Can Humans Transmit Stomach Bugs to Dogs? Vomiting & Diarrhea

Yes, some gastrointestinal pathogens can transmit between humans and dogs (zoonotic / reverse zoonotic), but most common viral causes are species-specific.

Transmission Risks

Pathogen	Human → Dog?	Dog → Human?	Notes
Norovirus	Possible (genogroups overlap)	Yes (documented)	Highly contagious; environmental persistence
Rotavirus	Rare	Rare	Species-specific strains mostly
Salmonella	Yes	Yes	Foodborne; reptiles, raw diet risk
Campylobacter	Yes	Yes	Poultry, raw milk, puppy feces
E. coli (STEC)	Yes	Yes	O157:H7; HUS risk in humans
Giardia	Yes	Yes	Assemblages A/B infect both
Cryptosporidium	Yes	Yes	Chlorine-resistant
Canine Parvovirus	No	No	Species-specific
Canine Coronavirus (enteric)	No	No	Species-specific

Prevention When You're Sick

• Hand hygiene: Soap/water 20 sec after bathroom, before pet contact.
• Limit close contact: No face licking, sharing food, sleeping together until 48 hrs symptom-free.
• Separate bathroom if possible.
• Disinfect surfaces (bleach for norovirus/crypto).

If Your Dog Gets Sick

• Withhold food 12–24 hrs (adults); offer small water frequently.
• Bland diet: boiled chicken + rice (2:1) or veterinary GI diet.
• Vet if: Puppy/senior, blood in vomit/stool, lethargy, pain, >24 hrs vomiting, >48 hrs diarrhea, dehydration (skin tent, dry gums).
• Bring fresh stool sample.

Most "stomach flu" in humans is viral (norovirus) and unlikely to severely affect dogs. But bacterial/parasitic GI infections can cross over. Hygiene protects both.