LONG NON-CODING RNAS IN VENEZUELAN EQUINE ENCEPHALITIS VIRUS INFECTION
Abstract
VEEV. Alphaviruses belong to the Togaviridae family. They are enveloped, positive sense single-stranded RNA viruses. Old World alphaviruses include chikungunya virus and Sindbis virus, which cause arthralgic disease. New World alphaviruses include Venezuelan equine encephalitis virus (VEEV), which can cause severe encephalitis in humans. VEEV is a Category B pathogen that is transmitted naturally by mosquitoes, but can also become infectious upon aerosolization, making it a concern for bioweaponization. Natural transmission occurs between the mammalian hosts (rodents) via a mosquito vector during the enzootic cycle. Bites from infected mosquitos to non-host species initiate the epizootic cycle, resulting in severe infection in more susceptible species, including horses and humans. VEEV infection in humans often results in a self-resolving mild flu-like syndrome. In a subset of patients, severe disease can occur, beginning with flu-like symptoms and progressing to encephalitis with high mortality. Overall, 1-4% of VEEV patients develop neurological symptoms, which can cause lethality or lifelong damage; additionally, birth defects and fetal demise can occur in infected pregnant women. In the first stage of infection via the subcutaneous route, VEEV infects cells of the immune system, namely dendritic cells in draining lymph nodes 1,2. After 2-3 days, the virus is cleared from the periphery but moves to the brain, where it replicates in neurons and astrocytes and causes encephalitis. In aerosol infection, the virus infects cells in the lung before traveling to neural tissues. There is an experimental VEEV vaccine (TC-83) given to select personnel, but its efficacy is unknown, and it has a substantial side effects 3. Although an inactivated vaccine exists, it is given to equids but not typically administered to humans. Therefore, VEEV is dangerous due to its ability to cause severe disease with significant mortality and long-term morbidity, its history of bioweaponization, and a lack of available protectivecountermeasures.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Aug 04, 2021
- Source ID
- HDTRA12010015
Entities
People
- Steven Bradfute
Organizations
- Defense Threat Reduction Agency
- University of New Mexico