Pet rodents are a potential source of salmonella, says the CDC, warning people to wash their hands thoroughly after handling hamsters, mice, or rats — or their cages and bedding.

These pets were the source of salmonella in 15 cases of human infection and illness from December 2003 through October 2004, says the CDC. Those cases were reported in 10 states: Georgia, Illinois, Kentucky, Michigan, Minnesota, Missouri, New Jersey, North Carolina, Pennsylvania, and South Carolina.

Six patients were hospitalized; none died. Symptoms included most commonly abdominal cramping (77 percent), fever (67 percent), vomiting (53 percent), and bloody diarrhea (20 percent).

The patients were all exposed to salmonella during the eight days before the illness started, and the salmonella bacteria was resistant to multiple antibiotics (ampicillin, chloramphenicol, streptomycin, sulfizoxazole, and tetracycline), says the CDC.

Young Patients Seen

Patients were 16 years old, on average; eight were 7 years old or younger.

Two of the people became infected and got ill from salmonella through secondary exposure. In other words, they got the infection from someone who acquired their infection from a rodent bought from a retail pet store.

The others acquired salmonella directly from mice or rats bought to feed to pet snakes (seven cases), pet mice or rats (four cases), and pet hamsters (two cases).

For instance, a 5-year-old Minnesota boy fell ill four days after his family bought a pet mouse. The mouse had become lethargic and had diarrhea immediately after purchase. Still, the boy frequently handled it and kissed it, says the CDC.

No common link was seen between the three main implicated pet distributors, which were located in Arkansas, Georgia, and Iowa, says the CDC.

Other Pets Can Also Carry Salmonella

Besides pet rodents, salmonella has also been linked to pet reptiles, chicks, ducklings, kittens, and hedgehogs, says the CDC.

"Each year, an estimated 1.4 million people in the U.S. have salmonellosis, leading to approximately 14,800 hospitalizations and 415 deaths," says the CDC in its Morbidity and Mortality Weekly Report. That includes salmonella from all sources, not just pets.

Salmonella is found in animals' intestinal tracts. It can be transmitted by ingestion of feces, which can occur by eating contaminated foods or having contact with animals or their environments, says the CDC.

Prevention Tips

The No. 1 rule is to wash your hands thoroughly with soap and water after handling rodents or their cages and bedding. Make sure kids do the same, says the CDC.

The CDC offers more tips for reducing salmonella from "pocket pets" (rats, mice, rabbits, gerbils, hamsters, guinea pigs, and ferrets) and rodents bought to feed other animals, such as snakes:

Buy animals that look lively and alert, with glossy coats free of droppings.
Don't buy a pet that shares a cage with other animals that have diarrhea or look sick.

—Always wash hands thoroughly after cleaning up pets' droppings.
—Make sure children wash their hands immediately after handling rodent feces.
—Supervise young children if they clean the pet's cage.
—Don't smoke or eat food while handling your pet.
—Don't handle pets in areas where food is prepared.
—Don't kiss your pet or hold it close to your mouth.

"If your pet dies soon after you buy it, it may have been ill with a disease that could make people sick," says a CDC news release.

Tell the pet store about the animal's death, and clean and disinfect the cage before reusing it, says the CDC.

By Miranda Hitti, reviewed by Brunilda Nazario, MD

SOURCES: Morbidity and Mortality Weekly Report, May 6, 2005; vol 54: pp 429-433. News release, CDC.