This market will resolve to "Yes" if there have been the specified amount or more confirmed cases of Measles (Rubeola) in humans in the territory of the United States of America in 2026, according to the CDC case counter by October 31, 2026, 11:59 PM ET.
Current leader
97.4%
97%
3 outcomes
Will there be at least 4700 measles cases in the U.S. by October 31, 2026?
Will there be at least 4800 measles cases in the U.S. by October 31, 2026?
Will there be at least 4900 measles cases in the U.S. by October 31, 2026?
Now Gained in 24h Lost in 24hChanges are in percentage points (pp).
Latest update
PlungeMonitoring onlyThe tracked probability fell to 96.45%, down 3.0 percentage points from 99.5% in the latest observation window. No evidence-qualified public source was supplied, so this remains a monitoring note rather than a causal explanation.
Yes: 100% → 96%
-3.0 ppStory so far
Recently updatedThe tracked probability fell to 96.45%, down 3.0 percentage points from 99.5% in the latest observation window. No evidence-qualified public source was supplied, so this remains a monitoring note rather than a causal explanation.
A sourced or deterministic market update is available.
Supported by the sources below
What the evidence doesn’t settle
Nothing specific is being tracked yet.
Public sources opened for this story
No public sources are attached yet.
Odds chart
Living timeline
Observed movement
Observed probability fell from 99.5% to 96.45% (-3.05 percentage points), from 2026-10-17T18:02:12.136Z to 2026-10-17T18:15:40.192Z (UTC).
Editorial research is deferred. This update preserves the observed market change. The cause of the move is not established.
The measured move
Yes: 99.5% → 96.45%
Probability moved from 99.5% to 96.45% (-3.05 percentage points). Observations were 13 minutes 28 seconds apart: 2026-10-17 18:02:12 UTC to 2026-10-17 18:15:40 UTC.
Watch further market observations and reporting about this contract. This update has not been enrolled for editorial research.
No external sources are attached yet.
Observed movement
Observed probability rose from 82.5% to 86% (+3.5 percentage points), from 2026-10-17T17:16:13.133Z to 2026-10-17T17:30:45.685Z (UTC).
Observed movement
Observed probability fell from 45% to 40.5% (-4.5 percentage points), from 2026-10-17T13:16:27.752Z to 2026-10-17T13:32:19.243Z (UTC).
Observed movement
Observed probability rose from 74.5% to 77.5% (+3 percentage points), from 2026-10-17T13:16:27.752Z to 2026-10-17T13:32:19.243Z (UTC).
Observed movement
Observed probability rose from 35% to 44.5% (+9.5 percentage points), from 2026-10-17T12:30:17.205Z to 2026-10-17T12:47:12.689Z (UTC).
Observed movement
Observed probability rose from 71% to 74% (+3 percentage points), from 2026-10-17T12:30:17.205Z to 2026-10-17T12:47:12.689Z (UTC).
Observed movement
Observed probability fell from 37.5% to 33% (-4.5 percentage points), from 2026-10-17T09:45:29.508Z to 2026-10-17T10:00:24.264Z (UTC).
Observed movement
Observed probability fell from 47.5% to 35.5% (-12 percentage points), from 2026-10-17T09:15:58.266Z to 2026-10-17T09:30:47.126Z (UTC).
Market rules, made readable
Official descriptionRead the rules before reading the headline. Resolution wording decides the outcome, not the news.
Resolves Yes
This market will resolve to "Yes" if there have been the specified amount or more confirmed cases of Measles (Rubeola) in humans in the territory of the United States of America in 2026, according to the CDC case counter by October 31, 2026, 11:59 PM ET.
Resolves No
Otherwise, this market will resolve to "No".
The resolution source for this market will be the CDC Measles (Rubeola) counter 'Total Cases' in 2026 (see: at the resolution time. If the counter becomes unavailable, another credible source will be used. Note: Only cases reported by the CDC Measles (Rubeola) counter will qualify, regardless of reports from U.S. State agencies or other sources.
Living timeline · 12 significant updates
Will there be at least 4700 measles cases in the U.S. by October 31, 2026? — probability falls to 96.45%
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