As Evidence Evolves: Epistemic Recalibration in Sequential WHO Risk Assessments of Filovirus Outbreaks, 2022–2024
Abstract
Outbreak communication occurs when institutional authorities must convey information before all evidence is available and then update the assessment as knowledge evolves. This study examines how epistemic status and evidential grounding are maintained or recalibrated in sequential World Health Organization (WHO) Risk Assessments regarding three completed filovirus outbreaks: Sudan ebolavirus in Uganda (2022–2023), Marburg virus disease in Equatorial Guinea, and Marburg virus disease in Rwanda. The study used comparative longitudinal corpus-assisted discourse analysis of 17 WHO Risk Assessment sections from 17 DONs, totaling 4,247 cleaned tokens. Corpus-assisted identification of epistemic and evidential resources was combined with manual claim-level longitudinal tracking. The analysis yielded 85 event-specific claim units, including 53 inter-report relationships that could be traced longitudinally. The results show that epistemic positioning is realized through a combination of modal possibility, knowledge-status expressions, inferential predicates, evidential framing, institutional assessment expressions, classification, and temporal updating markers. Seventy-three percent of linked relations are carry-forward, indicating that epistemic persistence is more common than substantive change. When recalibration occurs, it is selective and claim-specific: Uganda primarily exhibits institutional risk reclassification, Equatorial Guinea maintains provisional inferences regarding undetected transmission and incomplete epidemiological knowledge, while Rwanda exhibits evidential strengthening in zoonotic source attribution. The three outbreaks also demonstrate that formal outbreak closure does not produce uniform epistemic closure; current outbreak status can be declared resolved while uncertainty persists regarding source, transmission history, or future re-emergence. The study uses epistemic recalibration as a study-specific analytical construct to capture longitudinal adjustment in epistemic status, evidential grounding, or institutional commitment. The findings demonstrate the analytical value of shifting attention from the distribution of isolated uncertainty markers to the longitudinal organization of event-specific institutional knowledge.
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References
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