Changes

*Venezuelan EEV.<ref name="multiple">Bertone, J.J (2010) Viral Encephalitis in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), ''Saunders'', Chapter 12</ref>

*Venezuelan EEV.<ref name="multiple">Bertone, J.J (2010) Viral Encephalitis in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), ''Saunders'', Chapter 12</ref>

Eastern EEV has North and South American antigenic variants.  Western EEV is a recombinant between an Eastern EEV-like virus and a Sindbis-like virus.  Western EEV also has two antigenic subtypes - WEE and Highlands J viruses.  Considerable overlap exists between the various strains in terms of their geography, and potentially also in their antigenic properties and biological behaviour.  Of the 6 subtypes of Venezuelan EEV (I-VI), significant outbreaks of equine encephalitis in the Western Hemisphere over the last two decades have been caused by IAB, IC and IE.  Variant ID from Central America and variant IF from Brazil are considered endemic and typically demonstrate low pathogenicity for horses.  These features are also typical of subtype II (Everglades) virus in Florida and types II, IV, V ad VI viruses.<ref name="multiple">Bertone, J.J (2010) Viral Encephalitis in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), ''Saunders'', Chapter 12</ref>

Eastern EEV has North and South American antigenic variants.<ref> Casal, J (1964) Antigenic variants of equine encephalitis virus.  ''J Exp Med'' 119:547-565.  In: Bertone, J.J (2010) Viral Encephalitis in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), ''Saunders'', Chapter 12.</ref> Western EEV is a recombinant between an Eastern EEV-like virus and a Sindbis-like virus.  Western EEV also has two antigenic subtypes - WEE and Highlands J viruses.  Considerable overlap exists between the various strains in terms of their geography, and potentially also in their antigenic properties and biological behaviour.  Of the 6 subtypes of Venezuelan EEV (I-VI), significant outbreaks of equine encephalitis in the Western Hemisphere over the last two decades have been caused by IAB, IC and IE.  Variant ID from Central America and variant IF from Brazil are considered endemic and typically demonstrate low pathogenicity for horses.  These features are also typical of subtype II (Everglades) virus in Florida and types II, IV, V ad VI viruses.<ref name="multiple">Bertone, J.J (2010) Viral Encephalitis in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), ''Saunders'', Chapter 12</ref>

===Diseases===

===Diseases===