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Herd Immunity

What is Herd Immunity?

Your horse is part of a herd whether this is their field companion, the other horses on the yard or even the other horses in your local area. The impact of this is that your horse may be at risk of picking up an infectious disease even if it doesn’t leave home and will contribute to the spread of this to other susceptible horses.

Herd immunity is a form of immunity that occurs when the vaccination of a significant portion of a herd provides a measure of protection for individuals who have not developed immunity.  In these situations the disease is unable to spread because there are too few susceptible horses left to propagate the outbreak.

In Britain it is estimated that less than 50% of horses are vaccinated for ‘flu’ but this needs to be considerably higher to achieve herd immunity and provide better protection for Britain’s horses.

Herd immunity is also important with other infectious diseases such as strangles and herpes. A greater uptake of vaccination against these diseases will provide better protection for both the individual animal and our local and national herd.

How vaccination increases herd immunity in horses from Keep Britain's Horses Healthy on Vimeo

What should I do now? 

  • Check your horses vaccination status
  • Ask yourself - Is my horse at risk of disease? Is my horse putting other horses at risk of disease?
  • Discuss a suitable vaccination protocol with your vet
  • Discuss yard protocols for new arrivals and what to do in the event of a possible disease outbreak with the yard manager.

Where can I go for further information?

Horse health categories: 

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Is your vet onboard?

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