Which of the following is an epidemiologic function of the nurse during an epidemic?

Correct Answer: C

Rationale: The correct answer is C because participating in the investigation to determine the source of the epidemic is a key epidemiologic function of the nurse during an epidemic. This involves identifying the origin of the outbreak to implement targeted control measures and prevent further spread. A is incorrect because while conducting assessments is important, it is not a specific epidemiologic function related to determining the source of an epidemic. B is incorrect as monitoring cases focuses on individual care rather than epidemiologic investigation. D is incorrect as educating the community, while important, is not directly related to determining the source of the epidemic.

Correct Answer: D

Rationale: The correct answer is D because person-to-person propagated epidemics typically exhibit a gradual build-up of cases before becoming easily noticeable. This is due to the slow transmission of the disease from one individual to another. In contrast, choice A is incorrect because having more cases than expected is not a characteristic unique to person-to-person propagation. Choice B is incorrect as person-to-person transmission does not necessarily involve a vector. Choice C is incorrect because common vehicle spread refers to a different mode of disease transmission.

Correct Answer: A

Rationale: The correct answer is A: Establishing the epidemic. During this stage, comparing the present disease frequency with the usual frequency helps determine if there is a significant increase, indicating an epidemic. This step is crucial for recognizing and confirming the outbreak. Testing the hypothesis (B) comes after the epidemic is established. Formulation of the hypothesis (C) involves developing a theory based on observations, not comparing frequencies. Appraisal of facts (D) occurs after data collection, not during the initial comparison.

Correct Answer: B

Rationale: Step 1: Cyclical variation refers to a pattern that repeats at regular intervals. Step 2: The increase in Dengue fever cases at the end of the rainy season is a recurring pattern. Step 3: The rise in cases is linked to the environmental conditions during the rainy season. Step 4: This cyclic increase in cases is not a sudden outbreak (epidemic) or random (sporadic). Step 5: Secular occurrence refers to long-term trends, not short-term patterns like the end of a season. Summary: Choice B is correct because the pattern of Dengue fever cases increasing at the end of the rainy season aligns with cyclical variation, unlike the other options which do not accurately describe this specific pattern.