Can a Dog Pass an Intestinal Infection to a Human?

Wash your hands after petting Pluto to reduce the risk of contracting intestinal infections from your dog.
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Zoonotic diseases or infections originate from infectious agents capable of spreading between species, such as between dogs and humans. When you share licks and kisses with your canine companion, you could be contracting germs or parasites that can cause you various intestinal infections. Most infections spread through contact with infected feces,, not smooching your dog, so regular hand-washing after contact with the dog helps to reduce your risk.

Salmonella

Salmonella commonly transmits to humans and dogs through ingestion of contaminated food. However, this zoonotic pathogen can spread from dogs to humans through contact with infected feces or bedding. Your dog passes salmonella through his feces, and then can spread it to his body after licking a contaminated paw and then his fur. Simply petting your dog and not washing your hands after exposure and before eating is enough to spread the pathogen. Symptoms include diarrhea, fever and abdominal cramps.

Giardiasis

Giardiasis is an intestinal infection caused by Giardia intestinalis. Similar to salmonella, Giardia spreads through contact with infected feces and poor hygiene. Symptoms in dogs include diarrhea, vomiting and weight loss. In humans, symptoms include diarrhea, greasy stools, gas, upset stomach, abdominal cramps and dehydration.

Cryptosporidiosis

Cryptosporidiosis is an intestinal infection caused by the Cryptosporidium parasite. This parasite enters your dog’s body through the ingestion of contaminated water, food or feces. Again, the spread of this condition is through the fecal-oral route, meaning contact with infected feces and poor hand-washing prior to eating. Symptoms in your dog include fever, diarrhea, lethargy and weakness. In humans, symptoms include dehydration, weight loss, stomach cramps, fever, nausea and vomiting.

Campylobacteriosis

Campylobacteriosis is an intestinal infection caused by Campylobacter jejuni or Campylobacter coli. Typically spread to humans through the ingestion of contaminated foods, campylobacteriosis can spread through contact with contaminated feces and poor hand-washing. Dogs do not need to have symptoms in order to spread the bacteria through their feces. Symptoms in humans include watery or bloody diarrhea, abdominal cramps, nausea, vomiting and fever.

Worms

Common intestinal infections that can spread from dogs to humans include roundworms and hookworms. These intestinal worms spread through feces. Eggs shed in the feces and infect the soil. Children who play outside in the dirt are often at greatest risk for contracting roundworm. As they play, they have a tendency to put objects or dirty hands in their mouth, potentially ingesting eggs. Hookworms can penetrate the skin and are often picked up by walking barefoot in contaminated soil. Often, you can see these worms in feces. The best way to prevent infection is to pick up and dispose of feces regularly. Symptoms in dogs include diarrhea, vomiting, weight loss, swollen abdomens and anemia. In humans, symptoms include intestinal discomfort, blindness and itchy skin rashes.