A disadvantage of conducting continuous surveillance is:

Correct Answer: A

Rationale: Continuous surveillance, while comprehensive, is resource-intensive and time-consuming. It does allow for comparisons over time (B), can identify outbreaks (C), and is useful for establishing baseline rates (D), making 'time-consuming' the key disadvantage.

Correct Answer: A

Rationale: In outbreak terminology, a vehicle is a non-living intermediary (e.g., contaminated food or water) that transmits pathogens, distinct from living vectors like ticks (B), reservoirs (C), or transport-related spread (D).

Correct Answer: A

Rationale: The primary goal of outbreak investigation is to identify the source and implement control measures to halt the outbreak, rather than assigning blame (B), training workers (C), or prioritizing infrastructure (D), though these may be secondary benefits.

Correct Answer: B

Rationale: A line list records detailed information (e.g., demographics, symptoms) for all patients meeting the case definition, aiding analysis, unlike tracking staff (A), movements (C), or specimens (D) alone.