Biological disasters in the United States

How common are Biological disasters in the U.S.?

FEMA has issued 17 federal disaster declarations classified as biological between 2020 and 2021, affecting 15 states and territories. Each declaration represents a formal federal recognition that an event exceeded state and local response capacity, unlocking Public Assistance, Individual Assistance, or Hazard Mitigation Grant Program funding depending on the declaration class (DR, EM, or FM). Raw declaration counts therefore measure the federal response footprint, which is a lagging and thresholded indicator: smaller events handled entirely at the state level never appear, and declaration thresholds have been recalibrated over the dataset's multi-decade history.

This disaster type's footprint is thin and scattered across the map. The three states with the most biological declarations on record are NM (3 declarations), AL (1 declarations), AZ (1 declarations), consistent with how narrowly this hazard type is geographically concentrated. States with the fewest declarations, including WA (1), CA (1), NY (1), unsurprising given how rare a federal declaration of this type is anywhere in the country.

With so few declarations on record, the year-by-year pattern is necessarily sparse. The peak year on record was 2020, with 15 biological declarations issued that single year, a clustering driven by major multi-state events and the federal government's declaration cadence. The most recent year on record is 2021, with 2 declarations. Trends over the 1+ year history reflect how infrequently this disaster type crosses the federal declaration threshold at all.