1. Tracking Down Salmonella in a Rodent Breeding Facility Carol M. Davis, MSPH Epidemiologist Texas Department of State Health Services Health Services Region 7

2. A Cluster of Cases Minnesota Department of Health identified 4 cases of Salmonella typhimurium with indistinguishable PFGE patterns tested between December 2005 & January 2006 3 were from the same junior high 1 had a sibling in the implicated junior high All cases were interviewed and asked about food consumption, animal contact and other high risk activities The initial investigation implicated a snake in the science classroom Environmental samples were collected from the classroom in March 2006: snake, cage, countertops, frozen feeder mice Minnesota checked PulseNet to see if there were any additional cases

3. Pulse Net PulseNet is a national network of public health and food regulatory agency laboratories coordinated by the Centers for Disease Control and Prevention (CDC). PulseNet participants perform standardized molecular subtyping (or “fingerprinting”) of foodborne disease-causing bacteria by pulsed- field gel electrophoresis (PFGE). Patterns are submitted electronically to a database at the CDC. Participants can then compare their pattern with others across the nation. http://www.cdc.gov/pulsenet/ Escherichia coli O157:H7 Salmonella Shigella Listeria Campylobacter

4. The Cluster Expands The pattern from this Salmonella typhimurium cluster is fairly rare.2% of S. typhimurium in Pulse Net from 1996 – Jan 2006 PulseNet reveled additional matching cases in 6 states Each state was asked to look for recent exposure to reptiles or rodents ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Two other states had cases with documented reptile/rodent exposure Pennsylvania's case March 2006: case tested + for S. typhimurium S. typhimurium isolated from frozen rodents fed to pet reptiles Michigan’s case May 2006: case tested + for S. typhimurium S. typhimurium isolated from a pet reptile

5. The Link to Texas Junior High in Minnesota Pennsylvania Case Michigan Case Online Frozen Rodent Supplier in Texas

6. The Link to Texas DSHS Region 7 received a call in May 2006 Multiple conferences calls held with State and Federal partners No human cases were identified in Texas Field investigation was initiated on May 16

7. Questions Who has legal authority to inspect the facility? Who has legal authority to shut the facility down (if needed)? Where is the facility actually located? What is the connection between this facility and similar ones elsewhere in Texas? Is a Salmonella infected/contaminated mouse considered an adulterated product? Whose jurisdiction does the investigation belong to?

8. Whose Jurisdiction?  Texas Department of State Health Services Public health agency with authority over human health issues  Texas Animal Health Commission Regulatory agency responsible for the health of Texas livestock  US Food and Drug Administration Federal agency regulating manufacture and distribution of food additives and drugs to be given to animals  US Department of Agriculture Federal agency responsible for administering the animal welfare act  (Texas) Office of the State Chemist Regulatory agency over feed and fertilizer products in Texas

9. The Field Investigation Team DSHS – Public health concerns Feed & Fertilizer – Texas animal feed regulations FDA – Interstate commerce concerns Office Of The Texas State Chemist Feed and Fertilizer Control Service

10. The Facility

11. Methods Is the facility a public health hazard? How many employees work there? Does the public have access to it? Has anyone been ill there or in the area? Is Salmonella present in the facility? Environmental Sampling If Salmonella is present, is it linked to the human cases in Minnesota? Laboratory analysis

12. Sampling Design 2 buildings with a total of 3 rooms Largest room: 263- 313 cages

13. Sampling Tools SpongeSicle Used on large surface areas Cary-Blair Medium Swabs Used for smaller or harder to reach places Scoops Collects large amounts of material (shavings, feed, etc)

14. Sample Collection Each sample was marked with a unique identifier Collection method, time, collected by and notes were recorded for each sample SampleMethodTimeBy Notes A12C9:45GT D34S9:50GT 2 dead E26C10:00GT G35S10:05GT 3 ill H65S10:10GT under vent I11C10:25GT

15. Results Room Total Cages Cages Sampled Positive Cages Comments I mostly rats 263 - 31381 Positive from the only mice tray sampled in room II all mice 14693 Room had a total of 5 positive specimens (1 from the vent and 1 tray had both shavings and SpongeSicle™) III all rats521Only positive rat tray sampled 49 environmental samples collected by DSHS Region 7 - (7 +) 4 unfrozen mice collected by DSHS Region 7 - (0+) 13 frozen rats and 55 frozen mice collected by the Feed and Fertilizer - (1+) 1 water and 6 feed samples collected by DSHS Region 7 - (0+)

16. Results Summary of Positive Results RoomIdentifierMethodComments II24Scoop of ShavingsOnly mouse cage sampled in rat room IIN64SpongeSicleCage located under the + vent IIS21SpongeSicleDead mouse seen in cage IIT32Scoop of Shavings5 dead mice in cage IIT32SpongeSicleSame cage as above IIM-VentCary BlairAC vent directly over cage N64 IIIW00Scoop of ShavingsOnly + rat cage sample N/A#25Whole Rodent Frozen adult mouse collected by TX Feed & Fertilizer

17. Linking it Back to Minnesota PFGE results were compared to Minnesota through PulseNet. XbaI is the primary restriction enzyme. Preliminary results indicate all of TX's samples are apparent two enzyme matches to each other and to those from Minnesota (MN).

18. Recommendations Made Handling information and health risk disclaimer needed for product sold to customers Increase hand washing and improve sanitation at the facility Warning labels placed on all product Product used for reptile/raptor food only Isolate ill rodents – do not sell

19. Acknowledgements DSHS Region 7 Glenna Teltow Yolanda Holmes James Morgan, MD Beverlee Nix, DVM Russ Jones Debbie Shelton DSHS Central Office Ernest Oertli, DVM Tom Sidwa, DVM Linda Gaul, PhD Ana Marie Valle-Rivera, PhD Eric Casey Monica Kingsley Chris Malota DSHS Region 3 Shelley Stonecipher, DVM Office of the State Chemist Ben Jones Brent Sexton* US Food and Drug Administration Grant Davis* Ricky Rodriguez Tarrant County Health Department Centers for Disease Control and Prevention Chris Braden, MD Minnesota Department of Health Candace Fuller Texas Veterinary Medical Diagnostic Lab Gayne Fearneyhough, DVM http://www.dshs.state.tx.us/idcu/data/Annual/2000s/2006/ Zoonoses and Public Health 55(2008) 481-487