Disease surveillance
What a reported dengue case means
Why suspected cases, confirmed cases and severe cases differ.
Measuring human suffering
to help reduce it
We estimate the scale of suffering across events to help people compare their human impact, recognize overlooked harm, and inform decisions about where to focus attention and support.
We use a proposed measure called the Universal Suffering Unit (USU). One USU represents the modeled pain of a six-hour reference kidney-stone episode. Our estimates combine how many people suffer, how intensely and for how long. Case counts and death tolls alone cannot capture all three dimensions.
Early estimates of selected experiences · Reported deaths shown separately
Event list
We’re actively adding events and broadening the types of suffering covered.
10 events sorted by coverage date, newest first.
| Event / included experience | Category | Period / coverage | Estimated USU | Reported deaths | Population modeled | Details |
|---|---|---|---|---|---|---|
| Nepal floodsDistress in displacement sites | Natural disaster | 4–9 Sep 2026 · site snapshot | 0.11 million | 1,367Broader flood event, same report | 3,629people in 37 sites | Report |
| DR Congo EbolaAcute illness, including fatal cases | Disease outbreak | Through 7 Sep 2026 | 0.24 million | 3,267Confirmed-case population | 6,757confirmed cases | Report |
| Mozambique floodsDistress in accommodation centres | Natural disaster | 29 Jan 2026 · centre snapshot | 3.1 million | Not availableNot given in selected report | Over 100,730people in 112 centres | Report |
| Brazil dengueAcute dengue symptoms | Disease outbreak | 2024 · weeks 1–23 | 59.9 million | 3,643Same reporting period | 7.87 millionreported cases | Report |
| Mexico dengueAcute dengue symptoms | Disease outbreak | 2024 · weeks 1–23 | 0.64 million | 26Same reporting period | 83,997reported cases | Report |
| Peru dengueAcute dengue symptoms | Disease outbreak | 2024 · weeks 1–23 | 1.9 million | 207Source discrepancy: summary says 203 | 249,843reported cases | Report |
| Rio Grande do Sul floodsInitial displacement distress | Natural disaster | 24 May 2024 · cohort snapshot | 17.7 million | 163Whole flood event, as of 24 May | About 580,000displaced people | Report |
| Bangladesh dengueAcute dengue symptoms | Disease outbreak | 1 Jan – 7 Aug 2023 | 0.53 million | 327Same reporting period | 69,483lab-confirmed cases | Report |
| Paraguay chikungunyaAcute chikungunya symptoms | Disease outbreak | 1 Oct 2022 – 11 Mar 2023 | 1.3 million | 52Probable / confirmed subset | 81,037reported cases | Report |
| Pakistan floodsInitial displacement distress | Natural disaster | 7 Oct 2022 · population snapshot | 240.8 million | At least 1,700Whole flood event, as reported 7 Oct | About 7.9 milliondisplaced people | Report |
USU estimates are approximate and assumption-based. They cover selected experiences, not every consequence of an event. Deaths remain separate. Read the method and assumptions.
The method
How we estimate suffering
Universal Suffering Units (USU) put an assumed intensity and duration alongside the number of people or episodes reported. We use shared representative courses, with each choice explained in the report. If a report separates fatal illness from other cases, each case receives one course and the groups are added together.
USU = count × average days × 24 × average intensity ÷ 47.25
One USU is a stipulated six-hour kidney-stone pain reference, totaling 47.25 intensity-hours. The scale is a convention; exact intensity assignments remain judgments.
Follow a calculation
Every report shows the source count, assumed course and arithmetic behind its headline.
See the Brazil dengue calculation →Understand the assumptions
The same condition and course type use the same assumptions across events, with the reasoning explained in every report.
Explore the common method →Further reading
Understand the numbers
Our background guides explain the statistics used to describe suffering. They cover broader topics and different reporting periods; they are not the event estimates above.
All background guides →Displacement
People displaced or movements recorded?
How to read the population behind a displacement estimate.
Questions about WSI
What can a USU number tell us?
Comparisons, uncertainty, coverage and why deaths stay separate.