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icon for How many West Nile neuroinvasive disease cases will be reported among New York City residents in 2026?
Climate & Science·Science

How many West Nile neuroinvasive disease cases will be reported among New York City residents in 2026?

icon for How many West Nile neuroinvasive disease cases will be reported among New York City residents in 2026?
Climate & Science·Science

How many West Nile neuroinvasive disease cases will be reported among New York City residents in 2026?

Fewer than 20 43%

20 to 34 39%

35 to 49 16%

50 or more 7%

Polymarket
NEW

Fewer than 20 43%

20 to 34 39%

35 to 49 16%

50 or more 7%

Polymarket
NEW

Fewer than 20

$781 Vol.

43%

20 to 34

$669 Vol.

39%

35 to 49

$1,438 Vol.

16%

50 or more

$262 Vol.

7%

This market resolves based on the total number of West Nile neuroinvasive disease cases (encephalitis, meningitis, and acute flaccid paralysis) reported among New York City residents in 2026, as published by the New York City Department of Health and Mental Hygiene on its West Nile Virus Reports page at nyc.gov/site/doh/health/health-topics/west-nile-virus-reports.page. Cases are counted as whole numbers, so each outcome covers a distinct range with no overlap or gap. The 2026 count shown on the source as of January 1, 2027 is the starting figure. If the DOHMH publishes or revises the 2026 count on or after January 1, 2027, this market will resolve based on the count shown on the source at 11:59 PM ET on the 14th day after the first such update, or on March 31, 2027, 11:59 PM ET, whichever comes first. If no such update occurs, this market will resolve on March 31, 2027, 11:59 PM ET, based on the 2026 count shown on the source at that time. If no 2026 count has been published on the source by March 31, 2027, 11:59 PM ET, this market will resolve based on the sum of 2026 West Nile neuroinvasive disease case counts reported by CDC ArboNET for the five New York City counties (Bronx, Kings, New York, Queens, and Richmond). Revisions published after this market resolves will not be considered. If the DOHMH changes its reporting format or URL structure, the closest equivalent NYC Health Department publication of 2026 West Nile neuroinvasive case data will be used.Recent confirmation of just one neuroinvasive West Nile case in New York City as of mid-August, despite sharply elevated mosquito pool positives compared with 2025, anchors trader consensus near even odds between fewer than 20 and 20–34 total cases. Warmer temperatures have extended transmission seasons in recent years, correlating with the rise from a 16-case annual average (2012–2021) to 31 (2022–2025), while peak mosquito activity and human exposure typically continue through September. Citywide larval control, variable rainfall, and the concentration of severe outcomes among older adults introduce uncertainty about whether incidence will remain suppressed or align with the higher recent baseline before reporting closes.

This market resolves based on the total number of West Nile neuroinvasive disease cases (encephalitis, meningitis, and acute flaccid paralysis) reported among New York City residents in 2026, as published by the New York City Department of Health and Mental Hygiene on its West Nile Virus Reports page at nyc.gov/site/doh/health/health-topics/west-nile-virus-reports.page.

Cases are counted as whole numbers, so each outcome covers a distinct range with no overlap or gap.

The 2026 count shown on the source as of January 1, 2027 is the starting figure.

If the DOHMH publishes or revises the 2026 count on or after January 1, 2027, this market will resolve based on the count shown on the source at 11:59 PM ET on the 14th day after the first such update, or on March 31, 2027, 11:59 PM ET, whichever comes first. If no such update occurs, this market will resolve on March 31, 2027, 11:59 PM ET, based on the 2026 count shown on the source at that time.

If no 2026 count has been published on the source by March 31, 2027, 11:59 PM ET, this market will resolve based on the sum of 2026 West Nile neuroinvasive disease case counts reported by CDC ArboNET for the five New York City counties (Bronx, Kings, New York, Queens, and Richmond). Revisions published after this market resolves will not be considered. If the DOHMH changes its reporting format or URL structure, the closest equivalent NYC Health Department publication of 2026 West Nile neuroinvasive case data will be used.
Volume
$3,150
End Date
Mar 31, 2027
Market Opened
Aug 20, 2026, 5:18 PM ET

Resolution Source

https://www.nyc.gov/site/doh/health/health-topics/west-nile-virus-reports.page

Resolver

0x69c47De9D...
This market resolves based on the total number of West Nile neuroinvasive disease cases (encephalitis, meningitis, and acute flaccid paralysis) reported among New York City residents in 2026, as published by the New York City Department of Health and Mental Hygiene on its West Nile Virus Reports page at nyc.gov/site/doh/health/health-topics/west-nile-virus-reports.page. Cases are counted as whole numbers, so each outcome covers a distinct range with no overlap or gap. The 2026 count shown on the source as of January 1, 2027 is the starting figure. If the DOHMH publishes or revises the 2026 count on or after January 1, 2027, this market will resolve based on the count shown on the source at 11:59 PM ET on the 14th day after the first such update, or on March 31, 2027, 11:59 PM ET, whichever comes first. If no such update occurs, this market will resolve on March 31, 2027, 11:59 PM ET, based on the 2026 count shown on the source at that time. If no 2026 count has been published on the source by March 31, 2027, 11:59 PM ET, this market will resolve based on the sum of 2026 West Nile neuroinvasive disease case counts reported by CDC ArboNET for the five New York City counties (Bronx, Kings, New York, Queens, and Richmond). Revisions published after this market resolves will not be considered. If the DOHMH changes its reporting format or URL structure, the closest equivalent NYC Health Department publication of 2026 West Nile neuroinvasive case data will be used.
This market resolves based on the total number of West Nile neuroinvasive disease cases (encephalitis, meningitis, and acute flaccid paralysis) reported among New York City residents in 2026, as published by the New York City Department of Health and Mental Hygiene on its West Nile Virus Reports page at nyc.gov/site/doh/health/health-topics/west-nile-virus-reports.page. Cases are counted as whole numbers, so each outcome covers a distinct range with no overlap or gap. The 2026 count shown on the source as of January 1, 2027 is the starting figure. If the DOHMH publishes or revises the 2026 count on or after January 1, 2027, this market will resolve based on the count shown on the source at 11:59 PM ET on the 14th day after the first such update, or on March 31, 2027, 11:59 PM ET, whichever comes first. If no such update occurs, this market will resolve on March 31, 2027, 11:59 PM ET, based on the 2026 count shown on the source at that time. If no 2026 count has been published on the source by March 31, 2027, 11:59 PM ET, this market will resolve based on the sum of 2026 West Nile neuroinvasive disease case counts reported by CDC ArboNET for the five New York City counties (Bronx, Kings, New York, Queens, and Richmond). Revisions published after this market resolves will not be considered. If the DOHMH changes its reporting format or URL structure, the closest equivalent NYC Health Department publication of 2026 West Nile neuroinvasive case data will be used.Recent confirmation of just one neuroinvasive West Nile case in New York City as of mid-August, despite sharply elevated mosquito pool positives compared with 2025, anchors trader consensus near even odds between fewer than 20 and 20–34 total cases. Warmer temperatures have extended transmission seasons in recent years, correlating with the rise from a 16-case annual average (2012–2021) to 31 (2022–2025), while peak mosquito activity and human exposure typically continue through September. Citywide larval control, variable rainfall, and the concentration of severe outcomes among older adults introduce uncertainty about whether incidence will remain suppressed or align with the higher recent baseline before reporting closes.

This market resolves based on the total number of West Nile neuroinvasive disease cases (encephalitis, meningitis, and acute flaccid paralysis) reported among New York City residents in 2026, as published by the New York City Department of Health and Mental Hygiene on its West Nile Virus Reports page at nyc.gov/site/doh/health/health-topics/west-nile-virus-reports.page.

Cases are counted as whole numbers, so each outcome covers a distinct range with no overlap or gap.

The 2026 count shown on the source as of January 1, 2027 is the starting figure.

If the DOHMH publishes or revises the 2026 count on or after January 1, 2027, this market will resolve based on the count shown on the source at 11:59 PM ET on the 14th day after the first such update, or on March 31, 2027, 11:59 PM ET, whichever comes first. If no such update occurs, this market will resolve on March 31, 2027, 11:59 PM ET, based on the 2026 count shown on the source at that time.

If no 2026 count has been published on the source by March 31, 2027, 11:59 PM ET, this market will resolve based on the sum of 2026 West Nile neuroinvasive disease case counts reported by CDC ArboNET for the five New York City counties (Bronx, Kings, New York, Queens, and Richmond). Revisions published after this market resolves will not be considered. If the DOHMH changes its reporting format or URL structure, the closest equivalent NYC Health Department publication of 2026 West Nile neuroinvasive case data will be used.
Volume
$3,150
End Date
Mar 31, 2027
Market Opened
Aug 20, 2026, 5:18 PM ET

Resolution Source

https://www.nyc.gov/site/doh/health/health-topics/west-nile-virus-reports.page

Resolver

0x69c47De9D...
This market resolves based on the total number of West Nile neuroinvasive disease cases (encephalitis, meningitis, and acute flaccid paralysis) reported among New York City residents in 2026, as published by the New York City Department of Health and Mental Hygiene on its West Nile Virus Reports page at nyc.gov/site/doh/health/health-topics/west-nile-virus-reports.page. Cases are counted as whole numbers, so each outcome covers a distinct range with no overlap or gap. The 2026 count shown on the source as of January 1, 2027 is the starting figure. If the DOHMH publishes or revises the 2026 count on or after January 1, 2027, this market will resolve based on the count shown on the source at 11:59 PM ET on the 14th day after the first such update, or on March 31, 2027, 11:59 PM ET, whichever comes first. If no such update occurs, this market will resolve on March 31, 2027, 11:59 PM ET, based on the 2026 count shown on the source at that time. If no 2026 count has been published on the source by March 31, 2027, 11:59 PM ET, this market will resolve based on the sum of 2026 West Nile neuroinvasive disease case counts reported by CDC ArboNET for the five New York City counties (Bronx, Kings, New York, Queens, and Richmond). Revisions published after this market resolves will not be considered. If the DOHMH changes its reporting format or URL structure, the closest equivalent NYC Health Department publication of 2026 West Nile neuroinvasive case data will be used.

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Frequently Asked Questions

"How many West Nile neuroinvasive disease cases will be reported among New York City residents in 2026?" is a prediction market on Polymarket with 4 possible outcomes where traders buy and sell shares based on what they believe will happen. The current leading outcome is "Fewer than 20" at 43%, followed by "20 to 34" at 39%. Prices reflect real-time crowd-sourced probabilities. For example, a share priced at 43¢ implies that the market collectively assigns a 43% chance to that outcome. These odds shift continuously as traders react to new developments and information. Shares in the correct outcome are redeemable for $1 each upon market resolution.

"How many West Nile neuroinvasive disease cases will be reported among New York City residents in 2026?" is a newly created market on Polymarket, launched on Aug 20, 2026. As an early market, this is your opportunity to be among the first traders to set the odds and establish the market's initial price signals. You can also bookmark this page to track volume and trading activity as the market gains traction over time.

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The current frontrunner for "How many West Nile neuroinvasive disease cases will be reported among New York City residents in 2026?" is "Fewer than 20" at 43%, meaning the market assigns a 43% chance to that outcome. The next closest outcome is "20 to 34" at 39%. These odds update in real-time as traders buy and sell shares, so they reflect the latest collective view of what's most likely to happen. Check back frequently or bookmark this page to follow how the odds shift as new information emerges.

The resolution rules for "How many West Nile neuroinvasive disease cases will be reported among New York City residents in 2026?" define exactly what needs to happen for each outcome to be declared a winner — including the official data sources used to determine the result. You can review the complete resolution criteria in the "Rules" section on this page above the comments. We recommend reading the rules carefully before trading, as they specify the precise conditions, edge cases, and sources that govern how this market is settled.