
Dogs —
Roundworm is one of the most common diseases that we get from dogs. Every year there are about 10,000 cases of roundworm spreading through the body and causing fever and fatigue. Dogs and puppies also can transmit campylobacter infections. Symptoms include diarrhea, cramping, abdominal pain and fever.

Cats —
Some of your feline's favorite activities, licking and scratching, can give you the bacterium that causes cat scratch fever, which leads to swollen lymph nodes. Cats also can transmit campylobacter infections, causing symptoms of diarrhea, cramping, abdominal pain, and fever.

Turtles —
About 70,000 people get salmonella infections, typically including fever and diarrhea, from reptiles every year in the US. The bacteria can live on reptiles, like turtles, without making them sick.

Parrot fever can infect parrots, parakeets and macaws, but rarely causes symptoms for them. It can, however, cause fever, chills, headache and pneumonia in people.

Armadillos —
Some armadillos are naturally infected with leprosy, also known as Hansen's disease, according to the Centers for Disease Control and Prevention. It is possible, though unlikely, for humans to catch the disease from armadillos.

Crested gecko —
Since January of last year, the US Centers for Disease Control and Prevention (CDC) reported at least 20 people in the U.S. came down with salmonella infections linked to crested geckos they brought home from pet stores.

Hamsters —
Hamsters and other "pocket pets" can carry lymphocytic choriomeningitis virus (LCMV). The virus typically causes flu-like symptoms, including fever and muscle aches.

Petting zoos —
Petting zoos and county fairs have been associated with outbreaks of E. coli and flu.