engagement during DENV infection. Conclusions/Significance Our findings reveal a molecular mechanism by which vitamin D counteracts DENV infection and progression of severe disease, and indicates its potential relevance as a preventive or therapeutic candidate. Dengue represents a major worldwide concern for public health. Clinical complications rely on vascular leak of fluids and molecules from the bloodstream that leads to a potentially fatal hemodynamic compromise. Disease progression has been related to poor control of dengue virus (DENV) dissemination and excessive production of pro-inflammatory mediators that affect the endothelial function. Vitamin D has been shown to modulate immune responses and to alleviate dengue disease. Here, we studied how addition of vitamin D during macrophage differentiation modulates the functional features of these cells in the context of DENV infection. We observed that vitamin D reduced susceptibility of these cells to DENV infection and down-regulated the virus-induced cytokine response. This phenotype was attributed to downregulation of MR, a molecule hijacked by the virus to gain entry into the cells and a key receptor of the MR/CLEC5A complex that links binding and immune activation during DENV infection. Our study sheds light on the mechanism by which vitamin D can restrict DENV dissemination and the cytokine response in macrophages, indicating the potential relevance of this hormone as a preventive and therapeutic candidate.
Collapse
Affiliation(s)
- John F. Arboleda Alzate
- Grupo Inmunovirología, Facultad de Medicina, Universidad de Antioquia UdeA, Medellín, Colombia
- Department of Medical Microbiology, University of Groningen and University Medical Center Groningen, Groningen, The Netherlands
| | - Izabela A. Rodenhuis-Zybert
- Department of Medical Microbiology, University of Groningen and University Medical Center Groningen, Groningen, The Netherlands
| | - Juan C. Hernández
- Infettare, Facultad de Medicina, Universidad Cooperativa de Colombia, Medellín, Colombia
| | - Jolanda M. Smit
- Department of Medical Microbiology, University of Groningen and University Medical Center Groningen, Groningen, The Netherlands
| | - Silvio Urcuqui-Inchima
- Grupo Inmunovirología, Facultad de Medicina, Universidad de Antioquia UdeA, Medellín, Colombia
- * E-mail:
| |
Collapse
|
22
|
The dengue preface to endemic in mainland China: the historical largest outbreak by Aedes albopictus in Guangzhou, 2014. Infect Dis Poverty 2017; 6:148. [PMID: 28934991 PMCID: PMC5609019 DOI: 10.1186/s40249-017-0352-9] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Accepted: 08/17/2017] [Indexed: 01/24/2023] Open
Abstract
Background Dengue was regarded as a mild epidemic in mainland China transmitted by Aedes albopictus. However, the 2014 record-breaking outbreak in Guangzhou could change the situation. In order to provide an early warning of epidemic trends and provide evidence for prevention and control strategies, we seek to characterize the 2014 outbreak through application of detailed cases and entomological data, as well as phylogenetic analysis of viral envelope (E) gene. Methods We used case survey data identified through the Notifiable Infectious Disease Report System, entomological surveillance and population serosurvey, along with laboratory testing for IgM/IgG, NS1, and isolation of viral samples followed by E gene sequencing and phylogenetic analysis to examine the epidemiological and molecular characteristics of the outbreak. Results The 2014 dengue outbreak in Guangzhou accounted for nearly 80% of total reported cases that year in mainland China; a total of 37,376 cases including 37,340 indigenous cases with incidence rate 2908.3 per million and 36 imported cases were reported in Guangzhou, with 14,055 hospitalized and 5 deaths. The epidemic lasted for 193 days from June 11 to December 21, with the highest incidence observed in domestic workers, the unemployed and retirees. The inapparent infection rate was 18.00% (135/750). In total, 96 dengue virus 1 (DENV-1) and 11 dengue virus 2 (DENV-2) strains were isolated. Phylogenetic analysis indicated that the DENV-1 strains were divided into genotype I and V, similar to the strains isolated in Guangzhou and Dongguan in 2013. The DENV-2 strains isolated were similar to those imported from Thailand on May 11 in 2014 and that imported from Indonesia in 2012. Conclusions The 2014 dengue epidemic was confirmed to be the first co-circulation of DENV-1 and DENV-2 in Guangzhou. The DENV-1 strain was endemic, while the DENV-2 strain was imported, being efficiently transmitted by the Aedes albopictus vector species at levels as high as Aedes aegypti. Electronic supplementary material The online version of this article (doi:10.1186/s40249-017-0352-9) contains supplementary material, which is available to authorized users.
Collapse
|
23
|
Vitamin D serostatus and dengue fever progression to dengue hemorrhagic fever/dengue shock syndrome. Epidemiol Infect 2017; 145:2961-2970. [DOI: 10.1017/s0950268817002059] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
SUMMARYVitamin D could modulate pathways leading to dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS). We examined the associations of serum total 25-hydroxy vitamin D [25(OH)D] and vitamin D binding protein (VDBP) concentrations in patients with uncomplicated dengue fever (DF) with risk of progression to DHF/DSS. In a case–control study nested in a cohort of DF patients who were followed during the acute episode in Bucaramanga, Colombia, we compared 25(OH)D and VDBP at onset of fever between 110 cases who progressed to DHF/DSS and 235 DF controls who did not progress. 25(OH)D concentrations were also compared between the acute sample and a sample collected >1 year post-convalescence in a subgroup. Compared with 25(OH)D ⩾75 nmol/l, adjusted odds ratios (95% CI) for progression were 0·44 (0·22–0·88) and 0·13 (0·02–1·05) for 50 to 75 nmol/l (vitamin D insufficiency) and <50 nmol/l (vitamin D deficiency), respectively (P, trend = 0·003). Mean 25(OH)D concentrations were much lower post-convalescence compared with the acute episode, regardless of case status. Compared with controls, mean VDBP was non-significantly lower in cases. We conclude that low serum 25(OH)D concentrations in DF patients predict decreased odds of progression to DHF/DSS.
Collapse
|
24
|
Wilson ME. Emerging infections. Infect Dis (Lond) 2017. [DOI: 10.1002/9781119085751.ch29] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Mary E. Wilson
- Department of Global Health and Population, Harvard T.H. Chan School of Public Health; Harvard University; Boston Massachusetts USA
- School of Medicine; University of California; San Francisco California USA
| |
Collapse
|
25
|
Ernst KC, Walker KR, Reyes-Castro P, Joy TK, Castro-Luque AL, Diaz-Caravantes RE, Gameros M, Haenchen S, Hayden MH, Monaghan A, Jeffrey-Guttierez E, Carrière Y, Riehle MR. Aedes aegypti (Diptera: Culicidae) Longevity and Differential Emergence of Dengue Fever in Two Cities in Sonora, Mexico. JOURNAL OF MEDICAL ENTOMOLOGY 2017; 54:204-211. [PMID: 28082648 PMCID: PMC5853638 DOI: 10.1093/jme/tjw141] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Accepted: 08/08/2016] [Indexed: 05/21/2023]
Abstract
Dengue virus, primarily transmitted by the Aedes aegypti (L.) mosquito, has rapidly expanded in geographic extent over the past several decades. In some areas, however, dengue fever has not emerged despite established Ae. aegypti populations. The reasons for this are unclear and have sometimes been attributed to socio-economic differences. In 2013 we compared Ae. aegypti adult density and population age structure between two cities in Sonora, Mexico: Hermosillo, which has regular seasonal dengue virus transmission, and Nogales, which has minimal transmission. Larval and pupal abundance was greater in Nogales, and adult density was only higher in Hermosillo during September. Population age structure, however, was consistently older in Hermosillo. This difference in longevity may have been one factor that limited dengue virus transmission in Nogales in 2013, as a smaller proportion of Ae. aegypti females survived past the extrinsic incubation period.
Collapse
Affiliation(s)
- Kacey C Ernst
- University of Arizona, Tucson, Arizona (; ; ; ; ; ; ; )
| | | | | | - Teresa K Joy
- University of Arizona, Tucson, Arizona (; ; ; ; ; ; ; )
| | | | | | | | | | - Mary H Hayden
- National Center for Atmospheric Research, Boulder, CO (; )
| | | | | | - Yves Carrière
- University of Arizona, Tucson, Arizona (; ; ; ; ; ; ; )
| | | |
Collapse
|
26
|
[Autochthonous dengue]. Arch Pediatr 2016; 23:1284-1290. [PMID: 27789173 DOI: 10.1016/j.arcped.2016.09.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Revised: 09/15/2016] [Accepted: 09/16/2016] [Indexed: 11/22/2022]
Abstract
Dengue is the arboviral disease that has massively spread in intertropical regions these past few years. The rise in imported cases of dengue and the rapid spread of the Aedes vector mosquitoes in continental France since 2004 explain the occurrence of indigenous dengue cases among the nonimmune population and points to an epidemic risk. Severe dengue cases are rare, but lethality is highest among children under 5 years of age. Like pediatricians in tropical regions, we must learn how dengue presents in metropolitan France and how it can be managed, and pay special attention to severe and potentially fatal forms. The epidemiological, pathophysiological, clinical, diagnostic, and therapeutic characteristics of dengue are presented herein.
Collapse
|
27
|
Bibbs CS, Anderson C, Xue RD. Autodissemination of Insect Growth Regulator, Methoprene, with Two Formulations Against Aedes albopictus. JOURNAL OF THE AMERICAN MOSQUITO CONTROL ASSOCIATION 2016; 32:247-250. [PMID: 27802397 DOI: 10.2987/15-6532.1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Recent autodissemination studies have popularly favored pyriproxyfen, but methoprene is already established and widely used in control programs. This study demonstrated that methoprene could also autodisseminate through contaminated gravid females. Arenas of oviposition cups were arranged around methoprene-contaminated bait stations. Gravid female Aedes albopictus were released to allow oviposition. All cups were then removed and tested in an insect growth regulator bioassay. Liquid formulations did not result in adequate autodissemination among treatment groups. Granular formulations pulverized into a fine powder resulted in successful autodissemination. Emergence inhibition was recorded as high as 85% in individual assays. Pooled inhibition across the granular trials was 56.7%. Methoprene has benefits similar to pyriproxyfen use and has the added advantage of already being established and readily available in existing mosquito control programs throughout the USA. Methoprene is a good candidate for continued investigation of autodissemination.
Collapse
Affiliation(s)
| | - Codi Anderson
- Anastasia Mosquito Control District, 120 EOC Drive, St. Augustine, FL 32092
| | - Rui-De Xue
- Anastasia Mosquito Control District, 120 EOC Drive, St. Augustine, FL 32092
| |
Collapse
|
28
|
Acharya BK, Cao C, Lakes T, Chen W, Naeem S. Spatiotemporal analysis of dengue fever in Nepal from 2010 to 2014. BMC Public Health 2016; 16:849. [PMID: 27549095 PMCID: PMC4994390 DOI: 10.1186/s12889-016-3432-z] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2015] [Accepted: 08/03/2016] [Indexed: 11/10/2022] Open
Abstract
Background Due to recent emergence, dengue is becoming one of the major public health problems in Nepal. The numbers of reported dengue cases in general and the area with reported dengue cases are both continuously increasing in recent years. However, spatiotemporal patterns and clusters of dengue have not been investigated yet. This study aims to fill this gap by analyzing spatiotemporal patterns based on monthly surveillance data aggregated at district. Methods Dengue cases from 2010 to 2014 at district level were collected from the Nepal government’s health and mapping agencies respectively. GeoDa software was used to map crude incidence, excess hazard and spatially smoothed incidence. Cluster analysis was performed in SaTScan software to explore spatiotemporal clusters of dengue during the above-mentioned time period. Results Spatiotemporal distribution of dengue fever in Nepal from 2010 to 2014 was mapped at district level in terms of crude incidence, excess risk and spatially smoothed incidence. Results show that the distribution of dengue fever was not random but clustered in space and time. Chitwan district was identified as the most likely cluster and Jhapa district was the first secondary cluster in both spatial and spatiotemporal scan. July to September of 2010 was identified as a significant temporal cluster. Conclusion This study assessed and mapped for the first time the spatiotemporal pattern of dengue fever in Nepal. Two districts namely Chitwan and Jhapa were found highly affected by dengue fever. The current study also demonstrated the importance of geospatial approach in epidemiological research. The initial result on dengue patterns and risk of this study may assist institutions and policy makers to develop better preventive strategies.
Collapse
Affiliation(s)
- Bipin Kumar Acharya
- University of Chinese Academy of Sciences, No.19A Yuquan Road, Beijing, 100049, China.,Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, No.9 Dengzhuang South Road, Haidian District, Beijing, 100094, China
| | - ChunXiang Cao
- Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, No.9 Dengzhuang South Road, Haidian District, Beijing, 100094, China.
| | - Tobia Lakes
- Department of Geography, Humboldt-Universität zu Berlin, Unter den, Linden, 6, 10099, Berlin, Germany
| | - Wei Chen
- Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, No.9 Dengzhuang South Road, Haidian District, Beijing, 100094, China
| | - Shahid Naeem
- University of Chinese Academy of Sciences, No.19A Yuquan Road, Beijing, 100049, China.,Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, No.9 Dengzhuang South Road, Haidian District, Beijing, 100094, China
| |
Collapse
|
29
|
Andries AC, Duong V, Ong S, Ros S, Sakuntabhai A, Horwood P, Dussart P, Buchy P. Evaluation of the performances of six commercial kits designed for dengue NS1 and anti-dengue IgM, IgG and IgA detection in urine and saliva clinical specimens. BMC Infect Dis 2016; 16:201. [PMID: 27184801 PMCID: PMC4867535 DOI: 10.1186/s12879-016-1551-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Accepted: 05/09/2016] [Indexed: 12/29/2022] Open
Abstract
Background Rapid diagnostic tests (RDTs) have been commercialized in order to help physicians in dengue diagnosis. Until recently, only blood samples were used for those tests but it has been shown in several studies that urine and saliva can also be employed for dengue diagnosis. RDTs for the detection of NS1 antigen and anti-dengue IgG, IgM and IgA in urine and saliva specimens have thus been developed by Standard Diagnostics. The aim of this study was to evaluate the performances these new commercial assays. Methods Two panels of clinical specimens were used: one for the evaluation of the NS1-detection devices and the second for the evaluation of the antibody-detection kits. Each panel consisted of urine and saliva specimens collected sequentially from 86 patients with a confirmed dengue infection. A total of 291 saliva and 440 urine samples were included in the NS1-evaluation panel and 530 saliva and 528 urine specimens constituted the antibody-evaluation panel. All samples were tested in parallel by in-house ELISAs and by the commercial RDTs. Results The RDTs demonstrated an overall sensitivity of 15.5 %/27.9 %/10.7 % for NS1/IgG/IgA detection in urine samples and 20.4 %/ 34.8 %/11 %/6.2 % for NS1/IgG/IgM/IgA detection in saliva samples. Compared to the in-house NS1 ELISA, the results obtained with the NS1 RDT demonstrated a good correlation with urine samples (kappa coefficient: 0.88) but not with saliva specimens (kappa coefficient: 0.28). RDTs designed for antibody detection in saliva and urine were extremely specific (100 %), but less sensitive than the in-house ELISAs (i.e., reduction of the overall sensitivity by 12.2 % for the RDT designed for IgG detection in urine and by 23.7 % for the RDT detecting anti-DENV IgM in saliva). IgM were not detected in urine, either by RDT or ELISA. Conclusions Although the RDTs evaluated here offer an apparently attractive approach for dengue diagnosis, this study suggests that these new commercial kits would require further improvement to increase the sensitivity. Electronic supplementary material The online version of this article (doi:10.1186/s12879-016-1551-x) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Anne-Claire Andries
- Institut Pasteur in Cambodia, International Network of Pasteur Institutes, Virology Unit, Phnom Penh, Cambodia
| | - Veasna Duong
- Institut Pasteur in Cambodia, International Network of Pasteur Institutes, Virology Unit, Phnom Penh, Cambodia
| | - Sivuth Ong
- Institut Pasteur in Cambodia, International Network of Pasteur Institutes, Virology Unit, Phnom Penh, Cambodia
| | - Sopheaktra Ros
- Institut Pasteur in Cambodia, International Network of Pasteur Institutes, Virology Unit, Phnom Penh, Cambodia
| | - Anavaj Sakuntabhai
- Institut Pasteur, Functional Genetics of Infectious Diseases Unit, Paris, France.,Centre National de la Recherche Scientifique, Unité de Recherche Associée 3012, Paris, France
| | - Paul Horwood
- Institut Pasteur in Cambodia, International Network of Pasteur Institutes, Virology Unit, Phnom Penh, Cambodia
| | - Philippe Dussart
- Institut Pasteur in Cambodia, International Network of Pasteur Institutes, Virology Unit, Phnom Penh, Cambodia
| | - Philippe Buchy
- Institut Pasteur in Cambodia, International Network of Pasteur Institutes, Virology Unit, Phnom Penh, Cambodia. .,GlaxoSmithKline, Vaccines R&D, Singapore, Singapore.
| |
Collapse
|
30
|
Vitamin D-Regulated MicroRNAs: Are They Protective Factors against Dengue Virus Infection? Adv Virol 2016; 2016:1016840. [PMID: 27293435 PMCID: PMC4879221 DOI: 10.1155/2016/1016840] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Revised: 04/07/2016] [Accepted: 04/20/2016] [Indexed: 12/19/2022] Open
Abstract
Over the last few years, an increasing body of evidence has highlighted the critical participation of vitamin D in the regulation of proinflammatory responses and protection against many infectious pathogens, including viruses. The activity of vitamin D is associated with microRNAs, which are fine tuners of immune activation pathways and provide novel mechanisms to avoid the damage that arises from excessive inflammatory responses. Severe symptoms of an ongoing dengue virus infection and disease are strongly related to highly altered production of proinflammatory mediators, suggesting impairment in homeostatic mechanisms that control the host's immune response. Here, we discuss the possible implications of emerging studies anticipating the biological effects of vitamin D and microRNAs during the inflammatory response, and we attempt to extrapolate these findings to dengue virus infection and to their potential use for disease management strategies.
Collapse
|
31
|
Bibbs CS, Xue RD. OFF! Clip-on Repellent Device With Metofluthrin Tested on Aedes aegypti (Diptera: Culicidae) for Mortality at Different Time Intervals and Distances. JOURNAL OF MEDICAL ENTOMOLOGY 2016; 53:480-483. [PMID: 26668103 DOI: 10.1093/jme/tjv200] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The OFF! Clip-on mosquito-repellent device was tested outdoors against Aedes aegypti (L.). A single treatment device was used against batches of caged adult, nonblood fed Ae. aegypti at multiple locations 0.3m from treatment center. Another set of cages was stationed 0.6m from treatment. A final set of cages was placed 0.9m away. Trials ran for durations of 5, 15, 30, and 60 min. Initial knockdown and mortality after 24 h was recorded. The devices had effective knockdown and mortality. This was not sustained at distances greater than 0.3m from the device.
Collapse
|
32
|
Klema VJ, Ye M, Hindupur A, Teramoto T, Gottipati K, Padmanabhan R, Choi KH. Dengue Virus Nonstructural Protein 5 (NS5) Assembles into a Dimer with a Unique Methyltransferase and Polymerase Interface. PLoS Pathog 2016; 12:e1005451. [PMID: 26895240 PMCID: PMC4760774 DOI: 10.1371/journal.ppat.1005451] [Citation(s) in RCA: 77] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Accepted: 01/22/2016] [Indexed: 01/07/2023] Open
Abstract
Flavivirus nonstructural protein 5 (NS5) consists of methyltransferase (MTase) and RNA-dependent RNA polymerase (RdRp) domains, which catalyze 5'-RNA capping/methylation and RNA synthesis, respectively, during viral genome replication. Although the crystal structure of flavivirus NS5 is known, no data about the quaternary organization of the functional enzyme are available. We report the crystal structure of dengue virus full-length NS5, where eight molecules of NS5 are arranged as four independent dimers in the crystallographic asymmetric unit. The relative orientation of each monomer within the dimer, as well as the orientations of the MTase and RdRp domains within each monomer, is conserved, suggesting that these structural arrangements represent the biologically relevant conformation and assembly of this multi-functional enzyme. Essential interactions between MTase and RdRp domains are maintained in the NS5 dimer via inter-molecular interactions, providing evidence that flavivirus NS5 can adopt multiple conformations while preserving necessary interactions between the MTase and RdRp domains. Furthermore, many NS5 residues that reduce viral replication are located at either the inter-domain interface within a monomer or at the inter-molecular interface within the dimer. Hence the X-ray structure of NS5 presented here suggests that MTase and RdRp activities could be coordinated as a dimer during viral genome replication.
Collapse
Affiliation(s)
- Valerie J. Klema
- Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch at Galveston, Galveston, Texas, United States of America
| | - Mengyi Ye
- Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch at Galveston, Galveston, Texas, United States of America
| | - Aditya Hindupur
- Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch at Galveston, Galveston, Texas, United States of America
| | - Tadahisa Teramoto
- Department of Microbiology and Immunology, Georgetown University School of Medicine, Washington, D.C., United States of America
| | - Keerthi Gottipati
- Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch at Galveston, Galveston, Texas, United States of America
| | - Radhakrishnan Padmanabhan
- Department of Microbiology and Immunology, Georgetown University School of Medicine, Washington, D.C., United States of America
| | - Kyung H. Choi
- Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch at Galveston, Galveston, Texas, United States of America
- * E-mail:
| |
Collapse
|
33
|
Ismail NA, Dom NC, Ismail R, Ahmad AH, Zaki A, Camalxaman SN. Mitochondrial Cytochrome Oxidase I Gene Sequence Analysis of Aedes Albopictus in Malaysia. JOURNAL OF THE AMERICAN MOSQUITO CONTROL ASSOCIATION 2015; 31:305-312. [PMID: 26675451 DOI: 10.2987/moco-31-04-305-312.1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
A study was conducted to establish polymorphic variation of the mitochondrial DNA encoding the cytochrome oxidase subunit 1 (CO1) gene in Aedes albopictus isolated from 2 hot spot dengue-infested areas in the Subang Jaya District, Malaysia. A phylogenetic analysis was performed with the use of sequences obtained from USJ6 and Taman Subang Mas (TSM). Comparison of the local CO1 sequences with a laboratory strain (USM), alongside reference strains derived from the GenBank database revealed low genetic variation in terms of nucleotide differences and haplotype diversity. Four methods were used to construct a phylogenetic tree and illustrate the genetic relationship of the 37 Ae. albopictus populations based on the CO1 sequences, namely neighbor-joining (NJ), maximum parsimony (MP), maximum likelihood (ML), and Bayesian method, which revealed a distinct relationship between isolates from USJ6 and TSM. Our findings provide new information regarding the genetic diversity among morphologically similar Ae. albopictus, which has not been reported to date.
Collapse
Affiliation(s)
- Nurul-Ain Ismail
- 1 Faculty of Health Sciences, Universiti Teknologi MARA, 42300 Puncak Alam, Selangor, Malaysia
| | - Nazri Che Dom
- 1 Faculty of Health Sciences, Universiti Teknologi MARA, 42300 Puncak Alam, Selangor, Malaysia
| | - Rodziah Ismail
- 1 Faculty of Health Sciences, Universiti Teknologi MARA, 42300 Puncak Alam, Selangor, Malaysia
| | - Abu Hassan Ahmad
- 2 School of Biological Sciences, Universiti Sains Malaysia, 11800 Pulau Pinang, Malaysia
| | - Afiq Zaki
- 1 Faculty of Health Sciences, Universiti Teknologi MARA, 42300 Puncak Alam, Selangor, Malaysia
| | - Siti Nazrina Camalxaman
- 1 Faculty of Health Sciences, Universiti Teknologi MARA, 42300 Puncak Alam, Selangor, Malaysia
| |
Collapse
|
34
|
Identification of a Pyridoxine-Derived Small-Molecule Inhibitor Targeting Dengue Virus RNA-Dependent RNA Polymerase. Antimicrob Agents Chemother 2015; 60:600-8. [PMID: 26574011 DOI: 10.1128/aac.02203-15] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Accepted: 11/10/2015] [Indexed: 01/14/2023] Open
Abstract
The viral RNA-dependent RNA polymerase (RdRp) activity of the dengue virus (DENV) NS5 protein is an attractive target for drug design. Here, we report the identification of a novel class of inhibitor (i.e., an active-site metal ion chelator) that acts against DENV RdRp activity. DENV RdRp utilizes a two-metal-ion mechanism of catalysis; therefore, we constructed a small library of compounds, through mechanism-based drug design, aimed at chelating divalent metal ions in the catalytic site of DENV RdRp. We now describe a pyridoxine-derived small-molecule inhibitor that targets DENV RdRp and show that 5-benzenesulfonylmethyl-3-hydroxy-4-hydroxymethyl-pyridine-2-carboxylic acid hydroxyamide (termed DMB220) inhibited the RdRp activity of DENV serotypes 1 to 4 at low micromolar 50% inhibitory concentrations (IC50s of 5 to 6.7 μM) in an enzymatic assay. The antiviral activity of DMB220 against DENV infection was also verified in a cell-based assay and showed a 50% effective concentration (EC50) of <3 μM. Enzyme assays proved that DMB220 was competitive with nucleotide incorporation. DMB220 did not inhibit the enzymatic activity of recombinant HIV-1 reverse transcriptase and showed only weak inhibition of HIV-1 integrase strand transfer activity, indicating high specificity for DENV RdRp. S600T substitution in the DENV RdRp, which was previously shown to confer resistance to nucleoside analogue inhibitors (NI), conferred 3-fold hypersusceptibility to DMB220, and enzymatic analyses showed that this hypersusceptibility may arise from the decreased binding/incorporation efficiency of the natural NTP substrate without significantly impacting inhibitor binding. Thus, metal ion chelation at the active site of DENV RdRp represents a viable anti-DENV strategy, and DMB220 is the first of a new class of DENV inhibitor.
Collapse
|