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Vector Competence Analyses on Aedes aegypti Mosquitoes using Zika Virus
Published on: May 31, 2020
West Nile virus in the Americas
Lyle R Petersen1, Edward B Hayes
1Division of Vector-borne Infectious Diseases, National Center for Zoonotic, Vector-borne, and Enteric Diseases, Centers for Disease Control and Prevention, 1350 Rampart Road, Fort Collins, CO 80521, USA. lxp2@cdc.gov
The Medical Clinics of North America
|January 17, 2009
Summary
West Nile virus rapidly spread across the Americas, causing severe human neuroinvasive disease in North America. Surprisingly, Latin America and the Caribbean show low disease impact despite similar virus strains.
Area of Science:
- Veterinary Public Health
- Infectious Disease Epidemiology
- Arbovirology
Background:
- West Nile virus (WNV) emerged in the Western Hemisphere in 1999, rapidly spreading across North and South America.
- North America experiences significant annual epidemics of human neuroinvasive disease, posing a substantial public health burden.
- Non-vector-borne transmission, including via blood transfusion and organ transplantation, has been documented due to high human infection rates.
Purpose of the Study:
- To analyze the epidemiological patterns of West Nile virus across the Americas.
- To investigate the reasons for differential disease impact in North America versus Latin America and the Caribbean.
Main Methods:
- Review of WNV surveillance data across North, Central, and South America, and the Caribbean.
- Comparative analysis of WNV strain genetic data from affected regions.
- Examination of documented human, avian, and equine morbidity and mortality rates.
Main Results:
- WNV has established widespread circulation from Canada to Argentina.
- North America exhibits a high incidence of neuroinvasive disease, with significant public health consequences.
- Latin America and Caribbean regions report unexpectedly low WNV-associated morbidity and mortality, even with genetically similar WNV strains.
Conclusions:
- The epidemiology of West Nile virus varies significantly across the Americas.
- Factors beyond viral strain similarity likely influence the severity of WNV disease in different geographic areas.
- Further research is needed to understand the drivers of low disease burden in Latin America and the Caribbean.
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