Equine amplification and virulence of subtype IE Venezuelan equine encephalitis viruses isolated during the 1993 and 1996 Mexican epizootics.
Emerg Infect Dis
; 9(2): 161-8, 2003 Feb.
Article
en En
| MEDLINE
| ID: mdl-12603985
ABSTRACT
To assess the role of horses as amplification hosts during the 1993 and 1996 Mexican Venezuelan equine encephalitis (VEE) epizootics, we subcutaneously infected 10 horses by using four different equine isolates. Most horses showed little or no disease and low or nonexistent viremia. Neurologic disease developed in only 1 horse, and brain histopathologic examination showed meningeal lymphocytic infiltration, perivascular cuffing, and focal encephalitis. Three animals showed mild meningoencephalitis without clinical disease. Viral RNA was detected in the brain of several animals 12-14 days after infection. These data suggest that the duration and scope of the recent Mexican epizootics were limited by lack of equine amplification characteristic of previous, more extensive VEE outbreaks. The Mexican epizootics may have resulted from the circulation of a more equine-neurotropic, subtype IE virus strain or from increased transmission to horses due to amplification by other vertebrate hosts or transmission by more competent mosquito vectors.
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Virus de la Encefalitis Equina Venezolana
/
Encefalomielitis Equina Venezolana
/
Enfermedades de los Caballos
Límite:
Animals
País/Región como asunto:
America do sul
/
Mexico
/
Venezuela
Idioma:
En
Revista:
Emerg Infect Dis
Asunto de la revista:
DOENCAS TRANSMISSIVEIS
Año:
2003
Tipo del documento:
Article
País de afiliación:
México