Bacteriology: staphylococcal food poisoning: practice question

A Microbiology question in the style of the NEET PG paper. Answer it first, then read why the right option is right and why each of the others is wrong.

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Microbiology · Bacteriology: staphylococcal food poisoning

Sample item

Four guests develop severe vomiting 3 hours after eating a custard dessert that was left unrefrigerated and then reheated before serving. Fever is absent and they recover in a day. Why did reheating fail to make the food safe?

AThe enterotoxin is preformed and heat stableBStaphylococcal spores survive boilingCThe toxin is produced inside the gut after ingestionDReheating selects toxin-resistant bacteria

Original practice item, not a recalled exam question. Nothing here is recorded.

The answer and the reasoning

A. The enterotoxin is preformed and heat stable

Staphylococcus aureus multiplies in contaminated food and releases enterotoxin, which is a heat-stable, preformed superantigen resistant to boiling for 30 minutes. Short incubation of 1 to 6 hours with vomiting and no fever is typical. Treatment is supportive, and prevention requires hygiene and refrigeration.

Option by option

A. The enterotoxin is preformed and heat stable (correct)
Correct. Cooking kills the bacteria but not the preformed toxin.
B. Staphylococcal spores survive boiling
Staphylococci do not form spores; the toxin is the problem.
C. The toxin is produced inside the gut after ingestion
The toxin acts after ingestion but is already formed in the food.
D. Reheating selects toxin-resistant bacteria
Reheating does not select resistance; the toxin simply survives.

Source note: Original NextPrep sample item — pending expert review. This item is original practice material awaiting independent expert review, so confirm important facts in a standard textbook.

Questions about this Microbiology question

What is the answer to this Microbiology question?

The best answer is A, The enterotoxin is preformed and heat stable. Staphylococcus aureus multiplies in contaminated food and releases enterotoxin, which is a heat-stable, preformed superantigen resistant to boiling for 30 minutes.

Why is "Staphylococcal spores survive boiling" not the answer?

Staphylococci do not form spores; the toxin is the problem.

Why is "The toxin is produced inside the gut after ingestion" not the answer?

The toxin acts after ingestion but is already formed in the food.

Why is "Reheating selects toxin-resistant bacteria" not the answer?

Reheating does not select resistance; the toxin simply survives.

What concept does this question test?

It tests Bacteriology: staphylococcal food poisoning in Microbiology. Short incubation of 1 to 6 hours with vomiting and no fever is typical. Treatment is supportive, and prevention requires hygiene and refrigeration.

How hard is this question?

We tag it as an application question: it asks you to use a fact on a patient or a finding. The tag is our own editorial judgement, not an official difficulty rating, so read the reason for every option, not only the answer.

How should I study Bacteriology: staphylococcal food poisoning?

Make a one-line identity card for each organism: shape and stain, defining test, toxin, disease and drug. Then use the flashcards and the other Microbiology questions on this site to test what stuck.

Is this a real NEET PG question?

No. It is an original practice item (editorial status: sample, version 1). NextPrep does not publish recalled or leaked questions, and independent faculty review of this item has not been completed yet, so confirm important facts in a standard textbook.