DNA Fingerprinting Analysis of Breakthrough Outbreaks in Vaccine-Protected Poultry Stocks▿

We report recurrent outbreaks of Yersinia pseudotuberculosis conjunctivitis in ducks and of fowl cholera in geese, occurring in stocks previously vaccinated with inactivated autogenous vaccines. Enterobacterial repetitive intergenic consensus sequence-based PCR and pulsed-field gel electrophoresis indicated reinfection with a new Y. pseudotuberculosis strain and vaccine evasion by the same Pasteurella multocida strain