VAERS Japan — Heatmaps by Month × Vaccine (2021–2022, cumulative)

One page per vaccine brand (Pfizer or Moderna; comparator = all other Japan vaccine reports in the same cumulative period) and recvdate month in 2021–2022 for Japan (upper(splttype) LIKE 'JP%'). Each month is cumulative: the page for a month uses all reports received from Jan 2021 through that month, as in the article’s cumulative analyses. Each page has PRR, MGPS (EBGM) and RGPS treemaps side by side (PRR, MGPS and RGPS) in the gradient view (green→black→red) and in Bootstrap colors (light gray→blue→green→orange→red). After BMJ 2026;394:e100806. Use the Custom Search Builder below for compound filters (e.g. Month between 2021-06-01 and 2021-12-31 AND Vaccine reports ≥ 100, or the custom Month → In year / ≥ 100 reports conditions), or the quick Search box. All underlying data are stored as parquet files in data/ (jp_cells.parquet, jp_totals.parquet, jp_scores.parquet, jp_pages.parquet).

Date handling: each month is stored and filtered as a real ISO date — the 1st of that month (data-order/data-filter="YYYY-MM-01", column type date, DateTime picker in SearchBuilder) — so sorting, “before / after / between” and the custom “In year” condition are chronological, not lexicographic on the “Jul 2021” label.

The pages and this listing are regenerated from the parquet datasets by the PRR/MGPS/RGPS heatmap pipeline. Only 2021–2022 are generated. Months/vaccines with very few Japan reports show few or no tiles.