Elevated West Nile virus activity in New York City mosquitoes—now exceeding 1,500 positive pools, roughly double last year’s pace—combined with the first human cases reported in mid-to-late August is driving trader expectations toward 20–34 neuroinvasive disease cases for the full 2026 season. Recent years show an average of 25–31 West Nile neuroinvasive disease cases annually among city residents (range 16–36 from 2021–2025), with transmission peaking in August–September before declining by October. Official surveillance from the NYC Health Department and CDC indicates widespread borough-level detection and intensified control measures, yet the early and sustained vector positivity raises the risk of outcomes in the 35–49 range if conditions favor continued transmission. Historical data place fewer than 20 or 50-plus cases as less probable given current trends and reporting thresholds.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · UpdatedHow many West Nile neuroinvasive disease cases will be reported among New York City residents in 2026?
How many West Nile neuroinvasive disease cases will be reported among New York City residents in 2026?
20 to 34 44%
35 to 49 27%
Fewer than 20 11%
50 or more 4.0%
$10,368 Vol.
$10,368 Vol.
Mar 31, 2027
Fewer than 20
11%
20 to 34
44%
35 to 49
27%
50 or more
10%
20 to 34 44%
35 to 49 27%
Fewer than 20 11%
50 or more 4.0%
$10,368 Vol.
$10,368 Vol.
Mar 31, 2027
Fewer than 20
$2,883 Vol.
11%
20 to 34
$4,527 Vol.
44%
35 to 49
$2,455 Vol.
27%
50 or more
$504 Vol.
10%
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.Elevated West Nile virus activity in New York City mosquitoes—now exceeding 1,500 positive pools, roughly double last year’s pace—combined with the first human cases reported in mid-to-late August is driving trader expectations toward 20–34 neuroinvasive disease cases for the full 2026 season. Recent years show an average of 25–31 West Nile neuroinvasive disease cases annually among city residents (range 16–36 from 2021–2025), with transmission peaking in August–September before declining by October. Official surveillance from the NYC Health Department and CDC indicates widespread borough-level detection and intensified control measures, yet the early and sustained vector positivity raises the risk of outcomes in the 35–49 range if conditions favor continued transmission. Historical data place fewer than 20 or 50-plus cases as less probable given current trends and reporting thresholds.
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.
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.
Market Opened: Aug 20, 2026, 5:18 PM ET
Volume
$10,368End Date
Mar 31, 2027Market Opened
Aug 20, 2026, 5:18 PM ETResolver
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.Elevated West Nile virus activity in New York City mosquitoes—now exceeding 1,500 positive pools, roughly double last year’s pace—combined with the first human cases reported in mid-to-late August is driving trader expectations toward 20–34 neuroinvasive disease cases for the full 2026 season. Recent years show an average of 25–31 West Nile neuroinvasive disease cases annually among city residents (range 16–36 from 2021–2025), with transmission peaking in August–September before declining by October. Official surveillance from the NYC Health Department and CDC indicates widespread borough-level detection and intensified control measures, yet the early and sustained vector positivity raises the risk of outcomes in the 35–49 range if conditions favor continued transmission. Historical data place fewer than 20 or 50-plus cases as less probable given current trends and reporting thresholds.
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.
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
$10,368End Date
Mar 31, 2027Market Opened
Aug 20, 2026, 5:18 PM ETResolver
0x69c47De9D...Elevated West Nile virus activity in New York City mosquitoes—now exceeding 1,500 positive pools, roughly double last year’s pace—combined with the first human cases reported in mid-to-late August is driving trader expectations toward 20–34 neuroinvasive disease cases for the full 2026 season. Recent years show an average of 25–31 West Nile neuroinvasive disease cases annually among city residents (range 16–36 from 2021–2025), with transmission peaking in August–September before declining by October. Official surveillance from the NYC Health Department and CDC indicates widespread borough-level detection and intensified control measures, yet the early and sustained vector positivity raises the risk of outcomes in the 35–49 range if conditions favor continued transmission. Historical data place fewer than 20 or 50-plus cases as less probable given current trends and reporting thresholds.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · Updated
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