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Arbovirus Infections As Screening Tools for the Identification of Viral Immunomodulators and Host Antiviral Factors
Published on: September 13, 2018
Host range, amplification and arboviral disease emergence
1Center for Biodefense and Emerging Infectious Diseases and Department of Pathology, University of Texas Medical Branch, Galveston, Texas 77555-0609, USA. sweaver@utmb.edu
Archives of Virology. Supplementum
|December 20, 2005
Summary
Arboviruses like dengue viruses (DENV) can adapt to humans as amplification hosts, leading to urban outbreaks. Understanding these evolutionary shifts is key for disease control and potential eradication.
Area of Science:
- Arbovirology
- Evolutionary Biology
- Epidemiology
Background:
- Arboviruses are zoonotic pathogens transmitted by arthropods, with human exposure occurring via spillover from enzootic cycles.
- Some arboviruses amplify in livestock, increasing human exposure in rural areas.
- Yellow fever and dengue viruses (DENV) have adapted to humans as amplification hosts, driving urban transmission.
Purpose of the Study:
- To explore the evolutionary adaptations of arboviruses, particularly DENV, to human hosts.
- To understand the transition from sylvatic transmission cycles to urban epidemics.
- To inform strategies for arboviral disease control and potential eradication.
Main Methods:
- Comparative analysis of sylvatic and urban forms of DENV.
- Review of arboviral transmission cycles and host-pathogen interactions.
- Examination of vector competence and host adaptation.
Main Results:
- DENV evolved from sylvatic cycles in nonhuman primates to efficient transmission by urban mosquitoes like Aedes aegypti and Ae. albopictus.
- Human amplification hosts facilitate urban spread of arboviruses.
- Adaptive mutations enable efficient viremia in secondary hosts like equines for VEEV.
Conclusions:
- The adaptation of arboviruses to humans represents a significant evolutionary step, enabling urban epidemics.
- Comparative studies of DENV forms can reveal insights into arboviral virulence evolution.
- Understanding these adaptations is crucial for developing effective vaccines and eradication strategies for arboviral diseases.
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