The U.S. measles cases 2026 market is a ladder of ten CDC case-count thresholds running from 3,000 cases up through 12,500. The year it prices is already the worst for measles in the United States since 1991, with 2,903 confirmed cases as of August 27, 2026, past the 2,289 logged across all of 2025 and still climbing behind a Pennsylvania outbreak that produced the first U.S. measles deaths of the year. The board carries roughly $8.6M in cumulative volume across Kalshi and Polymarket, and the live board above ranks the current price on every rung. It resolves December 31, 2026.
The U.S. measles cases 2026 market is a ladder of ten CDC case-count thresholds, and the year it prices has already become the worst measles year in the United States since 1991. The CDC counted 2,903 confirmed cases as of August 27, 2026, clearing the 2,289 recorded across all of 2025 with four months still on the calendar. The rungs run from 3,000 cases up through 3,500, 4,000, 4,500, 5,000, 6,000, 7,500, 8,000, 10,000, and 12,500, and the board carries roughly $8.6M in cumulative volume across Kalshi and Polymarket. The live board above ranks the current cross-platform price on every rung.
Each rung is its own contract asking whether the confirmed national total reaches at least that many cases by year end, so the ladder reads as a probability curve rather than a race between named outcomes. Prices sit high on the low thresholds the count has all but banked and fall as the rungs climb toward totals the market treats as long shots.
The rung set has moved through the year. The 2,150 threshold that anchored the bottom of this board in June was overtaken by the running count and left the ladder, and the board's default view has since climbed from the 4,500 line to the 5,000 line, which is where the market's central estimate now sits. As of August 31, 2026 the 3,000 rung trades at 99c, the 4,000 rung at 94c on Kalshi against 95c on Polymarket, the 5,000 rung at 49c, the 6,000 rung at 36c, and the 10,000 rung in single digits.
Where both books list the same rung the two prices sit side by side, and the 4,000 level is the cleanest read on whether they agree. Several rungs, including 4,500 and 6,000, are carried by only one of the two books, so a blank on one side means there is no contract there rather than a price of zero.
The arithmetic is the starting point. From 2,903 confirmed cases, the 4,000 rung needs another 1,097 before December 31 and the 6,000 rung needs 3,097. Roughly 18 weeks remain in the year. The last three CDC updates added 101, 211, and 126 cases, an average near 146 a week, and 18 weeks at that pace lands the year around 5,500. A 5,000 rung sitting close to a coin flip is therefore pricing a real slowdown from the August run rate rather than a continuation of it.
Geography does the rest. The CDC has logged 37 new outbreaks in 2026 and 94% of confirmed cases, 2,737 of 2,903, are outbreak-associated, so the total moves in clusters rather than a steady drip. The epicenter has shifted twice this year. South Carolina's Upstate chain closed in April at 997 cases, Utah carried the spring and now sits at 518 with three straight weeks of no new cases, and Pennsylvania is the current driver at 460 cases and 83 hospitalizations, at least 181 of them in Lancaster County. Ohio is the second front at 142 cases for 2026, with 40 in Ashtabula County. A single introduction into an undervaccinated community is what lifts several rungs at once, and a quiet month flattens the top of the ladder.
The Pennsylvania chain also produced the first U.S. measles deaths of 2026. The state announced two measles-associated deaths on August 25, 2026, one of them a newborn. The CDC has held both out of the national count while it reviews whether measles caused or contributed to them, so they do not move any threshold directly. They do change the response posture around the outbreak currently adding the most cases.
Vaccination coverage sits underneath all of it. MMR coverage among U.S. kindergartners has fallen to 92.4% for the 2025-2026 school year from 95.2% in 2019-2020, leaving roughly 280,000 kindergartners unprotected and national coverage below the 95% level that sustains community immunity. Containment speed matters just as much. How fast contact tracing and isolation reach a cluster decides whether it stays a dozen cases or compounds into the hundreds that South Carolina, Utah, and now Pennsylvania have each produced.
One policy catalyst hangs over the fall. The Pan American Health Organization's regional verification commission reviews U.S. measles elimination status in November 2026, with genetic evidence of sustained domestic transmission tracing back to the January 2025 West Texas outbreak. That review does not resolve this market, but it concentrates attention and response resources on exactly the chains the ladder is counting. Traders pricing the same public-health risk surface also trade the pandemic 2026 odds alongside this board.
Timing is the quiet factor. The count only climbs, so a rung that clears stays cleared, and a late-autumn cluster still counts against the December 31 line.
The market resolves December 31, 2026, against the U.S. measles case count for the calendar year as published by the Centers for Disease Control and Prevention. Each rung resolves Yes if the confirmed national total reaches or exceeds that rung's number and No if it does not. The agency updates the figure weekly, counts only cases confirmed and notified to it as of noon on Thursday, and assigns each case to a year by the epidemiological week of rash onset, so the final tally can still be revised after the last weekly post of the year. Because the count accumulates, a threshold that has already been passed stays settled at Yes.
For adjacent public-health and tail-risk contracts, compare the Ebola pandemic 2026 odds and the natural disaster 2026 odds, both of which price low-probability threshold events on the same calendar-year clock. Browse the full tech prediction markets hub for more science and biotech boards trading across Kalshi and Polymarket.
Resolves December 31, 2026, against the U.S. measles case count for the calendar year as reported by the Centers for Disease Control and Prevention. The market is a ladder of fixed thresholds running from 3,000 cases through 12,500 cases; each rung resolves Yes if the confirmed national total reaches or exceeds that rung's number and No if it does not. The CDC's published full-year tally is the source of truth. It updates weekly, counts only confirmed cases notified to the agency as of noon on Thursday, and assigns each case to a year by the epidemiological week of rash onset, so preliminary counts are subject to revision after the final weekly post. Because the count accumulates, a rung whose threshold has already been cleared stays settled at Yes, and any platform-specific tie-breaking or void rules apply if the official count is unavailable at resolution.
The market is a ladder of CDC case-count thresholds from 3,000 up through 12,500, each priced separately on Kalshi and Polymarket. As of August 31, 2026 the board's center of gravity sits on the 5,000 rung, up from 4,500 two weeks earlier, with the low thresholds near settled and the 10,000-and-up rungs in single digits. The live board above carries the current price on every rung across roughly $8.6M in cumulative volume.
The CDC confirmed 2,903 measles cases as of August 27, 2026, the highest annual U.S. total since 1991. That figure already exceeds the 2,289 cases recorded across all of 2025, with 37 new outbreaks logged in 2026 and 94% of cases, 2,737 of 2,903, outbreak-associated.
It resolves December 31, 2026, against the U.S. measles case count for the calendar year as reported by the CDC. Each rung resolves Yes if the confirmed national total reaches or exceeds that threshold, and the count only climbs, so a cleared rung stays settled at Yes.
Both Kalshi and Polymarket list case-count thresholds for 2026, and Prediction Genius groups them into one ladder so the two books can be compared on each shared rung, including the 4,000 and 10,000 levels. Several rungs such as 4,500 and 6,000 are carried by only one of the two books, so those show a single price rather than a cross-platform pair.
Pennsylvania announced two measles-associated deaths on August 25, 2026, the first U.S. measles deaths of the year, one of them a newborn. The CDC has not added them to its national count while it reviews whether measles caused or contributed to the deaths. Three deaths were attributed to the 2025 Southwest outbreak.
Watch the weekly CDC update each Thursday and the Pennsylvania and Ohio chains, which added 86 and 73 cases in recent single weeks and are what lift the 6,000-and-up rungs. The Pan American Health Organization's review of U.S. measles elimination status in November 2026 is the other date on the calendar before the December 31, 2026 resolution.