How much does case definition change the apparent size of a dengue epidemic? Paired laboratory-confirmed and suspected case series, 2018–2024

Surveillance systems report dengue under different case definitions — laboratory-confirmedversus suspected/probable — and aggregators typically publish one series without the other.This dataset pairs both series for the same country and year, from named originatingauthorities, so the size of the definitional gap can be measured directly. In the 2024 epidemic the gap is large: Brazil reports 6,579,385 laboratory-confirmed casesand 10,330,277 suspected — a 57% difference in the apparent size of the same event. CONTENTS alertx_dengue_2024_by_country.csv 22 countries, 2024, both series, authority named alertx_dengue_annual_global_2018_2024.csv global annual series, both measures dataset_metadata.json method, limitations, SHA-256 checksums CHECKSUMS.sha256 integrity METHODCounts are aggregated by the same module every AlertX surface uses (Rules A–F: period-fit,running totals differenced rather than summed, national reporting superseding subnational forthe same population), over calendar-year windows with full prior history so cumulativecounters anchor correctly. Metric classification is by source. Confirmed and suspected areseparate columns and are NEVER summed — the suspected series generally contains the confirmedone, so adding them double-counts. LIMITATIONS* Reported surveillance counts, not modelled incidence or true burden. Most dengue infections are mild or asymptomatic and are never reported at all.* Coverage is uneven and PAHO-region reporting is far more complete than South and South-East Asia. The absence of a country means it did not report to us, not that it had no dengue.* Country coverage in the wider AlertX collection grew from 22 reporting countries in 2018 to 99 in 2024, so year-over-year change generally conflates epidemiology with coverage. Dengue was checked specifically and is a partial exception: Brazil reports in every year and the suspected panel is a stable 7–8 countries throughout, so the 2024 rise is a real epidemic.* Recent calendar years remain incomplete and rise as sources report on their lag. Only complete calendar years are published, released once the following year has also closed. ATTRIBUTIONCite ENCLAI AlertX and the originating public-health authority named against each row.Underlying figures originate with those authorities, whose own terms continue to apply wherestricter than this licence.