title: An outbreak of staphylococcal food poisoning caused by enterotoxin H in mashed potato made with raw milk.
abstract: Mashed potato made with raw bovine milk was suspected to have been the source of a food poisoning outbreak. Almost 8 x 10(8)Staphylococcus aureus CFU g(-1) were detected in the mashed potato. S. aureus was also found in bulk milk from the farm that had supplied milk for the mashed potato. Isolates from mashed potato and bulk milk were positive for the gene encoding staphylococcal enterotoxin H (seh), and the corresponding protein toxin, SEH, was detected by ELISA in the mashed potato. Production of SEH by S. aureus isolates from mashed potato (n = 4) and bulk milk (n = 4) was also demonstrated by ELISA. Sequencing of seh from one mashed potato isolate and one bulk milk isolate confirmed that the gene was a variant seh, and that the genes in both isolates were identical. Macrorestriction of chromosomal DNA with Sma1 followed by pulsed-field gel electrophoresis of seh-positive S. aureus from mashed potato and bulk milk revealed indistinguishable banding patterns between isolates from both sources. It seems likely that raw bovine milk used in the preparation of mashed potato contained S. aureus that subsequently produced sufficient SEH in the mashed potato to cause food poisoning.
authors.affiliation: Department for Feed and Food Hygiene, National Veterinary Institute, Oslo, Norway.
authors.forename: Hannah J
authors.initials: HJ
authors.lastname: Jørgensen
authors.forename: Tone
authors.initials: T
authors.lastname: Mathisen
authors.forename: Astrid
authors.initials: A
authors.lastname: Løvseth
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Omoe
authors.forename: Kristina S
authors.initials: KS
authors.lastname: Qvale
authors.forename: Semir
authors.initials: S
authors.lastname: Loncarevic
mesh_terms: D000328:Adult; D000818:Animals; D002417:Cattle; D002648:Child; D002675:Child, Preschool; D002876:Chromosomes, Bacterial / Q000235:genetics / Q000378:metabolism; D015169:Colony Count, Microbial; D016172:DNA Fingerprinting; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D015252:Deoxyribonucleases, Type II Site-Specific / Q000378:metabolism; D004196:Disease Outbreaks; D016521:Electrophoresis, Gel, Pulsed-Field; D004768:Enterotoxins / Q000032:analysis / Q000235:genetics / Q000302:isolation & purification* / Q000633:toxicity*; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D008892:Milk / Q000382:microbiology*; D017720:Molecular Epidemiology; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D017422:Sequence Analysis, DNA; D011198:Solanum tuberosum / Q000382:microbiology*; D013202:Staphylococcal Food Poisoning / Q000453:epidemiology*; D013211:Staphylococcus aureus / Q000302:isolation & purification* / Q000378:metabolism
chemical_list: D004269:DNA, Bacterial; D004768:Enterotoxins; C402489:Staphylococcal enterotoxin H; C025651:CCCGGG-specific type II deoxyribonucleases; D015252:Deoxyribonucleases, Type II Site-Specific