Impact of Invalid Salmonella Laboratory Testing Methods on Global Public Health

Monday, June 5, 2017: 4:20 PM
400A, Boise Centre
Megin Nichols , Centers for Disease Control and Prevention, Atlanta, GA
Kelly J. Gambino-Shirley , Centers for Disease Control and Prevention, Atlanta, GA
Lauren Stevenson , Centers for Disease Control and Prevention, Atlanta, GA
Byron Schick , Animal and Plant Health Inspection Service, USDA, Oklahoma City, OK
Linda Schlater , Animal and Plant Health Inspection Service, USDA, Ames, IA
Tom Gomez , Animal and Plant Health Inspection Service, USDA, Atlanta, GA

BACKGROUND: In 2015, the Centers for Disease Control and Prevention (CDC) received a report of a child who developed a Salmonella gallbladder abscess following contact with a small turtle (shell length <4 inches) purchased at a flea market; a federal ban prohibits sale of small turtles in the United States. Federal regulators visited the flea market and interviewed the turtle vendor who reported obtaining turtles from Turtle Farm X in Louisiana (LA). In 2015, Turtle Farm X and other LA turtle farms exported turtles internationally. Salmonella illnesses linked to small pet turtles were reported to the CDC by countries importing turtles from Turtle Farm X.

METHODS: At the time of these reports, LA state law required Salmonella-negative test results before export. Additionally, some countries importing turtles from the United States required a Salmonella-negative test result and a signed US Department of Agriculture health certificate for imported turtles. We investigated Salmonella testing practices and results for turtles exported from Turtle Farm X.

RESULTS:  We discovered that Turtle Farm X utilized Laboratory Z, exclusively, for Salmonella testing. Laboratory Z was not registered as a business in LA. Examination of Laboratory Z’s official reports revealed that the laboratory’s name in the heading of the reports included the word “Diagnostic,’ misspelled as “Diganostic.” This error raised suspicion that Laboratory Z might not be a legitimate laboratory. The authority overseeing the LA turtle industry found that testing methods utilized by Laboratory Z were outdated and inadequate to detect Salmonella. When valid testing methods were used at accredited veterinary laboratories, Salmonella was isolated from turtles exported from LA. Louisiana law required negative test results as a condition of export; therefore, turtles could not be exported. In April 2016, <6 months after the outbreak investigation was initiated, an emergency change of LA administrative rules was issued eliminating testing of turtles for Salmonella as a condition of export unless required by the importing country.

CONCLUSIONS:  Invalid laboratory methods and reports certifying that animals tested negative for Salmonella has contributed to illnesses in the United States and other countries. When contaminated food products are exported and cause illnesses, recalls occur and countries might cease product imports. Small turtles are often linked to illnesses and cannot be rendered Salmonella-free, and their sale is therefore banned in the United States. Allowing exports of small turtles puts purchasers in other countries, especially children, at a risk deemed unacceptable in this country.