Can dog's get worm's by smelling other dog's poop?

Depends on a few factors. While sniffing, the dog would need to come in contact with the poop, meaning their nose would need to touch it. The eggs could connect with the nose and the dog would then lick their nose and be contaminated.

Sniffing is not generally how a dog transmits disease or worms. There normally must be contact. Tasting, licking direct contact.

If you thought this was possible, it is a good idea to re-worm. However, OTC wormers do not work. Especially since there are so many different times of worms and you would need to have a prescription wormer to clean their systems out of any they may have gotten.

No. "Smelling" the poop is not contagious. However, if you see signs of worms in your dogs poop, take a small fecal sample to your vet so the proper worm(s) can be identified. Please treat your dog for worms.

Yes.

Now everyone and ALL the pets have to take worm pills.

All of you should take the medicine at the same time.

yes, diseases and things in poop are very contagious. Get your dog treated.

yep

I think it is only what they eat.