Measles Passes 4,400 Cases, Yet 'At Least 4000' Term Average Drops

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Will Measles Cases Average 4,000 During Trump's Term? 2026 Alone Already Tops It

At least 4000 measles cases is already reached in 2026, but the average across Trump's term is not yet at that level. The CDC counted 4,410 confirmed US measles cases in 2026 as of Oct. 15, in data posted Oct. 16, versus 2,289 for all of 2025, according to the CDC. The Kalshi market "What will the average number of measles cases be during Trump's term?" resolves on a term average, so 2026 alone does not settle the question.

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What will the average number of measles cases be during Trump's term?

Each outcome's chance, from what traders are paying right now on Kalshi.

At least 4000In this story

64%

Kalshi1.54x65¢

At least 2000

97%

Kalshi1.03x97¢

At least 2500

90%

Kalshi1.09x92¢

At least 3000

87%

Kalshi1.09x92¢

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The weekly count rose by 330 cases, or 8.1%, from 4,080. That figure, as of Oct. 8, was the first time the 2026 total topped 4,000, as CBS News reported. The rising count did not lift the contract. On Kalshi, the "At Least 4000" contract fell from 81% to 65% over three days, a 16 percentage point drop. It traded at 65% on Oct. 22.

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How the Term Average Works for the 'At Least 4000' Contract

The CDC supplies two inputs. One is the full 2025 total of 2,289. The other is the 2026 year-to-date total of 4,410. By our arithmetic, those two years sum to 6,699 cases, an average of about 3,350 per year. That is below 4,000, even though 2026 on its own is well above it.

The denominator decides the rest of the math. Background reporting describes the window as the average annual count from 2025 through 2028. We could not confirm that from the contract's resolution text, so we do not calculate how many cases the later years would need to reach 4,000. The 2025 baseline sits about 1,700 cases below the threshold, so any multi-year average needs later years to run well above 4,000 to make up that gap.

We could not establish what caused the 16 percentage point drop. No cited source ties the selling to a specific report. The gap between the 2026 count and a multi-year average is the tension the price is weighing.

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What Could Move the 'At Least 4000' Market Next

The next CDC weekly update. The benchmark is last week's gain of 330 cases (8.1%). A faster pace lifts the 2026 total, which is the largest input the term average will absorb. A slower pace narrows how much 2026 can offset the low 2025 figure. The CDC reported 451 hospitalizations and 3 deaths across 47 jurisdictions in 2026. It also reported that 96% of cases were tied to 42 outbreaks.

Pennsylvania's outbreak. Local officials put the state's count at more than 1,200 cases and six deaths, according to Contagion Live. That death count exceeds the CDC's national tally of three, a gap the sources do not explain. The state has requested CDC Epi-Aid support, and a CDC disease detective is being deployed. Whether that response slows transmission will shape weekly growth through year-end. Outbreak Watch tracks the updates between CDC releases.

The final 2026 total. The year-end figure locks in the second input to the average. Once it is set, the remaining question is how the following years compare. Track the contract on the Trump-term measles average market page when the CDC publishes its full-year count in early 2027.