A Comparison of Salmonella Enteritidis Phage Types From Egg-Associated Outbreaks and Implicated Laying Flocks

Epidemiol Infect. 1993 Feb;110(1):17-22. doi: 10.1017/s0950268800050639.


Infections due to Salmonella enteritidis are increasing worldwide. In the United States, between 1985 and 1989, 78% of the S. enteritidis outbreaks in which a food vehicle was identified implicated a food containing raw or lightly cooked shell eggs. Under a US Department of Agriculture regulation published in 1990, eggs implicated in human food-borne S. enteritidis outbreaks were traced back to the source flock. The flock environment and the internal organs of a sample of hens were tested for S. enteritidis. We compared the S. enteritidis phage types of isolates from 18 human, egg-associated outbreaks and the 15 flocks implicated through traceback of these outbreaks. The predominant human outbreak phage type was recovered from the environment in 100% of implicated flocks and from the internal organs of hens in 88% of implicated flocks we tested. The results support the use of phage typing as a tool to identify flocks involved in human S. enteritidis outbreaks.

Publication types

  • Comparative Study

MeSH terms

  • Animals
  • Bacteriophage Typing
  • Case-Control Studies
  • Chickens / microbiology
  • Disease Outbreaks*
  • Eggs / microbiology*
  • Female
  • Humans
  • Salmonella Food Poisoning / epidemiology
  • Salmonella Food Poisoning / microbiology*
  • Salmonella Phages
  • Salmonella enteritidis / classification*
  • Salmonella enteritidis / isolation & purification
  • United States / epidemiology