Vaccinations in Horses

Vaccination is essential to protect your horses from infectious and/or contagious diseases in the environment. Over time the horse’s immune system level of antibodies gradually declines. Therefore, booster vaccinations are needed at regular intervals. Protection against some diseases such as tetanus and rabies can be accomplished by boosting once a year. Others require more frequent intervals to provide adequate protection.

Vaccinating helps provide protection from a number of important disease most relevant in our South African environment being: Equine Flu, African Horse Sickness, Tetanus, Equine Herpes, Strangles and Rabies.

Just as in humans, vaccination does not guarantee 100% protection. In some situations, immunization may decrease the severity of disease but not prevent it completely. This is due to many reasons such as differences in the type or severity of some diseases (such as influenza) and mutations of viruses.

Many vaccines require special handling and storage for efficacy. For instance, a particular vaccine may require protection from extremes of temperature or exposure to light to preserve its effectiveness. This is where you can rely on your veterinarian to store and handle the vaccine properly and to make sure that the vaccine has not passed its expiry date.

Vaccination and competition

The FEI stipulates that all horses be vaccinated against equine flu and South African law requires vaccination against horse sickness. Failure to vaccinate and have the vaccinations properly recorded and signed off by a vet in the horse’s passport will mean a horse cannot compete.

Core Vaccines

These vaccines are compulsory and required by law or by equine sports bodies for competition.

Equine Influenza

You can check if your influenza vaccinations are up to date by using our handy Influenza Vaccination App.

Influenza is one of the most common respiratory diseases in the equine. The virus is highly contagious and can be spread from equine to equine over distances as far as 30 meters by snorting or coughing, through saliva and mucous. The risk of influenza is higher for young horses than older horses but is usually not fatal.

Symptoms are similar to those in a human with a cold, i.e., dry cough, nasal discharge, fever, depression, and loss of appetite.

2 vaccinations given 4 – 6 weeks apart, with a first booster within 7 months of the 2nd vaccination of the primary course, thereafter at 6-month intervals and in order to compete must have been vaccinated within the 6 months + 21-day period before the start of the competition and may not compete within 7 days after receiving a vaccination.

African Horse Sickness

Horse Sickness is caused by 9 different serotypes of the virus, borne by the Culicoides midge and is most prevalent in late summer and autumn. It is potentially life threatening and it is up to us as horse owners to vaccinate our horses responsibly and help to grow a national horse population that is largely protected by stronger immunity.

The vaccine is sold as two separate injections, each consisting of different strains of the virus. The first vaccination must be given at least 21 days before the second.

Horses should be vaccinated twice as foals between the ages of 6 and 18 months, not less than 90 days apart and, where possible, between 1 June and 31 October, and thereafter every year between 1 June and 31 October.

A strict African Horse Sickness control policy has been created by the Western Cape government to control the vaccination and movement of horses into and within the AHS Controlled Area. Horses moving in and out of this area need to follow the protocols for correct vaccination and movement needs to be applied for and approved by the local state vet. Movement controls apply to all horses from the AHS infected Zone into the Western Cape Province and within the Western Cape Province from the AHS Protected Zone entering the AHS Surveillance Zone and the AHS Free Area.

Risk based Vaccinations

These are not compulsory but are advised based on the risk posed to the individual horse.

Tetanus

Tetanus is caused by toxin-producing bacteria present in the intestinal tract of many animals and found in abundance in the soil where horses live. Horses are particularly susceptible to the paralyzing toxin produced by the bacterium Clostridium tetani in a wound. Approximately 80 percent of affected horses die but fortunately, this disease is not contagious.

All horses should be immunized with a primary vaccination course of 2 vaccines 4 -6 weeks apart then annually. Fortunately, many of the Flu vaccines also contain a tetanus vaccine, allowing us to provide two vaccines in one.

Equine Herpes Virus (Rhinopneumonitis)

This is particularly a problem in young horses and populations with a high horse turnover. However, the immunity provided is short-lived and requires frequent vaccination to be maintained.

Pregnant mares should be vaccinated during the 5th, 7th and 9th months of gestation using an inactivated EFV1 vaccine, licensed for the prevention of abortion.

Strangles

This upper respiratory disease caused by Streptococcus equi is highly contagious. The strangles vaccine is not a due to a high risk of local reaction and other side effects with the injectable vaccine. The vaccine does not provide long-term immunity, and it should not be given with other vaccinations. Foals may be vaccinated at 2-3 months with a booster 2-3 weeks later.

Rabies

Foals may be vaccinated at 4 months of age with a booster 3-4 weeks later. The rabies shot is given in two initial doses four weeks apart followed by yearly boosters. Vaccination of pregnant mares is not recommended as safety studies have not been performed.

Botulism

Recommended for horses living in close proximity of large-scale pig and chicken farms and where contact with dead birds is likely, or where horses eat poor quality feed, or contamination of pastures is possible.

West Nile Virus

While only 20% of infected horses, and humans, shows signs of infection those that are infected can have highly debilitating and potentially life-threatening disease. It is a good idea to vaccinate valuable horses and those in areas that are known to have cases of severe West Nile Virus.

To plan your vaccination schedule, or discuss which risk-based vaccine may be appropriate for your horse please give us a call and we would be happy to help.