Elevated West Nile virus detection in over 1,450 NYC mosquito pools through late August 2026—nearly double last year’s pace with an early June onset—has supported the 20–34 case bin at 41.5% implied probability, consistent with the recent 2022–2025 average of 31 neuroinvasive cases annually. Only three confirmed West Nile neuroinvasive disease cases have been reported so far, aligning with the competing “fewer than 20” outcome at 36.5%. Peak transmission typically occurs in August–September, when most historical cases emerge; intensified larviciding, surveillance, and variable progression from asymptomatic infection to severe neuroinvasive illness (less than 1% of exposures) introduce uncertainty around final totals relative to the 16 cases recorded in 2025.
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 43%
Fewer than 20 36%
35 to 49 21%
50 or more 4.0%
NEW
NEW
Mar 31, 2027
Fewer than 20
36%
20 to 34
43%
35 to 49
21%
50 or more
7%
20 to 34 43%
Fewer than 20 36%
35 to 49 21%
50 or more 4.0%
NEW
NEW
Mar 31, 2027
Fewer than 20
$1,788 Vol.
36%
20 to 34
$2,764 Vol.
43%
35 to 49
$1,550 Vol.
21%
50 or more
$500 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.Elevated West Nile virus detection in over 1,450 NYC mosquito pools through late August 2026—nearly double last year’s pace with an early June onset—has supported the 20–34 case bin at 41.5% implied probability, consistent with the recent 2022–2025 average of 31 neuroinvasive cases annually. Only three confirmed West Nile neuroinvasive disease cases have been reported so far, aligning with the competing “fewer than 20” outcome at 36.5%. Peak transmission typically occurs in August–September, when most historical cases emerge; intensified larviciding, surveillance, and variable progression from asymptomatic infection to severe neuroinvasive illness (less than 1% of exposures) introduce uncertainty around final totals relative to the 16 cases recorded in 2025.
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
$6,602End 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 detection in over 1,450 NYC mosquito pools through late August 2026—nearly double last year’s pace with an early June onset—has supported the 20–34 case bin at 41.5% implied probability, consistent with the recent 2022–2025 average of 31 neuroinvasive cases annually. Only three confirmed West Nile neuroinvasive disease cases have been reported so far, aligning with the competing “fewer than 20” outcome at 36.5%. Peak transmission typically occurs in August–September, when most historical cases emerge; intensified larviciding, surveillance, and variable progression from asymptomatic infection to severe neuroinvasive illness (less than 1% of exposures) introduce uncertainty around final totals relative to the 16 cases recorded in 2025.
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
$6,602End Date
Mar 31, 2027Market Opened
Aug 20, 2026, 5:18 PM ETResolver
0x69c47De9D...Elevated West Nile virus detection in over 1,450 NYC mosquito pools through late August 2026—nearly double last year’s pace with an early June onset—has supported the 20–34 case bin at 41.5% implied probability, consistent with the recent 2022–2025 average of 31 neuroinvasive cases annually. Only three confirmed West Nile neuroinvasive disease cases have been reported so far, aligning with the competing “fewer than 20” outcome at 36.5%. Peak transmission typically occurs in August–September, when most historical cases emerge; intensified larviciding, surveillance, and variable progression from asymptomatic infection to severe neuroinvasive illness (less than 1% of exposures) introduce uncertainty around final totals relative to the 16 cases recorded in 2025.
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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