Inactivated virus vaccine (made with strain TC-83)
o administered in two doses with an interval of 2–4 weeks between doses
o annual revaccination is recommended
o Directions for use provided with commercial products should be followed
Formalin-inactivated virulent VEE virus preparations should never be used in equids
o residual virulent virus can remain after formalin treatment, and thereby cause severe illness in both animals and humans.
o epizootics of VEE have been attributed to the use of such formalin-treated viruses