Public Health Impact of Feeder Rodents Used As Feed for Pet Reptiles, a Review of U.S. Food and Drug Administration Data, 2005 - 2013

BACKGROUND: Of the estimated 1.2 million human infections of Salmonella each year in the United States approximately 11% are due to contact with animals and their feed.  Outbreaks of human salmonellosis following exposure to Salmonella-contaminated pet foods have been previously investigated; however, those illnesses were typically due to exposure to dry pet food and treats.  Since 2006, the Food and Drug Administration (FDA), Centers for Disease Control and Prevention, and various states have investigated 6 confirmed or suspected human salmonellosis outbreaks that have been due to exposure to frozen feeder rodents used as animal feed for pet reptiles. 

METHODS: The Coordinated Outbreak and Response Evaluation (CORE) group within FDA reviewed an internal database for any human illness outbreaks due to exposure to feeder rodents during the time period 2006 through 2013.  Data were obtained during state and federal investigations and available to CORE. 

RESULTS: A total of 6 outbreaks were identified (1 each in 2006, 2009, 2010, and 2011; and 2 in 2013) resulting in ≥625 laboratory-confirmed Salmonellaillnesses and 10 hospitalizations; no deaths were reported.  Ages of cases ranged from 1 month to 77 years.  The 2006 multi-state outbreak involved school-age children with classroom exposures to snakes and frozen mice purchased from an internet-supplier in Texas; state and federal officials conducted a joint inspection at the feeder rodent breeding facility.  The largest outbreak, in 2009, resulted in over 500 human illnesses in the United Kingdom; the implicated feeder rodents were sourced from a U.S. firm.  The 2010 outbreak was a continuation of the 2009 outbreak; a joint FDA / state inspection at the feeder rodent breeding facility in Georgia resulted in a voluntary recall of the implicated frozen feeder rodents.  The remaining outbreaks did not result in any federal regulatory activity. 

CONCLUSIONS: Investigations into the outbreaks associated with exposure to frozen feeder rodents identified gaps in the feeder rodent industry.  In most of the outbreaks, poor record keeping and product labeling at retail locations and suppliers, as well as repackaging by independent distributors, complicated the ability to trace product and recall it to protect public health.  Public health officials and regulatory agencies at the local, state, and federal levels in the U.S., as well as the pet industry, should work together to develop sufficient mitigation efforts to ensure adulterated product does not enter commerce, thereby preventing human infections from occurring.  If adulterated product does enter commerce, proper labeling should ensure a prompt recall.