Boehringer Ingelheim has put together some helpful information to keep in mind:

Vaccination is one of the main pillars of a health maintenance program for horses.  Keeping performance horses healthy can be especially difficult because you can’t always control their risk of exposure to the microbes that cause illness in horses.  Because they often have challenging performance, training and travel schedules, performance horses may be particularly at risk of infectious disease.

Vaccinating horses has several benefits.  Most people understand that vaccination will increase the horse’s immunity and resistance to specific microbes that could cause illness.   Vaccinated horses are less likely to become sick if they are exposed to infectious microbes. Even if they do get sick they tend to be less severely affected and they recover sooner.  There is an additional benefit to vaccination. Even if vaccinated horses get infected, they tend to shed less of the disease-causing microbe than unvaccinated horses. That means they represent less of a risk to other horses than if they were not vaccinated. So vaccinating horses also helps protect a group of horses. That is the reason why veterinarians may recommend vaccination even if an outbreak has already started.

The American Association of Equine Practitioners publishes and regularly revises vaccination recommendations for horses. They divide their recommendations into two categories, core and ‘risk-based’.  The core diseases tend to be for diseases where there is a high risk of severe disease or where there is a risk to public health from a sick horse.  These also tend to be diseases where vaccines have been shown to provide excellent protection.  The core diseases are tetanus, eastern and western equine encephalitis, West Nile virus and rabies. 

Risk-based diseases are a combination of diseases that are either not widespread or where the risk or consequences of exposure is not the same for all horses. These diseases include equine influenza and equine herpes (‘Rhino’) along with several others.  Veterinarians may decide that ‘risk-based’ diseases should actually become core for horses that have a high risk of becoming infected or for horses that are at high risk of being severely impacted if they did become sick.

Boehringer Ingelheim has a long history of developing and manufacturing vaccines.  Some of its most recent products are Calvenza® and the Vetera™ family of vaccines.  Calvenza® is an effective and versatile vaccine to protect horses against equine influenza and equine herpes viruses.  Calvenza® can be given either by injection into the muscle or with an intranasal applicator.  It contains multiple strains of equine influenza virus and is the only vaccine sold in Canada that contains the strain, Ohio ’03.  It is also the only vaccine sold in Canada claiming protection against flu lasting at least 12 months.

Vetera™ is actually a family of vaccines consisting of different combinations of West Nile, eastern and western encephalitis, equine influenza and equine herpes virus along with tetanus.   Vetera™ incorporates the most current isolate of West Nile virus available in a vaccine.  It has been proven to provide at least 12 months of protection against West Nile Virus.