Which of the following explains why contagious infections are becoming a central focus of public health? (Select all that apply.)

Correct Answer: B

Rationale: Step 1: Awareness of human susceptibility to animal diseases has been publicized, leading to increased concern about zoonotic infections. Step 2: Zoonotic infections can easily spread from animals to humans, causing contagious outbreaks. Step 3: Public health efforts are focusing on preventing and controlling these infections to protect human health. Summary: A: Fear of bioterrorism is not a primary reason for the focus on contagious infections. C: No information is provided to support this choice. D: Drug-resistant strains of old diseases are a concern, but not the main reason for the current focus on contagious infections.

Correct Answer: A

Rationale: The hallmark feature of an analytic study in epidemiology is the use of an appropriate comparison group (Choice A). This is crucial for determining the relationship between an exposure and an outcome. By comparing individuals with the exposure to those without, researchers can evaluate the association. Randomization (Choice B) is a feature of experimental studies, not analytic epidemiological studies. Confirmation of diagnosis via lab testing (Choice C) is important for accuracy but not specific to analytic studies. Testing a hypothesis (Choice D) is a general research concept and not unique to analytic epidemiological studies.

Correct Answer: C

Rationale: The correct answer is C: Prevalence rate. In this case, the nurse is studying the proportion of the population that had pneumonia during the winter months. Prevalence rate measures the total number of existing cases in the population at a specific point in time, which aligns with the nurse's objective to study the proportion of the population affected by pneumonia during the winter months. Incorrect choices: A: Attack rate measures the proportion of people exposed to a particular factor who develop the disease. B: Incidence rate measures the number of new cases of a disease that develop in a population over a specific period. D: Risk ratio compares the risk of developing a disease in the exposed group to the risk in the non-exposed group. In summary, prevalence rate is the appropriate measure as it focuses on the total number of existing cases of pneumonia in the population, while the other choices do not match the nurse's objective in this scenario.

Correct Answer: B

Rationale: The correct answer is B: Environment. The epidemiological triad consists of three components - host, agent, and environment. The environment plays a crucial role in determining the interactions between the host and agent, influencing the occurrence and spread of diseases. Susceptibility (A) refers to the host's vulnerability to a disease, portal of exit (C) is the route through which an infectious agent leaves the host, and pathogenicity (D) is the ability of an agent to cause disease. These factors are important in disease transmission but are not part of the epidemiological triad itself.

Correct Answer: C

Rationale: The correct answer is C: Lyme disease. The "bull's eye" rash is a classic symptom of Lyme disease, caused by the bacterium Borrelia burgdorferi. This rash appears as a red circular rash with a clear center, resembling a bull's eye. This distinctive rash is a result of the bacteria spreading in the skin. Other choices are incorrect as they do not present with a bull's eye rash. Zika virus presents with fever and rash, West Nile virus with fever and neurological symptoms, and Dengue fever with fever, severe headache, and joint pain. Lyme disease is the only condition among the options that specifically presents with a bull's eye rash.