INTRODUCTION:
The diversity and increasing frequency of events involving infectious disease and other hazards affecting public health are potent reminders that the International Health Regulations (2005)1,2, an efforts to build surveillance systems remain foundational criteria to global health security3. The incident timeliness metrics have been integrated into the WHO after-action review process and the Triple Billion targets for its 13th General Programme of Work (GPW13)4,5. Evaluation of outbreak timeliness and response capacity of Lassa fever three years post outbreak after action review report to assess the preparedness improvement performance and the outbreak response capacity in Ondo State

METHODS:
We conducted an evaluation timeliness of the after action review report of Lassa fever between January, 2023 to September, 2025 using the 7-1-7 accountability framework with three timeliness metric targets for outbreak detection, notification and response as a verifiable bench mark6,7

RESULTS:
Of the 1024 Lassa fever confirmed outbreak only 49% cases met the overall 7-1-7 target. The timeliness of the outbreak start to outbreak discovery increases slightly from a mean of 6.9 days to 7.1 days. There was a median of 6 days (IQR 0–17) for time to detection and 1 day (IQR 0–3) for time to notification.

CONCLUSIONS:
The timeliness of detection during the study period improved substantially, indicating advances in surveillance systems. Preparedness towards emergencies is a process and always require continuous concerted effort. Lassa fever preparedness was confronted by competing prioritizes. However, the response was evaluated as effective and sufficiently prompt with an increase coordinated collective effort of the stakeholders.