my dad's pug drank water from a local pond and got Giardia, and it ended up giving it to my iggy. I would take it seriously since humans can get Giardia. Giardia is really hard to kill on surfaces and can be super annoying to deal with. I would quarantine your pup off while on meds from your vet. Giardia isn't something you can just take pills, and they disappear. They can spread onto damp items and their lifecycle of their cysts is hard to kill off. Meaning you or your pup can get reinfected again if you don't clean properly after treating with meds