Lesson 15: Togaviridae

Question 1

is found principally in Atlantic
coastal areas of the USA, Canada, Michigan, the Caribbean Basin and South
America.
 Two distinct lineages, North American (pathogenic group I)
 and South American (Groups IIA, IIB and III)
 The virus is maintained in cycles of infection involving passerine
birds and the irrigation ditch mosquito Culiseta melanura

Answer 1

Eastern equine encephalitis virus (EEEV)

Question 2

Togavirus
> ____and _______ - Genus
>________________________ - nervous disease in horses
 The Venezuelan equine encephalitis (VEE) complex comprises several viral species, divided into six subtypes I to VI

 Subtype 1:
 Subtype II :
 Subtype III:
 Subtype IV:

Answer 2

> Alphavirus and Rubivirus
Venezuelan, Eastern and Western equine encephalitis viruses
 Subtype 1: have 5 serotypes ( AB - F)
 Subtype II : Everglades virus
 Subtype III: Mucambo virus
 Subtype IV: Pixuna virus

Question 3

 Western equine encephalitis virus (WEEV) cycle of infection involves
mosquitoes, mainly Culex tarsalis, and wild birds.
 Horses are infected incidentally and are dead-end hosts, developing
nly low titres of virus in the blood.
 A related virus, Highlands J virus, occurs in the eastern United
States and causes encephalitis in horses rarely.