Epidemiology & Prevention USMLE Step 1 Practice Question
A new antiviral medication is introduced for a chronic infection in a city of 1 million people. The drug does not prevent new infections, but it markedly shortens the duration of symptomatic illness and improves recovery. One year later, epidemiologists compare disease frequency with the year before the drug was introduced. Which of the following changes is most likely?
Answer choices
- ADecreased incidence and unchanged prevalence
- BUnchanged incidence and unchanged prevalence
- CIncreased incidence and increased prevalence
- DUnchanged incidence and decreased prevalenceCorrect answer
- EDecreased incidence and decreased prevalence
- FIncidence increases as more patients survive longer
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