title: [Significance of the detection of staphylococcal enterotoxin A gene in low fat milk which caused a serious outbreak of food poisoning].
abstract: In June 2000, there was a large-scale outbreak of food poisoning after consumption of Snow Brand low fat milk. In the evening of a day the incident made public, some cartons of low fat milk were brought to our laboratory for examination. Next day, we detected only staphylococcal enterotoxin (SE) A gene among SE (A-E) genes by PCR in left-over milk samples or samples from the same lots that patients had consumed. We presumed that the outbreak was caused by the intake of SEA. We subsequently confirmed the presence of SEA in these samples. To investigate the existence of SE (A-E) genes in milk, we examined 100 samples of commercial low fat milk and milk by PCR, but none of the genes was detected. We estimated the detection limit of SEA gene in low fat milk by PCR. Four strains of SEA-producing Staphylococcus aureus cultures were serially diluted in low fat milk. The SEA gene was detected at levels of 5.5 x 10(2) to 1.6 x 10(4) cfu/mL of S. aureus. These amounts of S. aureus are higher than the values in raw milk reported previously. Therefore we consider that SE genes in low fat milk should usually be undetectable by our PCR. This study shows that quick detection of SE genes by PCR is very helpful to analyze outbreaks, especially if no significant bacterium can be cultured.
authors: Wakayama City Institute of Public Health: 3-2-67, Matsuehigashi, Wakayama-shi 640-8422, Japan.
authors: Koji
authors: K
authors: Yamashita
authors: Yuko
authors: Y
authors: Kanazawa
authors: Michi
authors: M
authors: Ueno
authors: Hiromoto
authors: H
authors: Ohta
authors: Michiyo
authors: M
authors: Kitaguchi
authors: Tadaaki
authors: T
authors: Kawakami
authors: Keiko
authors: K
authors: Iwasaki
authors: Etsuko
authors: E
authors: Tsujisawa
authors: Yoshiharu
authors: Y
authors: Morino
authors: Kazue
authors: K
authors: Tabita
mesh_terms: D000818:Animals; D004196:Disease Outbreaks; D004768:Enterotoxins / Q000032:analysis / Q000235:genetics* / Q000302:isolation & purification; D005516:Food Microbiology; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008892:Milk / Q000382:microbiology*; D016133:Polymerase Chain Reaction; D013202:Staphylococcal Food Poisoning / Q000453:epidemiology* / Q000382:microbiology*; D013211:Staphylococcus aureus / Q000235:genetics / Q000302:isolation & purification*
chemical_list: D004768:Enterotoxins; C026066:enterotoxin A, Staphylococcal