MCCQE Part 1 MCQs by Subject: Infectious Disease, Population Health & Pathology

Sample MCCQE Part 1 MCQs from Infectious Disease, Population Health and Pathology — the last three subjects in HighYield's MCCQE bank without a dedicated post, each with the correct answer explained.

Infectious Disease, Population Health and Pathology are the last three named subject categories in HighYield's MCCQE Part 1 question bank without a dedicated practice post — Medicine, Pediatrics, Psychiatry, Surgery, PMCH and Obstetrics & Gynecology all already have one. Below are sample vignette-style MCQs grouped by theme, with the correct answer marked and a short explanation.

Infectious Disease

1. A patient develops fever, headache and a petechial rash after a camping trip with tick exposure in an endemic area. Empiric doxycycline is started for suspected:
A) Lyme disease B) Rocky Mountain spotted fever ✅ C) Malaria D) Babesiosis
Explanation: RMSF classically presents with fever, headache and a petechial/maculopapular rash after tick exposure; empiric doxycycline shouldn't be delayed waiting for serology.

2. Which of the following is a live attenuated vaccine, and therefore generally contraindicated in pregnancy?
A) Inactivated influenza vaccine B) MMR (measles-mumps-rubella) ✅ C) Tdap D) Hepatitis B vaccine
Explanation: MMR is live attenuated; live vaccines are generally avoided in pregnancy due to theoretical fetal risk.

Population Health

3. A screening program appears to extend survival simply because disease is detected earlier in its course, without actually changing the outcome. This is:
A) Length-time bias B) Lead-time bias ✅ C) Selection bias D) Recall bias
Explanation: Lead-time bias occurs when earlier diagnosis makes survival look longer, even though the disease's actual course is unchanged.

4. A healthcare system in which government both finances and directly delivers care, through publicly owned hospitals and salaried physicians (e.g., the UK's NHS), is best described as the:
A) Bismarck model B) Beveridge model ✅ C) Out-of-pocket model D) Social health insurance model
Explanation: The Beveridge model is government-funded and government-delivered, distinct from social-insurance (Bismarck) or single-payer-insurance models.

Pathology

5. Psammoma bodies on histology are most classically associated with which tumour?
A) Follicular thyroid carcinoma B) Papillary thyroid carcinoma ✅ C) Medullary thyroid carcinoma D) Anaplastic thyroid carcinoma
Explanation: Psammoma bodies are a hallmark finding in papillary thyroid carcinoma (also seen in serous ovarian tumours and meningioma).

6. Compared with necrosis, apoptosis is characterised histologically by:
A) Cell swelling and membrane rupture B) Cell shrinkage with chromatin condensation and an intact membrane ✅ C) A dense inflammatory infiltrate D) Coagulative change in the cytoplasm
Explanation: Apoptosis is a regulated, non-inflammatory process marked by cell shrinkage and chromatin condensation, unlike the membrane rupture and inflammation seen in necrosis.

Keep Practicing

For the full set of MCCQE Part 1 Infectious Disease, Population Health and Pathology questions, see HighYield's complete MCCQE Part 1 question bank, or read our MCCQE Part 1 complete guide for the bigger picture.