Changes

====Control====

====Control====

=====Vaccination=====

=====(1) Vaccination=====

Most vaccines are killed (produced in cell culture and inactivated with formalin) and elicit significant increases in Ab titre after 3 days.  Protective titres last for 6-8 months.  Some cross-protection is seen between the serotypes but not between Western and Eastern EEV.  Monovalent, divalent and trivalent vaccines are available but the response to monovalent VEE vaccination is decreased in horses previously vaccinated against WEE and EEE.  The current recommendation is to vaccinate susceptible horses annually in late spring or several months before the high risk season.  Biannual or triannual vaccination should be employed in regions where the vector season is prolonged. Susceptible horses should also be vaccinated in the face of an outbreak.  Mares should be vaccinated one month prior to foaling to boost colostral-derived Ab, which persists for 6-7 months.  Although foals can be vaccinated at any time, early vaccination should be followed by boosters at 6 months and at one year.  Vaccination does not interfere with the ELISA assay for VEE.  '''''PRECAUTION'': human vaccination is recommended for vets in endemic areas'''.

Most vaccines are killed (produced in cell culture and inactivated with formalin) and elicit significant increases in Ab titre after 3 days.  Protective titres last for 6-8 months.  Some cross-protection is seen between the serotypes but not between Western and Eastern EEV.  Monovalent, divalent and trivalent vaccines are available but the response to monovalent VEE vaccination is decreased in horses previously vaccinated against WEE and EEE.  The current recommendation is to vaccinate susceptible horses annually in late spring or several months before the high risk season.  Biannual or triannual vaccination should be employed in regions where the vector season is prolonged. Susceptible horses should also be vaccinated in the face of an outbreak.  Mares should be vaccinated one month prior to foaling to boost colostral-derived Ab, which persists for 6-7 months.  Although foals can be vaccinated at any time, early vaccination should be followed by boosters at 6 months and at one year.  Vaccination does not interfere with the ELISA assay for VEE.  '''''PRECAUTION'': human vaccination is recommended for vets in endemic areas'''.

=====Vector control=====

=====(2) Vector control=====

Responsible use of insecticides and repellents, elimination of standing water, and stable screening will all help to reduce viral transmission.  Environmental application of insecticides may be useful in endemic areas or during an outbreak.  Horses infected with Venezuelan EEV should be isolated for 3 weeks after complete recovery.

Responsible use of insecticides and repellents, elimination of standing water, and stable screening will all help to reduce viral transmission.  Environmental application of insecticides may be useful in endemic areas or during an outbreak.  Horses infected with Venezuelan EEV should be isolated for 3 weeks after complete recovery.