scholarly journals Administration of defective virus inhibits dengue transmission into mosquitoes

2019 ◽  
Author(s):  
Tarunendu Mapder ◽  
John Aaskov ◽  
Kevin Burrage
Keyword(s):  
Dengue Virus ◽  
Virus Transmission ◽  
Dengue Transmission ◽  
Dengue Outbreaks ◽  
Mosquito Pool ◽  
Bang Bang Control ◽  
Defective Virus ◽  
Successful Reduction ◽  
Transmission Models ◽  
Improve Disease Control

The host-vector shuttle and the bottleneck in dengue transmission is a significant aspect with regard to the study of dengue outbreaks. As mosquitoes require 100-1000 times more virus to become infected than human, the transmission of dengue virus from human to mosquito is a vulnerability that can be targeted to improve disease control. In order to capture the heterogeneity in the infectiousness of an infected patient population towards the mosquito pool, we calibrate a population of host-to-vector virus transmission models based on an experimentally quantified infected fraction of a mosquito population. Once the population of models is well-calibrated, we deploy a population of controls that helps to inhibit the human-to-mosquito transmission of the dengue virus indirectly by reducing the viral load in the patient body fluid. We use an optimal bang-bang control on the administration of the defective virus (transmissible interfering particles, known as TIPs) to symptomatic patients in the course of their febrile period and observe the dynamics in successful reduction of dengue spread into mosquitoes.

scholarly journals Administration of Defective Virus Inhibits Dengue Transmission into Mosquitoes

Viruses ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 558
Author(s):  
Tarunendu Mapder ◽  
John Aaskov ◽  
Kevin Burrage
Keyword(s):  
Dengue Virus ◽  
Virus Transmission ◽  
Mosquito Population ◽  
Dengue Transmission ◽  
Dengue Outbreaks ◽  
Bang Bang Control ◽  
Defective Virus ◽  
Successful Reduction ◽  
Transmission Models ◽  
Improve Disease Control

The host-vector shuttle and the bottleneck in dengue transmission is a significant aspect with regard to the study of dengue outbreaks. As mosquitoes require 100–1000 times more virus to become infected than human, the transmission of dengue virus from human to mosquito is a vulnerability that can be targeted to improve disease control. In order to capture the heterogeneity in the infectiousness of an infected patient population towards the mosquito population, we calibrate a population of host-to-vector virus transmission models based on an experimentally quantified infected fraction of a mosquito population. Once the population of models is well-calibrated, we deploy a population of controls that helps to inhibit the human-to-mosquito transmission of the dengue virus indirectly by reducing the viral load in the patient body fluid. We use an optimal bang-bang control on the administration of the defective virus (transmissible interfering particles (TIPs)) to symptomatic patients in the course of their febrile period and observe the dynamics in successful reduction of dengue spread into mosquitoes.

Geographical heterogeneity of dengue transmission in two villages in southern Vietnam

2009 ◽  
Vol 138 (4) ◽  
pp. 585-591 ◽  
Author(s):  
K. T. D. THAI ◽  
N. NAGELKERKE ◽  
H. L. PHUONG ◽  
T. T. T. NGA ◽  
P. T. GIAO ◽  
...  
Keyword(s):  
Dengue Virus ◽  
Virus Transmission ◽  
Null Distribution ◽  
Household Level ◽  
Geographical Heterogeneity ◽  
Asymptomatic Children ◽  
Dengue Transmission ◽  
Risk Areas ◽  
Serological Data ◽  
And Control

SUMMARYThis study was performed to test the hypothesis that there are ‘hotspots’, i.e. geographical heterogeneity, of dengue transmission. Data from two repeat serosurveys in two villages in Vietnam were used to identify incident infections and to relate these to prevalence at baseline and thus assess geographical heterogeneity, i.e. clustering, in dengue transmission. A total of 400 households were surveyed; serological data from 521 children at baseline and from 119 children at follow-up were included in a spatial analysis. Geographical heterogeneity of dengue transmission was explored using a permutation null distribution test. This showed for the first time evidence of clustering of dengue virus transmission at the household level in asymptomatic children. Risk areas could be identified by seroprevalence surveys combined with mapping. Control of dengue virus transmission could be supported by identification and control of hotspots.

scholarly journals Entomological Risk Assessment for Dengue Virus Transmission during 2016–2020 in Kamphaeng Phet, Thailand

Pathogens ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 1234
Author(s):  
Thanyalak Fansiri ◽  
Darunee Buddhari ◽  
Nattaphol Pathawong ◽  
Arissara Pongsiri ◽  
Chonticha Klungthong ◽  
...  
Keyword(s):  
Risk Assessment ◽  
Dengue Virus ◽  
Case Reports ◽  
Virus Transmission ◽  
Denv Infection ◽  
Larval Abundance ◽  
Dengue Case ◽  
Vector Surveillance ◽  
Household Level ◽  
Dengue Transmission

Individual houses with high risks of dengue virus (DENV) transmission might be a source of virus transmission within the neighborhood. We conducted an entomological risk assessment for DENV transmission at the household level, comprising family cohort members residing in the same location, to assess the risk for dengue virus transmitted by mosquito vectors. The studies were conducted in Kamphaeng Phet Province, Thailand, during 2016–2020. Entomological investigations were performed in 35 cohort families on day 1 and day 14 after receiving dengue case reports. DENV was found in 22 Aedes samples (4.9%) out of 451 tested samples. A significantly higher DENV infection rate was detected in vectors collected on day 1 (6.64%) compared to those collected on day 14 (1.82%). Annual vector surveillance was carried out in 732 houses, with 1002 traps catching 3653 Aedes females. The majority of the 13,228 water containers examined were made from plastic and clay, with used tires serving as a primary container, with 59.55% larval abundance. Larval indices, as indicators of dengue epidemics and to evaluate disease and vector control approaches, were calculated. As a result, high values of larval indices indicated the considerably high risk of dengue transmission in these communities.

scholarly journals Predicting dengue outbreaks at neighbourhood level using human mobility in urban areas

2020 ◽  
Vol 17 (171) ◽  
pp. 20200691
Author(s):  
Rafael Bomfim ◽  
Sen Pei ◽  
Jeffrey Shaman ◽  
Teresa Yamana ◽  
Hernán A. Makse ◽  
...  
Keyword(s):  
Neural Networks ◽  
Dengue Virus ◽  
Urban Areas ◽  
Human Mobility ◽  
Mechanistic Models ◽  
Mobility Data ◽  
Dengue Transmission ◽  
Neighbourhood Level ◽  
Dengue Outbreaks ◽  
The Impact

Dengue is a vector-borne disease transmitted by the Aedes genus mosquito. It causes financial burdens on public health systems and considerable morbidity and mortality. Tropical regions in the Americas and Asia are the areas most affected by the virus. Fortaleza is a city with approximately 2.6 million inhabitants in northeastern Brazil that, during the recent decades, has been suffering from endemic dengue transmission, interspersed with larger epidemics. The objective of this paper is to study the impact of human mobility in urban areas on the spread of the dengue virus, and to test whether human mobility data can be used to improve predictions of dengue virus transmission at the neighbourhood level. We present two distinct forecasting systems for dengue transmission in Fortaleza: the first using artificial neural network methods and the second developed using a mechanistic model of disease transmission. We then present enhanced versions of the two forecasting systems that incorporate bus transportation data cataloguing movement among 119 neighbourhoods in Fortaleza. Each forecasting system was used to perform retrospective forecasts for historical dengue outbreaks from 2007 to 2015. Results show that both artificial neural networks and mechanistic models can accurately forecast dengue cases, and that the inclusion of human mobility data substantially improves the performance of both forecasting systems. While the mechanistic models perform better in capturing seasons with large-scale outbreaks, the neural networks more accurately forecast outbreak peak timing, peak intensity and annual dengue time series. These results have two practical implications: they support the creation of public policies from the use of the models created here to combat the disease and help to understand the impact of urban mobility on the epidemic in large cities.

scholarly journals PENYEBARAN VIRUS DENGUE SECARA TRANSOVARIAL PADA VEKTOR DEMAM BERDARAH DENGUE NYAMUK Aedes aegypti

2019 ◽  
Vol 12 (4) ◽  
pp. 216-223
Author(s):  
Devita Febriani Putri ◽  
Nurhaida Widiani ◽  
Debi Arivo
Keyword(s):  
Aedes Aegypti ◽  
Dengue Virus ◽  
Prediction Models ◽  
Virus Transmission ◽  
Hemorrhagic Fever ◽  
Transovarial Transmission ◽  
Scientific Article ◽  
Vector Surveillance ◽  
Population Vector ◽  
Dengue Outbreaks

TRANSOVARIAL TRANSMISSION OF DENV IN AEDES AEGYPTI Background: Transovarial transmission of dengue virus in Aedes aegypti mosquitoes is a vertical transmission of dengue virus infection in female Ae. aegypti mosquitoes to the offspring. The phenomenon of transovarial dengue virus transmission in Dengue Hemorrhagic Fever (DHF) vectors has been proven by laboratory and nature, which indicates the transovarial transmission of dengue virus has an important role in maintaining the dengue epidemic. DHF vector control especially Ae. aegypti mosquitoes is an effective method of stopping transmission and expansion of dengue cases.Purpose: This scientific article aims to understand the spread of dengue virus transovarially in dengue mosquito vectors, and its relation to the prediction of outbreak dengue cases as information on DHF vector surveillance so that it can make the appropriate control program.Methods: Collecting several scientific articles to obtain information on the studies that have been done and summarizing the results of the study.Results: Several result of study are proving that transovarial transmission of dengue virus in Aedes spp. mosquitoes  can predict dengue outbreaks case by monitoring the stadium immature Aedes sp., but it need further comprehension statistically about occurrence of dengue outbreaks and the increasing of dengue virus infections in immature stadium of mosquitoes.Discussion: Transovarial transmission rates from Ae. aegypti mosquito sample obtained from nature may be lower than in the laboratory, because laboratory condition can be controlled in accordande with the development of viruses in mosquito bodies. The dengue virus is proven to be able to spread between stages from eggs, larvae, pupae to imago and Ae. aegypti mosquitoes can act as reservoirs for  dengue virus until the 7th progeni.Conclusion: Dispersion dengue virus through transovarial in Ae. aegypti mosquito playing important role in viruses maintained in nature during absence of viremic vertebrata host or when the climate condition are not favorable for that viruses. Continuous monitoring of Ae. aegypti mosquitoes population vector related the early detection of virus circulation may contribute to the prediction models for dengue outbreaks, so that DHF control can be more effective.Pendahuluan: Penularan virus dengue secara transovarial pada nyamuk Aedes aegypti adalah transmisi secara vertikal dari nyamuk Ae. aegypti betina yang infektif virus dengue kepada keturunannya. Fenomena penularan transovarial virus dengue pada vektor Demam Berdarah Dengue (DBD) telah banyak dibuktikan skala laboratorium dan secara natural di alam, yang mengindikasikan penularan transovarial virus dengue memiliki peranan penting dalam mempertahankan epidemik DBD. Pengendalian vektor DBD khususnya nyamuk Ae. aegypti merupakan salah satu metode efektif dalam menghentikan penularan dan perluasan kasus DBD.Tujuan: Studi ini untuk memahami penyebaran virus dengue secara transovarial  pada vektor nyamuk DBD, serta kaitannya  terhadap prediksi kasus luar biasa (KLB) DBD sebagai informasi surveilans vektor DBD sehingga dapat membuat program pengendalian yang tepat.Metode: Dengan mengumpulkan beberapa artikel ilmiah untuk mendapatkan informasi studi yang telah dilakukan sebelumnya dan membuat ringkasan dari hasil studi tersebut.Hasil: Beberapa studi membuktikan penelitian transovarial virus dengue pada nyamuk Aedes spp. dapat memprediksi kasus KLB DBD dengan cara memonitoring stadium immature Aedes sp., namun perlu dilakukan studi statistik lebih lanjut untuk membuktikan hubungan terjadinya KLB DBD dan meningkatnya infeksi virus dengue pada stadium immature nyamuk.Pembahasan: Angka infeksi penularan transovarial virus dengue dari sampel nyamuk Ae. aegypti yang didapatkan langsung dari alam lebih rendah dari skala laboratorium, dikarenakan kondisi laboratorium dapat dikendalikan sesuai dengan perkembangan virus ditubuh nyamuk. Virus dengue terbukti dapat menyebar antar stadium dari telur, larva, pupa, sampai imago dan nyamuk Ae. aegypti dapat menjadi reservoir virus dengue sampai progeni ke 7.Kesimpulan: Penyebaran virus dengue secara transovarial pada nyamuk Ae. aegypti berperan penting dalam mempertahankan keberadaan virus di alam khususnya dimana tidak ada hospes vertebrata yang viremik atau ketika  keadaan (kondisi iklim) yang tidak menguntungkan virus tersebut di alam. Pemantauan berkelanjutan pada vektor demam berdarah nyamuk Ae. aegypti terkait deteksi dini sirkulasi virus dengue dapat berkontribusi pada pengembangan model prediksi KLB DBD, sehingga pengendalian DBD dapat lebih efektif.

scholarly journals Dengue Virus Transmission from Donor to Recipient during Haploidentical Stem Cell Transplantation

IDCases ◽  
2021 ◽  
pp. e01220
Author(s):  
Anjali Yadav ◽  
Neha Rastogi ◽  
K. Upasana ◽  
Sunisha Arora ◽  
Dhwanee Thakkar ◽  
...  
Keyword(s):  
Stem Cell ◽  
Stem Cell Transplantation ◽  
Dengue Virus ◽  
Cell Transplantation ◽  
Virus Transmission ◽  
Haploidentical Stem Cell Transplantation

scholarly journals TRANSMISI TRANSOVARIAL VIRUS DENGUE PADA NYAMUKAEDES SPP.

2013 ◽  
Vol 5 (1) ◽  
Author(s):  
Angle M. H. Sorisi
Keyword(s):  
Dengue Virus ◽  
Vertical Transmission ◽  
Dengue Hemorrhagic Fever ◽  
Virus Transmission ◽  
Hemorrhagic Fever ◽  
Health Problems ◽  
Transovarial Transmission ◽  
Blood Sucking ◽  
Endemic Areas ◽  
And Control

Abstract: Dengue Hemorrhagic Fever (DHF) is one of the most serious health problems in Indonesia which often causes outbreaks with numerous deaths. The disease is transmitted byAedes sp.females. Generally, dengue virus transmission occurs horizontally from human carriers, and the dengue viruses are passed on bytheir vectors through blood sucking activity. After propagation in the mosquito, the viruses are transmitted to human recipients. In addition, there is a vertical transmission (transovarial) of dengue virusesin the ova of Aedes sp.females. The viruses propagate in the ova that undergo  metamorphosis to become larvae, pupae, and imagoes. The transovarial transmission of dengue virusesin its vectors in endemic areas could be a causative key which is responsible for the phenomenon of increasing cases of DHF. Any effort to prevent and control DHF requires a thorough understanding about virDen transmission, including this transovarial transmission in Aedes spfemales. Keywords: DHF, transovarial transmission, Aedes sp.     Abstrak: Penyakit Demam Berdarah Dengue (DBD) merupakan salah satu masalah kesehatan yang semakin serius di Indonesia dan sering menimbulkan suatu Kejadian Luar Biasa (KLB) dengan jumlah kematian tinggi. Penyakit ditularkan melalui Aedes sp.betina. Transmisi virus dengue umumnya terjadi secara horizontal, yaitu dari manusia pembawa virus dengue ke nyamuk vektor Aedes sp. melalui aktivitasnya mengisap darahSetelah mengalami propagasi  dalam  tubuh nyamuk, virus dengue ditularkan ke  manusia penerima. Selain itu, transmisi virus dapat terjadi secara vertikal (transovarial) yaitu virus dengue dalam tubuh nyamuk vektorAedes sp. betinake ovum, kemudian berpropagasi dalam ovum, larva, pupa, dan imago. Transmisi transovarial virus dengueke vektornya di daerah endemik bisa menjadi kunci penyebab yang bertanggung jawab terhadap fenomena peningkatan kasus deman berdarah dengue. Upaya pencegahan dan penanggulangan DBD memerlukan pengetahuan yang matang tentang adanya infeksi transovarial virDen pada nyamuk Aedes sp. Kata kunci : DBD, transmisi transovarial,  Aedes sp.

scholarly journals The influence of natural environmental condition towards the existence of vector's larva of dengue hemorrhagic fever: Aedes Aegypti

2017 ◽  
Author(s):  
Susiana Nugraha
Keyword(s):  
Logistic Regression ◽  
Aedes Aegypti ◽  
Dengue Virus ◽  
Dengue Hemorrhagic Fever ◽  
Water Reservoir ◽  
Hemorrhagic Fever ◽  
Morbidity Rate ◽  
Tropical Regions ◽  
Water Replacement ◽  
Dengue Outbreaks

Dengue hemorrhagic fever is a severe and fatal infection that occurs in tropical regions such as Indonesia. In 2014, recorded that dengue morbidity rate was 5.17 per 100,000 inhabitants (approximately 13031 cases) with mortality rate of 0.84% (110 deaths). Demographic and societal changes such as population growth, urbanization, and modern transportation appear to play an important role in the increased incidence and geographical spread of dengue virus. Aedes aegypti, the urban yellow fever mosquito, is also the principal dengue-carrying vector. The Aedes aegypti mosquitoes as a vector of dengue virus normally live and breed in clean water reservoirs that are not directly related to the land such as: bath, bird drinks, water pot, water jars / barrel, cans, old tires, etc. In Indonesia, dengue outbreaks often occur when the seasons change from dry to rain hor vice versa. This study aimed to figure out the influence of natural environment and the existence of the vector’s larva. A logistic regression was performed to ascertain the effects of temperature, humidity, water replacement and the existence of water reservoir on the likelihood of the existence of the vector’s larva . The logistic regression model was statistically significant, p < .005 and the model explained 69% (Nagelkerke R2). This finding shows that the existence of the mosquito’s larva, influenced by temperature, water replacement activity and the existence of water reservoir. Health education about vector control and environmental engineering are necessary to break the chain of mosquito breeding.

scholarly journals Knowledge About Dengue Fever Prevention Among People Visiting Benazir Bhutto Hospital

2020 ◽  
Vol 24 (1) ◽  
pp. 23-26
Author(s):  
Tamanna Fayyaz ◽  
Maria Yasin ◽  
Ahsan Tariq ◽  
Aashi Mughal ◽  
Mujtaba Haider Bukhari ◽  
...  
Keyword(s):  
Dengue Virus ◽  
Dengue Fever ◽  
Public Awareness ◽  
Virus Transmission ◽  
Cross Sectional Study ◽  
Ethical Review ◽  
Health Campaigns ◽  
Cross Sectional ◽  
High Knowledge ◽  
Public Health Campaigns

Background: The higher incidence of dengue fever in Pakistan demands additional efforts in order to limit the disease. Despite active public health campaigns, low public awareness is one of the factors facilitating dengue virus transmission. For effective preventive measures, the assessment of the knowledge gap and then taking appropriate steps to fill the gap is required.The objective of this study is to assess knowledge about dengue fever prevention among people visiting Benazir Bhutto Hospital, Rawalpindi.Methods: The descriptive cross-sectional study of 6 months duration was conducted with 280 participants selected via nonprobability convenience sampling. After informed consent, an interview was conducted based on a questionnaire that assessed socio-demographic parameters and knowledge about dengue virus transmission and prevention. Data were analyzed through SPSS v. 22. The study was approved by the Ethical Review Board (ERB) of Rawalpindi Medical University and Allied hospitals.Results: Out of 280 respondents, 54.6% were males and 45.4% females and the mean age was 35.0 ± 13.1 years. The respondents having high knowledge scores were 66(23.6%) while those having moderate and low scores were 159 (56.8%) and 55 (19.6%) respectively. Educated respondents (p=0.03) and urban residents (p=0.05) had higher knowledge scores.Conclusion: The majority of the participants know about dengue fever. However, only one out of every four respondents has good knowledge scores for dengue fever prevention.

Sign in / Sign up

Export Citation Format

Share Document