Horse Purchase and Equine Herpes

I am deciding whether to purchase the horse I’m leasing. Her owner disclosed that she contracted equine herpes when she was younger (approximately 4-5 years ago).

Are there any unique considerations when purchasing a horse under these circumstances? Do they require any special care? Is their immune system permanently compromised?

Please note, I have owned horses and ridden for 20+ years. This is not my first horse and though I’ve had a couple of horses whose sole mission was to ensure my vet never missed a light bill, I prefer to avoid a future of vet bills if that is the case here.

Thank you for your input and/or recommendations.

Almost all horses have been exposed to or have had one of the herpes viruses. Seller needs to be more specific about the nature and clinical history of the infection. Anything from a common upper respiratory infection to Neuro or reproductive infection