Which statement about confirming a case in an outbreak investigation is true?

• A. Publishing results without analysis is an essential step.
• B. Sequencing the pathogen is the only necessary step.
• C. Confirming the diagnosis is part of the process; publishing results is not a standard step.
• D. Defining a case is not necessary if cases are obvious.

Answer: (D)

The key idea is that confirming a case in an outbreak involves two essential parts: applying a clear case definition and confirming the diagnosis for each suspected case. Even when cases seem obvious, a standardized case definition ensures consistent identification across investigators and over time, so you don’t miss atypical presentations or misclassify cases. Diagnosing or lab-confirming cases as appropriate is the core of confirmation, because it verifies that the illness is actually part of the outbreak and not something else.

Publishing results is a step that occurs after you’ve analyzed and interpreted the data, and it’s not a required component of the confirmation process itself. You wouldn’t rely on publishing as part of how you confirm each case; rather, you focus on case classification and diagnostic confirmation first, then share findings as a separate activity.

For context, options that imply publishing results without analysis, or relying solely on sequencing as the only necessary step, are not aligned with how confirmation works. Defining a case is always important for standardization, even if the outbreak seems straightforward, because it guides who is counted as a case and ensures consistency across the investigation.