I stay with this Challenge.
Challenge / Chloé / ML2 SEIR
Interrupt the hidden SEIR lead wave before it becomes visible as I.
coach_text Model view Start parameters, registry and assumptions
SEIR / Challenge
Interrupt the hidden SEIR lead wave before it becomes visible as I.
You are working for the Everytown Health Department. In Everytown, with around 350,000 residents, a wave is building that is already further along in E than on the visible I-curve.
The reference curve shows the outbreak without your Challenge decisions. Your mission curve changes only through the interventions you select.
The important comparison is not only the visible peak. The review also reads timing, total infections, pressure and the model state at the result horizon.
Read the outbreak trace
At the start this panel is locked to day 0. Later it opens at the current simulation day and lets you review only the observed past.
Day 0
observed up to day 0
No intervention active.
Rₑff will appear here.
Important distinction
R₀ is fixed as the reference. The open levers act on effective pathways such as beta_eff, vaccination_rate or E isolation.
What can change, what stays fixed?
The registry separates fixed model references from actual intervention pathways.
fixed
R₀ as fixed reference
The basic reproduction value describes the outbreak without intervention. It stays fixed as the reference in Challenge.
R₀ = β / γ
Interventions do not change R₀ itself; they change effective pathways such as β_eff, γ_eff or isolation.
can be changed
Effective transmission
Contact and protection measures lower effective transmission and therefore indirectly lower Rₑff.
β_eff = β * (1 - mitigation_eff / 100)
Contact and protection measures lower effective transmission and therefore indirectly lower Rₑff.
fixed
Capacity threshold
Evaluation and event target: the threshold controls warning, escalation and review.
threshold = mission.targets.peakMax
Evaluation and event target: the threshold controls warning, escalation and review.
fixed
Visibility and early warning
Not a direct curve lever, but a later explanation layer for monitoring, testing and triggers.
visibility = observed(model_state, trigger_metric)
Not a direct curve lever, but a later explanation layer for monitoring, testing and triggers.
can be changed
E isolation
SEIR-specific lever: part of the hidden lead wave is filtered before later onward contacts.
isolated_new = sigma * E * isolation_eff
SEIR-specific lever: part of the hidden lead wave is filtered before later onward contacts.
Intervention set
Duration, pressure, effect path and formula.
Path Acts on β_eff and E isolation: effective contacts drop, and part of the hidden E pathway is filtered before it feeds later I.
Formula
βeff=β⋅(1−100meff)
meff=mbaseline+3PP(21days)
Eiso→I=qiso⋅σ⋅E
qiso=qbaseline+8%(21days)
Model assumption In the Challenge dummy, the hygiene campaign changes β_eff and a share of E isolation for the duration of the intervention.
Path Acts on β_eff and E isolation: effective contacts drop, and part of the hidden E pathway is filtered before it feeds later I.
Formula
βeff=β⋅(1−100meff)
meff=mbaseline+11PP(21days)
Eiso→I=qiso⋅σ⋅E
qiso=qbaseline+58%(21days)
Model assumption In the Challenge dummy, E-group isolation represents early isolation of contacts before they themselves become visibly infectious.
Path Acts on β_eff and E isolation: effective contacts drop, and part of the hidden E pathway is filtered before it feeds later I.
Formula
βeff=β⋅(1−100meff)
meff=mbaseline+14PP(21days)
Eiso→I=qiso⋅σ⋅E
qiso=qbaseline+42%(21days)
Model assumption Shielding does not act directly on symptoms in the model, but on later contact opportunities from the hidden lead wave.
Path Acts on β_eff and E isolation: effective contacts drop, and part of the hidden E pathway is filtered before it feeds later I.
Formula
βeff=β⋅(1−100meff)
meff=mbaseline+24PP(14days)
Eiso→I=qiso⋅σ⋅E
qiso=qbaseline+80%(14days)
Model assumption Expanded isolation is modelled as a temporary change in β_eff and E isolation.
Path Acts on β_eff and E isolation: effective contacts drop, and part of the hidden E pathway is filtered before it feeds later I.
Formula
βeff=β⋅(1−100meff)
meff=mbaseline+16PP(21days)
Eiso→I=qiso⋅σ⋅E
qiso=qbaseline+70%(21days)
Model assumption In the dummy model, entry checks stand for broad testing and access rules. They change β_eff and the filter pathway from E to I.
The end of the run is derived from your curve
The scenario has a minimum horizon, but the actual result horizon can move when interventions delay the wave.
The minimum horizon starts at 72 days. The runtime keeps a technical buffer up to about 972 days, so delayed waves can still settle.
After each decision, the live curve is simulated again. The result horizon is then derived from that live curve: the run ends only once the relevant compartments have settled enough for review.
This is why a successful delay may also make the run longer. Reference and mission are compared at the same result horizon.
ChloéENguidedguided
Chloé / Situation brief
The health department now has to read the hidden lead wave.
Everytown has around 350,000 residents. Reports of a new respiratory virus are increasing, but part of the spread has not yet arrived as a visible wave of illness.
Your task: read the E lead wave early enough so that later infectious cases generate as few new contacts as possible. A response that is too soft can buy time, but often forces harder interventions later.
Play the threshold directive automatically when the crisis window opens?
Ready
Day 0 / 72Start the mission and respond when a window opens.
Currently infectious
0
Currently exposed
0
Until threshold
0
Before each decision, the visible I situation and the hidden E lead wave can be read together here.
Your result
At the end, what matters is how strongly you influenced the later I-wave through the advantage of the yellow E lead wave, whether early measures kept the situation under control and whether later escalation was really necessary.
0
At the end you see what your plan changed.
Score
0 / 100
Without measures
0
Peak 0
With your plan
0
Peak 0
S Susceptible
0.0 %
E Exposed
0.0 %
I Infectious
0.0 %
R Recovered
0.0 %
Situation before you decide
This shows how many people are affected right now, not just abstract percentages.
Currently sick
0
Sick so far
0
Recovered
0
Residents
0
Available now
Interventions
After Supervision
Harder interventions
These interventions unlock only after the capacity threshold.
- Screening & access Entry checks
- Containment management Expand isolation
Department directive · Asher
Critical threshold exceeded
Show transcript
The latest figures confirm that the outbreak has exceeded the critical threshold. This requires an immediate and effective response from the Department of Health and all relevant agencies. I am asking you to act swiftly, implement measures with clear impact, and ensure that public health remains our highest priority.
Supervision
Supervision due to hidden lead wave
As long as the combined pressure from exposed and infectious people stays below 7.0%, later interventions remain locked. If this hidden lead wave tips, leadership requests supervision.
Department directive · Asher
Critical threshold exceeded
Show transcript
The latest figures confirm that the outbreak has exceeded the critical threshold. This requires an immediate and effective response from the Department of Health and all relevant agencies. I am asking you to act swiftly, implement measures with clear impact, and ensure that public health remains our highest priority.
Mission status
Mission ready
Success is not about maximum force, but about balancing effect and proportionality.
Your result
At the end, what matters is how strongly you influenced the later I-wave through the advantage of the yellow E lead wave, whether early measures kept the situation under control and whether later escalation was really necessary.
0
At the end you see what your plan changed.
Score
0 / 100
Without measures
0
Peak 0
With your plan
0
Peak 0
Decisions
What you have chosen so far
- No decision yet.
Early E window
Pre-peak window
Correction window
Crisis window
Day 0Day 72