• Causes of rapid-onset food poison (< 6 hours) are due to ingestion of pre-formed toxin and are most commonly caused by Staph aureus (cream-based food such as egg salad) or Bacillus cereus (reheated rice syndrome)
• Key idea: Staph aureus food poisoning (most likely in this case given egg salad and rapid-onset symptoms) can either be due to improper cooking or inadequate refrigeration, but in this case given the history of a family picnic and the food likely being left out all day, inadequate refrigeration is more likely

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