Forecasting Engine for Epidemic Response Planning

Regulatory Framework

The epidemic-response regulatory landscape has converged on a small set of operational obligations that any planning system must satisfy. IHR 2005 Articles 5 through 13 require State Parties to maintain core surveillance and response capacities, to assess events using the Annex 2 decision instrument, and to communicate risk assessments to the WHO within 24 hours of a Public Health Emergency of International Concern (PHEIC) determination. The instrument explicitly requires that assessment account for uncertainty and for plausible alternative scenarios rather than a single trajectory.

Domestically, the PHEMCE strategy and implementation plan require integrated planning across HHS, the Department of Defense, the Department of Veterans Affairs, and the Department of Homeland Security for medical countermeasure development, stockpiling, and deployment. The CDC ELC cooperative agreement obligates state, local, tribal, and territorial recipients to maintain detection, laboratory, and epidemiology capacity that produces evidence streams for federal aggregation. BARDA's Project BioShield authorities tie advanced development funding to defined epidemiological triggers, and the FDA's EUA pathway under section 564 of the Federal Food, Drug, and Cosmetic Act conditions authorization on a documented record of risk-benefit analysis at the time of issuance.

The HHS National Health Security Strategy and its quadrennial implementation plans add a longitudinal dimension: jurisdictions must demonstrate capability over time, not only during incidents. The 2025 Pandemic Preparedness Executive Order extends this expectation, directing agencies to maintain rolling readiness assessments and to coordinate scenario libraries across the federal interagency. In Europe, the CBRN-E action plan and ECDC's epidemic intelligence framework codify analogous obligations, with the EU's Health Emergency Preparedness and Response Authority (HERA) operating an explicit scenario portfolio that conditions procurement and deployment decisions. The NIH Bioethics and Pandemic Preparedness program adds a parallel track of ethical review for the resource-allocation and triage decisions that inevitably arise when interventions must be promoted or withheld under uncertainty.

Across all of these frameworks, three structural demands recur: scenario plurality, evidence-gated action, and an auditable decision record. A planning system that cannot represent these natively will satisfy them only through after-the-fact narrative reconstruction, which is precisely what post-incident reviews repeatedly find inadequate.

Architectural Requirement

Translating the regulatory lattice into architectural terms produces a small set of non-negotiable capabilities. First, the planning substrate must hold multiple transmission scenarios concurrently, each with its own parameter assumptions, intervention plan, resource commitments, and communication posture. The IHR Annex 2 instrument, the ECDC rapid risk assessment methodology, and the HERA scenario portfolio all assume that planners reason over a portfolio rather than a point estimate.

Second, each scenario must carry its own evidentiary state and its own promotion criteria. EUA decisions, BARDA acquisition triggers, and IHR PHEIC determinations all reference defined thresholds. The architecture must record which evidence has been observed, which thresholds have been crossed, and which have not, in a form that survives staff turnover and political transition.

Third, interventions must be representable as planned but uncommitted until promotion criteria are satisfied. Enhanced surveillance, targeted quarantine, school closure, travel restriction, mass vaccination, and stockpile release each have distinct evidence requirements and distinct social and economic costs. The architecture must distinguish between an intervention that is prepared and an intervention that is deployed, and must prevent premature commitment when political pressure outruns evidence.

Fourth, the planning state must aggregate across jurisdictions. Epidemics traverse county, state, and national boundaries; CDC ELC recipients, EU Member States, and WHO State Parties must coordinate without surrendering their own decision authority. The architecture must support local autonomy with federated visibility into adjacent planning postures.

Fifth, every promotion, demotion, and threshold evaluation must be recorded structurally rather than narratively. NHSS reviews, congressional oversight, parliamentary inquiry, and post-incident WHO After Action Reviews all demand a record that shows what was known, what was decided, and why. Architectures that produce decisions without producing the record force reviewers to reconstruct intent from email threads and meeting minutes, which is the failure mode every recent pandemic review has criticized.

Why Procedural Compliance Fails

The dominant approach to epidemic-response planning relies on procedural compliance: standing operating procedures, exercise programs, and after-action review templates layered over forecasting tools that produce single-trajectory projections. This approach fails the regulatory framework in several specific ways.

Single-trajectory forecasts cannot represent scenario plurality. When the planning artifact is one curve, the planner who wishes to consider an alternative must build a second artifact, manage its consistency with the first, and reconcile the two when data arrives. In practice, alternatives are sketched in side documents that diverge from the operational plan within days. The IHR Annex 2 expectation that decisions account for plausible alternatives becomes a documentation exercise rather than an operational reality.

Procedural promotion criteria recorded in policy documents fail under pressure. A school-closure threshold described in a tabletop exercise has no force when a governor demands closure before evidence accumulates or refuses closure after evidence is overwhelming. Without structural gating, the criteria become advisory, and the decision record reduces to the meeting at which the decision was announced. EUA reviewers and congressional oversight committees consistently find this insufficient.

Multi-jurisdiction coordination through procedural channels produces inconsistent postures. State A's targeted quarantine collides with State B's open-border posture; ECDC guidance diverges from individual Member State action. Procedural coordination depends on calls, memos, and bilateral agreements that cannot keep pace with epidemic dynamics. The result is the oscillation between under- and over-response that the NHSS, the EU CBRN-E plan, and the WHO IHR review committees have repeatedly identified.

Finally, procedural recordkeeping produces narrative artifacts that cannot be machine-validated. Auditors examining a procedural compliance posture must read documents, interview staff, and infer intent. The pandemic preparedness executive order, the NHSS implementation plan, and ECDC's audit framework increasingly demand structured records that can be queried, aggregated, and compared. Procedural compliance does not produce them.

What AQ Primitive Provides

The Adaptive Query forecasting engine represents each transmission scenario as a planning branch in a governed planning graph. A branch carries its parameter assumptions, its intervention plan, its resource commitments, its communication posture, and its evidentiary state. The mild branch plans for enhanced surveillance and voluntary measures; the moderate branch plans for targeted quarantine, surge capacity, and selective closures; the severe branch plans for broad community measures, emergency healthcare expansion, and continuity of essential services. All three branches exist concurrently from the outset of the incident.

Each branch carries promotion criteria expressed structurally: which case-count thresholds, hospitalization rates, transmission ratios, severity distributions, or laboratory findings must be observed before a planned intervention is promoted from prepared to deployed. As epidemiological data arrives through the CDC ELC pipeline, ECDC epidemic intelligence, or WHO event-based surveillance, the planning agent updates the evidentiary weight on each branch and evaluates each pending promotion. Interventions common to all scenarios, such as enhanced surveillance, promote early. Interventions specific to severe scenarios remain contained until the evidence threshold is crossed.

The containment boundary is the structural feature that prevents premature commitment. A planning agent under political pressure can demonstrate through the planning graph that the evidence does not yet support a severe-scenario intervention while showing that preparations for that intervention are being maintained. The boundary is bidirectional: it also prevents under-response, because evidence crossings trigger promotion automatically and produce a structural record of the crossing.

The executive graph aggregates planning across jurisdictional agents. A federal agent can observe the planning postures of state agents, identify coordination opportunities and conflicts, and route findings without overriding local authority. When one jurisdiction's travel restriction interacts with another's containment plan, the aggregation surfaces the interaction rather than relying on a phone call to discover it. ECDC and HERA can operate analogous federation across Member States.

Every promotion, demotion, threshold evaluation, and aggregation event is recorded in the planning graph as a structural artifact. The record shows the criteria as defined, the evidence as observed, the timing of each event, and the cognitive state of the planning agent at the time. After-action reviewers can query the record directly. EUA submissions, BARDA acquisition justifications, and IHR notifications can be generated from the same structural source rather than reconstructed from narrative.

Compliance Mapping

IHR 2005 Article 6 notification and Annex 2 assessment map directly onto the planning graph. The Annex 2 decision instrument's serious, unusual, international-spread, and travel-or-trade-restriction questions are scenario-portfolio queries that the forecasting engine answers from current branch state. Article 5 surveillance core capacity is satisfied by the evidentiary pipelines that feed branch updates.

CDC ELC reporting obligations are satisfied through the structural record. Recipients can demonstrate detection, laboratory, and epidemiology capacity by exhibiting the evidence streams flowing into branch updates and the decision artifacts produced from them. PHEMCE integrated planning is supported by the executive graph's cross-agency aggregation.

BARDA acquisition triggers and FDA EUA risk-benefit records are produced from branch promotion events. The promotion record shows which evidence was observed, which threshold was crossed, and what intervention or countermeasure was deployed in response. EUA section 564 documentation is generated from the same record rather than separately authored.

HHS NHSS quadrennial review obligations are supported by the longitudinal planning graph, which retains scenario history, intervention history, and aggregation events across reporting cycles. The 2025 Pandemic Preparedness Executive Order's rolling readiness assessment is produced as a query over the same structure.

EU CBRN-E action plan obligations and ECDC rapid risk assessment methodology map onto the same scenario portfolio, with HERA's procurement decisions tied to branch promotion events. NIH Bioethics review of allocation and triage decisions is supported by the structural record of which interventions were considered, which were promoted, and which were withheld, with the evidentiary basis for each.

Adoption Pathway

Adoption proceeds in stages aligned with regulatory cycles. Initial deployment instantiates the planning graph for a single jurisdiction or program office, importing existing scenario libraries and intervention catalogs. The first cycle produces a structural record of an exercise or a real incident, which is presented in the next NHSS, ECDC, or IHR review.

Subsequent cycles federate the executive graph across jurisdictions, beginning with bilateral pairs that already coordinate operationally and expanding to regional and national aggregation. The federation preserves local authority while producing the cross-jurisdictional visibility that the CBRN-E action plan, the NHSS, and the IHR State Party review process expect.

Mature deployment integrates the planning graph with the EUA, BARDA, and HERA procurement pipelines so that promotion events flow directly into countermeasure deployment and stockpile release. The structural record becomes the primary artifact of regulatory compliance, with narrative documentation generated from it rather than authored alongside it. At that point, the forecasting engine has delivered what the regulatory lattice has always presupposed but never been able to require: a planning substrate that holds plurality, gates promotion on evidence, federates across jurisdictions, and produces an auditable record as a structural property rather than an after-the-fact reconstruction.