Ugh. That's no fun!! Yes, the fishzole works the same. Don't take my advice as medical, but can speak from experience.
Every dog is different too. Some dogs are never bothered, where some are very prone to it.
There is a vaccine for it also.
Now that you have the dosage for your dog, I recommend keeping it on hand. Some vets once you've been prescribed are good about giving you another RX, with a phone call, since the labs were recent.
I also use Purina flora probiotic, one pack with each feeding. I've never experienced the continued contamination, but guess it's possible.
I hope your pup feels better.