[runningbeat]

My pup first had giardia when I brought him home at 9 weeks. He was treated 2 times with different medications. He also had amemia, found this out by blood work and stool samples.
Now he just turned 4 months and has giardia again.
Yes, I clean up after him everytime, bath him often and spray area with bleach.
Vet told me that some pups don't have a good immunity and that's why they can't fight it, and other pups can.

So my question is, what product can I give him to build his immunity.
Also how long does it take pups to build there immunity,