Preventing dengue epidemics: how to better assist holistic vaccination efforts

Abstract Diseases caused by flaviviruses are a major public health burden across the world. In the past decades, South America has suffered dengue epidemics, the re-emergence of yellow fever and St. Louis encephalitis viruses, and the introduction of West Nile and Zika viruses. Many insect-specific flaviviruses (ISFs) that cannot replicate in vertebrate cells have recently been described. In this study, we analyzed field-collected mosquito samples from six different ecoregions of Argentina to detect flaviviruses. We did not find any RNA belonging to pathogenic flaviviruses or ISFs in adults or immature stages. However, flaviviral-like DNA similar to flavivirus NS5 region was detected in 83–100% of Aedes aegypti (L.). Despite being previously described as an ancient element in the Ae. aegypti genome, the flaviviral-like DNA sequence was not detected in all Ae. aegypti samples and sequences obtained did not form a monophyletic group, possibly reflecting the genetic diversity of mosquito populations in Argentina.

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Molecular epidemiology of dengue viruses in Brazil

Cadernos de Saúde Pública ◽

10.1590/s0102-311x2000000100021 ◽

2000 ◽

Vol 16 (1) ◽

pp. 205-211 ◽

Cited By ~ 7

Author(s):

Rita Maria Ribeiro Nogueira ◽

Marize Pereira Miagostovich ◽

Hermann Gonçalves Schatzmayr

Keyword(s):

Genetic Variability ◽

Molecular Epidemiology ◽

Epidemiological Studies ◽

Dengue Viruses ◽

Laboratory Evidence ◽

Dengue Epidemics

Dengue viruses (DEN) are found as four antigenically distinct serotypes designated DEN-1, 2, 3, and 4. Laboratory evidence that strain-intratypical variation occurs among DEN viruses has been demonstrated since the 1970s, although only with the advances in molecular technologies has it been possible to determine the genetic variability of each serotype. Genotypical identification has proven to be a useful tool for determining the origin and spread of epidemics and to correlate virulence of strains. In this report we present the results of molecular epidemiological studies with the DEN-1 and DEN-2 viruses that caused dengue epidemics in Brazil during the last decade.

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Impact of spatially heterogeneous temperature on the dynamics of dengue epidemics

Discrete & Continuous Dynamical Systems - B ◽

10.3934/dcdsb.2018099 ◽

2019 ◽

Vol 24 (1) ◽

pp. 321-349 ◽

Cited By ~ 2

Author(s):

Naveen K. Vaidya ◽

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Xianping Li ◽

Feng-Bin Wang ◽

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...

Keyword(s):

Dengue Epidemics

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Seasonal patterns of dengue incidence in Thailand across the urban-rural gradient

10.1101/2020.11.25.20186056 ◽

2020 ◽

Author(s):

Qifang Bi ◽

Derek AT Cummings ◽

Nicholas G. Reich ◽

Lindsay T. Keegan ◽

Joshua Kaminsky ◽

...

Keyword(s):

Wavelet Analysis ◽

Temporal Variation ◽

Rural Areas ◽

Urban Areas ◽

Dynamic Models ◽

Seasonal Patterns ◽

Disease Dynamics ◽

Urban Rural ◽

Spatio Temporal ◽

Dengue Epidemics

AbstractIn Southeast Asia, endemic dengue follows strong spatio-temporal patterns with major epidemics occurring every 2-5 years. However, important spatio-temporal variation in seasonal dengue epidemics remains poorly understood. Using 13 years (2003-2015) of dengue surveillance data from 926 districts in Thailand and wavelet analysis, we show that rural epidemics lead urban epidemics within a dengue season, both nationally and within health regions. However, local dengue fade-outs are more likely in rural areas than in urban areas during the off season, suggesting rural areas are not the source of viral dispersion. Simple dynamic models show that stronger seasonal forcing in rural areas could explain the inconsistency between earlier rural epidemics and dengue “over wintering” in urban areas. These results add important nuance to earlier work showing the importance of urban areas in driving multi-annual patterns of dengue incidence in Thailand. Feedback between geographically linked locations with markedly different ecology is key to explaining full disease dynamics across urban-rural gradient.

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