Centers for Disease Control and Prevention (CDC): Guideline for Isolation Precautions: Preventing Transmission of Infectious Agents in Healthcare Settings (2007) CDC: Plague resources for clinicians Other Yersinia Infections Yersinia enterocolitica and Y pseudotuberculosis are zoonoses that occur worldwide and are acquired by ingestion or handling of contaminated food (most commonly raw or undercooked pork products and unpasteurized milk or milk products) or water and occasionally by animal contact.