Firstly, as soon as clinical signs or risk are suspected, all equine animals on the premises should be swabbed (see diagnosis) to confirm or rule out EI infection and to clarify those that are actively shedding virus. It may then be possible to manage infected/ shedding and non-shedding horses into isolated groups to minimise the risk of spread to those that are not yet infected. On studfarms, in particular, not yet infected pregnant mares and mares with foals at foot should be managed separately from the infected group, to try to avoid infection of their foals, who may become more seriously ill (see clinical signs). Stallions should be housed and managed separately from mares and, if not yet infected, biosecurity measures should be in place to avoid their direct or indirect contact with infected mares or other horses.
Vaccinated horses should be additionally vaccinated, if they have not been booster vaccinated within the last 6 months and even if they have, there is research evidence to suggest that additional vaccination may be helpful in controlling an outbreak of EI.
The health and welfare of infected animals should be specifically addressed by the attending veterinary surgeon until recovery from all clinical signs and repeat swabbing confirms no further shedding of virus, demonstrating that all horses are no longer actively infected.