Omoleke and de Kiev’s mixed-methods evaluation found the AEFI surveillance system in Kebbi State, Nigeria, to be suboptimal. Key findings showed convergence on simplicity and timeliness, partial agreement on several other attributes, dissonance on representativeness, and concerns about completeness, timeliness, knowledge gaps, and stability. The authors cautioned that the system is not robust enough to generate convincing safety data for new vaccines.

1.)  Which single design limitation most threatens valid estimates of sensitivity and representativeness? How would you address it within six weeks?

2.) Using the CDC surveillance attributes, propose one low-cost intervention to increase sensitivity. State the expected trade-offs, and list 2–3 indicators to detect impact from the intervention.

3.) For a newly introduced vaccine, should the AEFI case definition be temporarily broadened to maximize early signal detection?

– If yes, what trigger would you use to revert to the prior definition?
– If no, why should this change not be implemented?