Annual spring vaccinations are a ritual worth having, but only if you aren’t simply choosing vaccines by habit. A horse’s life circumstances can change enough in the course of a year to necessitate adjustments in his vaccination program. Here are some instances that call for a review, and possible alteration, of your horse’s vaccine routine:

• Geographic relocation. Where you live matters when it comes to vaccines. Diseases that are rare in the Southwest, for instance, may be common in the mid-Atlantic states. Any move that takes you to a significantly different climate, with different pests, calls for a review of your vaccination plan.

• Increased interaction with other horses. If your horse will be traveling to more shows or trail rides this season or if he’s simply moved to a busier boarding barn, his chances of coming across a contagious horse will increase. If your horse is going to be in contact with more horses this year than in the past, he may need an expanded vaccination plan.

• Advancing age. Although it doesn’t happen suddenly, as a horse ages his immune system may need a “boost” of certain vaccines. Research suggests this is especially likely for horses with Cushing’s disease (pituitary pars intermedia dysfunction). If your horse is 15 or older and you haven’t taken a critical look at his vaccination plan in several years, now is a good time to do it.

Your veterinarian will be familiar with disease risks in your area, making her your best resource for determining which, if any, changes are needed in your horse’s vaccination program this year

This article first appeared in EQUUS issue #463, April 2016.