Based upon the 30,000 cases of culture-confirmed salmonellosis that are reported each year, the Centers for Disease Control and Prevention (CDC) estimates that 1.4 million cases of salmonellosis occur annually in the United States . Though the vast majority of Salmonella infections in the United States is food borne, a significant portion of infections are associated with contact with animals, including pets.  Clinicians should routinely counsel immunocompromised patients and parents of young children about potential risks associated with pets and animal exposures, including salmonellosis.

Public Health-Seattle & King County receives more than 200 reports of culture confirmed salmonellosis each year.  From 2000 to 2005, we received reports of 1,372 cases of culture confirmed salmonellosis, of which, 103 (7.5%) were associated with animal contact. Seventy-eight of these cases were associated with reptiles, 9 with live farm animals (other than poultry), 7 with live poultry, 4 with cats, 4 with dogs, and 1 with a pet hedgehog. Thirty-three of these cases occurred in children aged 5 or younger.

Snakes (and Other Reptiles)

The CDC estimates that 50 to 90 percent of reptiles are infected with salmonella (though reptiles do not become ill), and recommends that reptiles not be kept as pets in households where children under the age of 5 reside. A recent case of snake associated salmonellosis illustrates the danger:

In mid-February, a King County hospital reported that a hospitalized toddler had been diagnosed with Salmonella group B infection. During the epidemiological investigation Public Health learned that three other children in the household also had symptoms of salmonellosis. The toddler also suffered from an underlying chronic medical condition, (another risk factor for severe salmonellosis) and as a result of the salmonella infection, developed severe hemorrhagic diarrhea, requiring administration of red blood cells, platelets and fresh frozen plasma, resulting in a 9-day hospitalization.

Stools from the three children, plus a corn snake kept as a pet by a teenaged sibling (who also became sick but was not tested) tested at the Public Health Laboratory were positive for salmonella group B. The serotype was identified as S. Tyhimurium ; the pulsed field gel electrophoresis (PFGE) patterns for these isolates were indistinguishable.

The mother reported that the ill children never had direct contact with the corn snake, and the snake was not allowed to roam free in the house. However, the week prior to the first child’s onset, the mother and teenager had cleaned the tank of the corn snake with a household broom that was subsequently used in the kitchen and other areas of the house without being cleaned and disinfected.

Although the mother was aware that reptiles pose a risk for salmonella infection, she was not aware that just having a reptile in the home was a risk. Though some pet stores in King County voluntarily give out information on the risk of salmonellosis when they sell a reptile, (which is recommended), this corn snake was purchased through the internet.

Chicks (and Ducklings)

Another type of pet that has been associated with salmonella infections (especially relevant as we move into spring and Easter season) are baby chicks and ducklings. Over the past decade, five salmonellosis outbreaks have been associated with handling chicks or ducklings in the United States . One of the largest outbreaks affected over 22 residents of Washington and Oregon , and half of the patients were younger than 13 years old.

The Washington State Department of Health has developed educational materials with the prevention message, “After You Touch a Duck or Chick, Wash Your Hands So You Don’t Get Sick”. Flyers, posters, and duck and chick stickers with this slogan are available at their website: www.doh.wa.gov/ehp/ts/Zoo/salmonellachick.html

Hamsters (and other Rodents)

Rodents, such as hamsters, mice, and gerbils are also able to transmit salmonella infection to humans. In 2005, the CDC investigated 15 multidrug-resistant S. Typhimurium infections that had occurred during 2003 and 2004 in persons who had either primary or secondary contact with hamsters, mice, rats, or gerbils. Eight of these children were age seven or younger.

Health care providers should be aware that the CDC recommends that infants and children under 5 years old avoid contact with reptiles, amphibians, baby chicks, ducklings, and petting zoos. Children under age 5 who are medically fragile are especially susceptible to severe infection, and parents of these children should be especially warned of the danger of having these pets in the household.

www.cdc.gov/healthypets/diseases/salmonellosis.htm