title: The key role of pulsed-field gel electrophoresis in investigation of a large multiserotype and multistate food-borne outbreak of Salmonella infections centered in Pennsylvania.
abstract: Five different serotypes of Salmonella enterica were implicated in a large outbreak linked to fresh Roma tomatoes served at gas station deli counters in Pennsylvania and nearby states during July 2004: S. enterica serotypes Javiana, Anatum, Thompson, Typhimurium, and Muenchen. One of these serotypes, Anatum, was isolated from both tomatoes and patients. Pulsed-field gel electrophoresis (PFGE) played a key role in identifying the outbreak-associated isolates and distinguishing them from unrelated sporadic isolates. It also demonstrated that the genetic fingerprints of serotype Anatum isolates derived from patients were indistinguishable from those derived from tomatoes. Rapid communication of PFGE fingerprints with other public health laboratories through the Centers for Disease Control and Prevention's PulseNet USA national molecular surveillance network for bacterial food-borne pathogens facilitated the tracking of this outbreak in other states. The work described in this report emphasizes the laboratory's role in core public health functions and services, thereby providing a highly visible example of public health in action.
authors.affiliation: Molecular Microbiology Section, Bureau of Laboratories, Pennsylvania Dept. of Health, 110 Pickering Way, Lionville, 19353, USA. csandt@state.pa.us
authors.forename: Carol H
authors.initials: CH
authors.lastname: Sandt
authors.forename: Donna A
authors.initials: DA
authors.lastname: Krouse
authors.forename: Charles R
authors.initials: CR
authors.lastname: Cook
authors.forename: Amy L
authors.initials: AL
authors.lastname: Hackman
authors.forename: Wayne A
authors.initials: WA
authors.lastname: Chmielecki
authors.forename: Nancy G
authors.initials: NG
authors.lastname: Warren
mesh_terms: D002487:Centers for Disease Control and Prevention, U.S.; D004196:Disease Outbreaks; D016521:Electrophoresis, Gel, Pulsed-Field / Q000379:methods*; D006801:Humans; D018551:Solanum lycopersicum / Q000382:microbiology*; D010414:Pennsylvania / Q000453:epidemiology; D011159:Population Surveillance; D011634:Public Health; D012478:Salmonella Food Poisoning / Q000453:epidemiology* / Q000382:microbiology; D019779:Salmonella enterica / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D012703:Serotyping; D014481:United States