Question

A group of people had pastries late at night followed by bouts of vomiting early in the morning. What could be the cause?

• A. S. aureus
• B. B. cereus
• C. E. coli
• D. Lactobacillus

Hint:

Consider which organism produces a preformed heat-stable enterotoxin in cream-based foods causing rapid-onset vomiting.

Answer 1

The Correct Option is A

Step 1: Analyse the epidemiological clues. A group of people consumed pastries (a cream/dairy-containing food) late at night and developed vomiting early the next morning. The short incubation period (6-8 hours) and the predominant symptom of vomiting point toward a preformed toxin rather than invasion.

Step 2: Identify the organism that produces a preformed heat-stable toxin in cream-based foods. Staphylococcus aureus produces enterotoxins (heat-stable, preformed) in high-sugar, high-protein foods like cream pastries, custards, and sandwiches. The incubation period is typically 1-6 hours, with abrupt onset of nausea and vomiting as the dominant symptoms.

Step 3: Compare with other options.

• Bacillus cereus has two syndromes: emetic form (rice, 1-6 hrs) and diarrheal form (8-16 hrs); while it can cause vomiting, the food vehicle here is pastries not fried rice.
• E. coli (especially ETEC) causes watery diarrhea, not primarily vomiting, with a longer incubation.
• Lactobacillus is a probiotic and not a foodborne pathogen.

Conclusion: The short incubation, group outbreak, vomiting predominance, and cream pastry vehicle are classic for S. aureus food poisoning.