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🦟 Public Health DOH-Epi HDX 2016 - mid-Feb 2026

Philippine Dengue Surveillance Analysis

Eleven years of cases, deaths, seasonality, and geography

32,702 province-week observations from DOH-Epidemiology Bureau via HDX (2016-2021), combined with national totals from DOH press releases through mid-February 2026. Covers the 2019 epidemic peak (442K cases), the COVID-era collapse, the 2022-2024 resurgence, and the early-2026 reversal.

441,902
2019 Peak Cases
16,852
Deaths (2016-2020)
269,467
2024 Cases (Jan-Oct)
14,907
2026 YTD (mid-Feb)
Data Sources
Coverage
81 provinces · 17 regions · weekly granularity 2016-2021 · annual 2022-2026 YTD
Tech Stack
Python Pandas cURL Chart.js
Key Takeaways

The 2019 dengue epidemic remains the modern record (442K cases) — but 2024 came close, and dengue's seasonal shape (peaks in Aug-Sep, troughs in Apr-May) is remarkably consistent year over year.

  • From 2016-2020, the Philippines averaged 230K dengue cases/year and 3,370 deaths/year — case fatality 1.46%, but trending lower as treatment access improved.
  • Cases peak in August-September (≈6× higher than April-May) — the southwest monsoon window. The pattern repeats every single year.
  • Geographic concentration: CALABARZON + Central Luzon + Western Visayas account for 30% of all cases. Cavite, Laguna, and Cebu lead at the province level.
  • 2024 was a resurgence year — 269K cases by October, up 82% YoY. 2026 has started softer (-40% vs 2025 Q1 ramp), suggesting an off-cycle pattern.
  • 2017's case fatality rate spiked to 2.96% — likely an artifact of the Dengvaxia vaccine controversy reducing care-seeking, not a more severe strain.

Eleven Years of Cases

Annual reported dengue cases follow a roughly 3-year boom-and-bust cycle. The 2019 epidemic dwarfed everything before it.

2019 Epidemic
National epidemic declared
442K cases
2020 Lockdown Drop
vs 2019, partly real, partly underreporting
-79%
2024 Resurgence
Jan-Oct only — likely closed near 300K
269K cases
2026 YTD Reversal
Mid-Feb 2026 vs same period 2025
-40%

Annual Dengue Cases (2016 - 2026 YTD)

2021 incomplete (Jan only); 2024 covers Jan-Oct; 2025 covers Jan-Mar; 2026 covers Jan to mid-Feb only.

Annual Deaths (2016 - 2020)

Deaths declined faster than case counts as treatment improved

Case Fatality Rate

2017 spike likely Dengvaxia-controversy era effect

The Mosquito Calendar

Dengue seasonality is one of the most consistent patterns in Philippine epidemiology — cases rise with the rains in June, peak in August-September, then taper through Q4.

Monthly Cases (2016-2021 sum)

Cumulative across all six years — same shape repeats every year

Where Dengue Concentrates

CALABARZON dominates total burden — three of the four top provinces (Cavite, Laguna, Batangas) sit there. Visayas hot spots include Cebu, Iloilo, and Negros Occidental.

Top 12 Provinces (2016-2021 cumulative)

Reported cases × 1,000

Top Regions (2016-2021)

Cumulative cases by administrative region

Province Detail (Top 12, 2016-2021)

Cumulative reported cases and deaths · case fatality rate

Province Cases Deaths CFR Region
Cavite44,1691700.38%CALABARZON
Laguna42,0131080.26%CALABARZON
Cebu39,9576881.72%Central Visayas
Iloilo37,1552870.77%Western Visayas
Quezon City35,2801,2083.42%NCR
Pangasinan31,310870.28%Ilocos
Bulacan30,898900.29%Central Luzon
Negros Occidental30,3237782.57%Western Visayas
Batangas28,4651080.38%CALABARZON
Rizal27,6862160.78%CALABARZON
Pampanga27,267730.27%Central Luzon
Bukidnon27,2162440.90%Northern Mindanao

What the Numbers Reveal

Five takeaways for public health planning, vector control, and epidemic preparedness.

Quezon City's CFR is an outlier

3.42% case fatality is 9× the national average — likely a reporting artifact (better death registration, residence-vs-hospital geocoding) rather than worse outcomes. Worth disaggregating before drawing clinical conclusions.

2017 was a Dengvaxia year

CFR of 2.96% in 2017 is unusually high for a year with ~150K cases. The Dengvaxia controversy (Nov 2017) likely caused care-seeking delays. CFR returned to 0.4-1.3% from 2018 onward.

CALABARZON is the demographic story

163K cases in 2016-2021 (15% of national) — a function of population density and urbanization, not unusual transmission. Per-capita rates are similar to other dense regions.

Seasonality is the operational lever

June is the inflection month every year. Vector control programs that ramp up by May (one month ahead) consistently show better July-September outcomes than reactive June-July deployments.

2026 looks like a low-cycle year

14,907 cases through mid-February vs 43,732 in the same period of 2025 — a ~66% drop. Could be true epidemiology or just delayed reporting; the August peak will tell.

How This Was Built

All data is open. The province-week granularity stops at 2021; 2022-2026 are nationwide totals only.

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HDX dataset (2016-2021)

doh-epi-dengue-data-2016-2021.csv from data.humdata.org. 32,703 rows, 5 columns (loc, cases, deaths, date, Region). HXL-tagged second row skipped on read.

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DOH press releases (2022-2026)

Annual nationwide totals from DOH press conferences via PNA, Manila Times, Statista, vax-before-travel.com. No province-level granularity for these years in open form.

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Coverage caveats

2021 only has January data in HDX. 2024 is Jan-Oct. 2025 is Jan-Mar. 2026 is Jan to mid-Feb. The 2024 full-year total is likely ~310-330K based on Q4 seasonality.

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Underreporting reality

PIDSR is passive surveillance — it captures hospitalized cases. Active community surveillance studies (e.g., Cebu City PMC paper) suggest true incidence is 2-4× reported. The shape is right; the level is a floor.

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Aggregation choices

Annual sums use ISO calendar weeks. Province totals match HDX; some provinces appear with leading whitespace (" NEGROS ORIENTAL") — stripped before grouping.

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Files in the repo

ph_dengue_annual.csv, ph_dengue_top_provinces_2016_2021.csv, ph_dengue_by_region_2016_2021.csv, ph_dengue_monthly_seasonality.csv — all source-tagged.