Hello again. We have covered a lot of ground so far on how
to protect your horse from parasite and insect infestations.
And now, let's turn our attention to vaccines and the diseases they can prevent.
We'll also look at some of the more common diseases we see as veterinarians.
And by the end of the lesson,
you'll be able to recognize the symptoms of some of
these diseases and have a vaccination plan in place to prevent them.
Before we begin, it's important to know that in veterinary medicine,
much like in human medicine,
we cannot guarantee prevention of a disease
based just on the fact that a horse has received vaccines.
The horse's immune system also plays a large role in how it responds to a vaccine.
Although we don't have time to explain
the details of the horse's immune system in this course,
keep in mind that there are several factors involved in
the horse's immune system that affect how the horse reacts to the vaccine.
The vaccine may not work or there may be
severe immediate reactions if the horse's immune response is not appropriate.
First of all, the vaccine must be produced by a reputable company,
properly shipped and stored,
and properly administered to do its job.
Some vaccines are injected in the muscle,
some under the skin,
and some are sprayed into the nostril.
Some vaccines are given once a year,
some every few months,
and some require multiple initial doses several weeks apart to create lasting immunity.
Your horse must have a healthy immune system to do its job in mounting
a robust response and making antibodies to protect him from the disease.
If too many vaccines are given at once,
it may overwhelm the immune system and your horse will not be protected.
It is possible for a horse to have an adverse or negative reaction to the vaccination,
such as local swelling,
or abscessed formation at the injection site,
transient fever, lethargy, or a severe allergic reaction.
These signs should be evaluated by a veterinarian and
will sometimes be reported to the vaccine company.
That's why we encourage horse caretakers to have a veterinarian plan,
a specific vaccination strategy that includes ordering,
storage, and administration of the vaccinations.
In the unlikely event that your horse has a severe reaction to a vaccination,
your veterinarian will have the medications on hand to optimize treatment and response.
Veterinarians are also likely to keep complete records of horse vaccination history,
this is not only helpful in the event that the horse gets ill,
but also if the horse needs to show, travel or sold.
Next, we'll take a look at some of
the more common diseases that can be prevented with vaccination.
Your veterinarian will advise you which vaccinations are
most appropriate for your horse based on regional diseases,
likelihood of exposure, and the health of the horse.
Let's start with core vaccines likely to be recommended.
These are considered core,
because they are diseases known to exist in
many regions or have potential to infect people.
They can be highly infectious or pose a risk of severe disease.
These vaccines are considered to be relatively
safe with low risk of negative reaction in the horse,
and include tetanus, Eastern and Western equine encephalitis,
West Nile virus, and rabies.
The next category of vaccines are risk based vaccines because as the name implies,
whether or not you choose to use them is determined by the potential risk of
your horse coming in contact with the disease and succumbing to the infection.
These vaccines often include equine influenza,
equine herpes virus which is also known as rhinopneumonitis,
potomac horse fever and strangles.
This list can also include snake bite or rattlesnake vaccine, botulism,
equine viral arteritis, leptospirosis,
rrotaviral diarrhea, and anthrax.
It is also worth pointing out,
protection from the vaccine does not occur immediately after administration.
Full immunity requires the appropriate number of doses given at the proper interval,
and can often take 10 to 14 days to occur.
So, vaccination the day before a trip, is not advised.
Vaccines must generally be given before the horse is
exposed to the disease in order to have full protection.
And remember, as we discussed with parasite control,
good management practices have to be followed.
The vaccination program will not work if there is
repeated and overwhelming exposure to the infectious agents.
A good management plan for controlling infectious disease is called a biosecurity plan.
Biosecurity is a concept we'll explore some,
in depth, in the upcoming lesson.
Claudia Sonder, DVMEmeriti Director of Equine Outreach
