Giardia without diarrhea

[Haley, Yeti, and Phin]

Took Yeti in for a round of shots and a fecal test came up positive for giardia. I am sooo shocked!! His stool has been sooo good for so long. We are picking up our new puppy this weekend (awesome timing huh?) so she is sending us home with some panacur for Yeti and our new babe.
Just curious if we need to do anything along the lines of cleaning inside. Yeti hasn't pooped in our backyard all summer (due to landscaping) so we will have the new puppy go out back.
Do we need to bleach the grass? Do people use straight bleach?
I'm mildly freaking out so any advice is greatly appreciated!

[Karen, Jasper and Jackdoodle]

Haley, ask what kind of test was done. If it was an ELISA Snap test, there can be false positives. The fecal float test is more accurate.  I'd ask if they actually saw giardia cysts or if it was just antigens, which can be present in any dog who's had giardia in the past. 

If he doesn't have any symptoms, I seriously wouldn't worry. And considering how many doodle puppies come home with giardia, maybe it's just as well that you have the Panacur. :) 

[Jane, Guinness and Murphy]

One of my Doodles was also positive for giardia with no symptoms.  I gave one round of Panacur and rechecked, and he came back clear.  I honestly didn't take any of the other precautions that are recommended when they are having diarrhea. 

[Nancy & Echo]

According to the CDC and other websites, bleach is NOT EFFECTIVE in killing giardia on outdoor surfaces. https://www.cdc.gov/parasites/giardia/prevention-control-pets.html

It is certainly possible to be infected with giardia and NOT have diarrhea;  this article from Iowa state says most adult animals with giardia do NOT have symptoms (see p. 7, first sentence under clinical signs). http://www.cfsph.iastate.edu/Factsheets/pdfs/giardiasis.pdf  I  The last update of this article was in 2012.  It also says that its controversial if treatment is needed for asymptomatic animals, and reinfection from the environment is common.  Some studies have suggested that it is more common for animals with diarrhea to have giardia, while other studies have suggested diarrhea is NOT a risk factor for giardia carriage. (P. 9, left column under dogs and cats.)

Also, this article says that cyst shedding is often intermittent.

[Haley, Yeti, and Phin]

Thank you ladies so much! Such a sigh of relief!!