How many total cases of dengue fever will the World Health Organization report in Brazil in the first half of 2025?

Started Mar 07, 2025 06:00PM UTC
Closed Jul 01, 2025 07:01AM UTC

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In the News 2025

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In 2024, a record number of cases of dengue fever were reported across the globe, with a heavy concentration in Brazil (Guardian, MSN [Washington Post], World Health Organization). The question will be suspended on 30 June 2025 and the outcome determined once data through June 2025 are first available (WHO - Global Dengue Surveillance, click "Country and region data" at the top of the page, change "Country" to "Brazil," confirm that "Year of data" is set to "2025," and click "Apply filters." In the first half of 2024, a total of 9,400,831 cases were reported, up from 2,502,144 over the same period in 2023.

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The question closed "At least 2.5 million, but fewer than 3.5 million" with a closing date of 1 July 2025.

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Possible Answer	Correct?	Final Crowd Forecast
Fewer than 1.5 million		1%
At least 1.5 million, but fewer than 2.5 million		1%
At least 2.5 million, but fewer than 3.5 million		74%
At least 3.5 million, but fewer than 4.5 million		13%
At least 4.5 million, but fewer than 5.5 million		3%
At least 5.5 million, but fewer than 6.5 million		3%
At least 6.5 million, but fewer than 7.5 million		3%
At least 7.5 million, but fewer than 8.5 million		2%
At least 8.5 million, but fewer than 9.5 million		1%
At least 9.5 million, but fewer than 10.5 million		1%
10.5 million or more		1%