Control Measures on a Commercial Farm
The aim of any control program for BoHV-1 should aim to reduce the circulating virus in sero-positive herds by vaccination and prevent the introduction of the virus onto the farm through strict biosecurity.
Reduce circulating virus in a herd
Reduction of circulating virus can be achieved with the introduction of a vaccination program and progressive culling of those animals that are identified as a potential source of the virus. In farms with a very low sero-prevalence culling without vaccination can be an option however in most farms due to the high sero-prevalence it is not economically feasible to test and cull al the sero-positive animals.
BoHV-1 vaccination
With the development of BoHV-1 marker vaccines, non-marker BHV-1 vaccines should not be used as it makes the process of control and eradication incompatible.
Animals should be vaccinated twice a year. It is common practice to vaccinate at the beginning of autumn when housing of animals takes place and then at spring.
The use of live vaccines is preferred above the inactivated ones because of the superior efficacy in clinical protection and more importantly in reduction of the virus circulation.
Prevention the of introduction BoHV-1 onto a farm
Biosecurity
It is extremely important to establish efficient biosecurity measures in particular adequate quarantine periods.
Quarantine
Effective quarantine prevents the introduction of animals that are infected with or incubating BoHV-1. Replacement animals for the farm should be sourced from herds that are free of the disease but nevertheless such animals should be submitted to a period of quarantine during which they should be tested for BoHV-1 and observed for the presence of any clinical signs. Paired serology with a 3-week interval should be performed.
Animals that are sero-positive for BoHV-1 should never been introduced onto the farm as they must be regarded as lifelong potential shedders of the virus.
Visitors
- Kept to a minimum
- Should be provided with boots and overalls
- Shower facilities
- Foot baths
Cars/Feed lorries
- Parking for vehicles outside the farm
- Wheel-baths
Dead animals
- Dead animals should be placed outside the farm if they are going to be collected by a disposal service.