Epidemiology: carrier states: practice question

A PSM 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.

Try it

PSM · Epidemiology: carrier states

Sample item

A 35-year-old cook who had typhoid fever 14 months ago has no symptoms, but repeated stool cultures grow Salmonella Typhi, and ultrasound shows gallstones. How is he best classified?

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

The answer and the reasoning

D. Chronic carrier

A chronic carrier continues to excrete the organism for a prolonged period, conventionally beyond one year, after the clinical illness. In typhoid the organism persists in the gallbladder, often with gallstones, and food handlers who are carriers are an important source of outbreaks. Carriers are traced by cultures and managed with treatment, and cholecystectomy is considered in some cases.

Option by option

  • A. Incubatory carrier

    An incubatory carrier sheds the organism during the incubation period, before symptoms appear.

  • B. Healthy contact carrier

    A healthy contact carrier has never had the disease but harbours the organism after exposure to a case.

  • C. Convalescent carrier

    A convalescent carrier sheds the organism for a shorter period after recovery, within a few months.

  • D. Chronic carrier (correct)

    Correct. Excretion for more than a year after illness, with gallbladder harbouring, defines a chronic carrier.

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.

More PSM questions

Questions about this PSM question

What is the answer to this PSM question?

The best answer is D, Chronic carrier. A chronic carrier continues to excrete the organism for a prolonged period, conventionally beyond one year, after the clinical illness.

Why is "Incubatory carrier" not the answer?

An incubatory carrier sheds the organism during the incubation period, before symptoms appear.

Why is "Healthy contact carrier" not the answer?

A healthy contact carrier has never had the disease but harbours the organism after exposure to a case.

Why is "Convalescent carrier" not the answer?

A convalescent carrier sheds the organism for a shorter period after recovery, within a few months.

What concept does this question test?

It tests Epidemiology: carrier states in PSM. In typhoid the organism persists in the gallbladder, often with gallstones, and food handlers who are carriers are an important source of outbreaks. Carriers are traced by cultures and managed with treatment, and cholecystectomy is considered in some cases.

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 Epidemiology: carrier states?

Practise biostatistics with small calculations until sensitivity, predictive values and risk measures are automatic. Then use the flashcards and the other PSM 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.