← Back to scans

Will there be a year with zero wild polio cases before 2030?

KXPOLIOELIM-30 · Health · 2026-04-29
4%
Agent
4%
Market Price
-0.3%
Edge
72%
Confidence
Volume: 28,331
Spread: 5.7c
Days to resolution: 1342
Markets in event: 1
Final Rationale
WPV1 has never recorded a zero-case calendar year in surveillance history, and 2024-2026 are effectively ruled out by confirmed ongoing circulation (CDC March 2026 travel notice, ~70 Pakistan cases in 2024). I partially accept the critic's point that ensemble spread of zero suggests insufficient genuine contrarianism and that surveillance gaps in conflict zones could theoretically produce an artifactual zero year, but these considerations are already roughly priced into the low-but-nonzero 4% estimate — going from dozens of cases to literal zero in 2027-2029 requires a near-miraculous trajectory. I reject the suggestion to widen uncertainty meaningfully because the structural barriers (Pakistan/Afghanistan endemic transmission, conflict disrupting vaccination, funding pressures) are well-documented. My estimate converges with the thin market at 4.3%, and given the negligible divergence I see no reason to adjust.
Price vs. prediction
How the market moved after the agent's call. Solid blue line is the actual market price; dashed line is the agent's static forecast at $t{=}0$.
$n = 58$ follow-ups
Re-scan Context
This market has been scanned before. Previous predictions:
DatePredictedMarket PriceConfidence
2026-04-03 4% 3% 50%
1. Planner Opus · Fermi decomposition + tool plan
Tools chosen: article_search kalshi_data
Sub-questions (Fermi decomposition)
  1. Will there be a year with zero wild polio cases before 2030? (w=1.00)
Planner reasoning
Fallback: general forecasting approach
2. Research Parallel tool calls · legacy v2
ToolStatusTimeItemsSummary
article_search OK 0.2s -
kalshi_data OK 0.2s -
3. Evidence Synthesis Sonnet · 5 items · legacy v2
#StrengthCredibilityDirectionSourceClaimPriced In
1 MODERATE 62 ↓ DOWN kalshi_data The Kalshi prediction market prices the probability of zero wild polio cases before 2030 at 4.30%, down 2.70% over 7 days and down 0.70% over 30 days. Yes
2 STRONG 85 ↓ DOWN article_search The CDC issued a Level 2 travel notice in March 2026 warning that poliovirus (including wild poliovirus) continues to circulate in multiple parts of the world, covering 30 destinations where poliovirus was found in the past 13 months. Yes
3 STRONG 82 ↓ DOWN article_search Wild poliovirus remains active globally as of early 2026, with the CDC updating travel advisories to reflect ongoing circulation and environmental detection in wastewater samples across 30 countries. Yes
4 MODERATE 70 ↓ DOWN article_search Polio, meningitis, and measles outbreaks are prompting public health concern as of April 2026, suggesting poliovirus (including wild strains) continues to pose an active global threat rather than being on the verge of elimination. Yes
5 MODERATE 75 NEUTRAL article_search Historical context: wild poliovirus has been eliminated in the US since 1979, demonstrating elimination is achievable but has taken decades and remains incomplete globally. Yes
Information Gaps
  • No specific data on current wild poliovirus type 1 (WPV1) case counts for 2025 or 2026 from GPEI (Global Polio Eradication Initiative) or WHO surveillance reports.
  • No data on the number of countries still endemic for WPV1 (historically Pakistan and Afghanistan) and their current outbreak trajectories.
  • No information on GPEI vaccination campaign progress or funding levels, especially given potential US foreign aid cuts that could affect eradication programs.
  • No data distinguishing wild poliovirus from circulating vaccine-derived poliovirus (cVDPV), which is critical since the question specifically asks about wild cases.
  • No information on environmental surveillance data from endemic regions that might signal near-elimination.
  • No recent WHO or GPEI outbreak response reports that would indicate whether case counts are trending toward zero.
Key Uncertainties
  • Whether Pakistan and Afghanistan (the last known endemic WPV1 countries) can achieve zero transmission given ongoing conflict, access challenges, and vaccine hesitancy.
  • Impact of US government funding cuts to global health programs (USAID, CDC international programs) on polio eradication efforts in 2025-2029.
  • Whether the CDC travel alert covers wild poliovirus specifically or includes cVDPV, which would affect interpretation of ongoing circulation risk.
  • The distinction between wild poliovirus 1 cases and vaccine-derived cases is critical for resolution — the question specifies WPV1 only.
  • Whether a single year of zero cases requires sustained elimination or could represent a gap in surveillance/reporting.
Market Context
Price: 0.043 · 7d: -0.027 · 30d: -0.007
Volume: LOW — 87 contracts average daily volume is quite thin · Depth: SHALLOW
Reliability: LOW-MEDIUM — very low volume market with limited liquidity; price likely reflects informed niche participants but may not be efficiently priced given thin trading. Price range of 3-10% over the observed period shows some volatility relative to the current low probability. Downward trend over 7 days may reflect recent news of continued polio circulation.
4. Independent Forecaster Opus · No market price · legacy v2 Did NOT see market price
Independent estimate: 4% (70% confidence)
base rate
4%
70% conf
evidence driven
4%
70% conf
contrarian
4%
70% conf
Spread
0pp
Low disagreement
sq1: Will there be a year with zero wild polio cases before 2030?
4%
Base rate: WPV1 has never had a globally zero case year in the modern surveillance era. Closest was 2021 with 6 cases, but 2022-2024 saw resurgence (Pakistan/Afghanistan, plus Mozambique/Malawi importations). For 2024-2029 to have a zero year, both Pakistan and Afghanistan would need to simultaneously interrupt transmission for an entire calendar year. Pakistan reported ~70+ cases in 2024 and Afghanistan also had cases. Strong evidence: CDC March 2026 travel alert confirms ongoing circulation across 30 countries as of early 2026, meaning 2024, 2025, and 2026 (in progress) are essentially ruled out. That leaves only 2027, 2028, 2029 as possible zero years — three chances. Pakistan-Afghanistan conflict, vaccine hesitancy, and potential US aid cuts push DOWN by ~3% from any optimistic scenario. Historical near-misses (2021's 6 cases) suggest it is theoretically possible to get very low, but achieving exactly zero in a calendar year given current trajectory is unlikely. Estimate: 4%.
Show full reasoning trace
base rate: Zero WPV1 cases in a calendar year has never occurred in surveillance history. Lowest was 2021 (6 cases). Endemic transmission persists in Pakistan and Afghanistan.
evidence updates: CDC March 2026 travel notice confirms active wild poliovirus circulation across 30 destinations — strong evidence that 2024, 2025, and 2026 will not be zero years. This eliminates 3 of 6 possible years, leaving only 2027-2029.
combination method: Single sub-question, weight 100%.
final: Given confirmed ongoing WPV1 circulation in 2026, conflict in Pakistan/Afghanistan disrupting vaccination, and potential funding cuts, the probability that any of 2027/2028/2029 achieves true zero WPV1 globally is low. Estimate 4%.
ensemble: {'ensemble_count': 3, 'perspectives': {'base_rate': {'p_yes': 0.04, 'confidence': 0.7}, 'evidence_driven': {'p_yes': 0.04, 'confidence': 0.7}, 'contrarian': {'p_yes': 0.04, 'confidence': 0.7}}, 'spread': 0.0, 'individual_p_yes': {'base_rate': 0.04, 'evidence_driven': 0.04, 'contrarian': 0.04}}
5. Devil's Advocate Sonnet · legacy v2 Market price revealed
Missing Info
Challenges
  1. The forecaster correctly identifies that 2024, 2025, and 2026 are essentially ruled out, leaving 2027-2029 as candidates. However, the reasoning could be sharpened: with ~70 cases in Pakistan in 2024 and continued circulation in 2026, going from dozens of cases to literally zero in a single calendar year within 1-3 years is an extreme jump. The 2021 near-miss (6 cases) was followed by resurgence, suggesting the system is not on a smooth glide path to zero.
  2. The forecast does not distinguish carefully between 'reported zero' and 'actual zero.' Even if transmission were interrupted, WHO certification of zero typically requires 3 years of zero detection. But the question asks about a calendar year with zero cases, which is more achievable than certification. The forecaster should clarify whether this slightly raises the probability (a single fluke low-detection year is possible) or not.
  3. Information gaps are significant: no GPEI/WHO surveillance numbers for 2025-2026 are cited. If 2025 case counts dropped sharply (which the forecaster doesn't know), the trajectory could be more favorable than assumed. This argues for slightly wider uncertainty rather than a tight 4% estimate with 0.7 confidence.
  4. Ensemble shows zero spread across base_rate, evidence_driven, and contrarian perspectives — all at exactly 0.04. This suggests the 'contrarian' perspective wasn't genuinely contrarian. A real contrarian view might note that GPEI has repeatedly come close (2021), surveillance gaps in conflict zones could produce an artifactual zero year, and aggressive campaigns could succeed in a 3-year window.
Market comparison: Forecaster: 4.0%, Market: 4.3%. Divergence is negligible (-0.3%). The close alignment is reassuring but coincidental — the forecaster reasoned independently from base rates and evidence, and the market (though thin) appears to reflect similar logic. No reason to adjust.
6. Aggregator Opus · final calibrated forecast
4% (72% confidence)
WPV1 has never recorded a zero-case calendar year in surveillance history, and 2024-2026 are effectively ruled out by confirmed ongoing circulation (CDC March 2026 travel notice, ~70 Pakistan cases in 2024). I partially accept the critic's point that ensemble spread of zero suggests insufficient genuine contrarianism and that surveillance gaps in conflict zones could theoretically produce an artifactual zero year, but these considerations are already roughly priced into the low-but-nonzero 4% estimate — going from dozens of cases to literal zero in 2027-2029 requires a near-miraculous trajectory. I reject the suggestion to widen uncertainty meaningfully because the structural barriers (Pakistan/Afghanistan endemic transmission, conflict disrupting vaccination, funding pressures) are well-documented. My estimate converges with the thin market at 4.3%, and given the negligible divergence I see no reason to adjust.