Deaths Attributed to Heat, Cold, and Other Weather Events in the United States, 2006-10

NCHS has just released a report, “Deaths Attributed to Heat, Cold, and Other Weather Events in the United States, 2006-10,” which provides an in-depth look at the approximately 10,000 weather related deaths that occurred in the U.S. over that five-year span. In particular, the report examined the following causes of death: exposure to excessive natural heat (including heat stroke, sun stroke, or all); exposure to excessive natural cold (including hypothermia); and deaths attributed to floods, storms, or lightning.

NCHS has tallied weather-related deaths for years, but because of changes in the International Classification of Diseases (ICD) coding system over time, comparing past decades of weather-related deaths is difficult, if not impossible, particularly for deaths from excessive heat and cold.

DEATHS BY LIGHTNING ON THE DECLINE?

The CDC WONDER data base allows users to research these causes of death, in some cases going back to 1968. A look at the number of lightning deaths shows that from 1968 to 1978 there were 1,253 deaths from being struck by lightning – an annual average of about 114 deaths over that 11-year span. From 1979 to 1998, there were 1,589 lightning deaths, an annual average of about 79.5 deaths over that two-decade period. From 1999 to 2005, there were 365 lightning deaths, an annual average of a little over 52 deaths per year. The new 2006-2010 report shows 182 lightning deaths over that five-year span – an annual average of about 36.5 deaths per year. And 2011 data – the last year for available national data – show that 24 people were killed by lightning in the U.S. that year. So are lightning deaths on the decline in the U.S.? It would appear so.

Lightning deaths, which have had a single, independent ICD code for over the past four-plus decades, are the only of these weather-related deaths that are somewhat comparable.

STORMS & FLOODS – “CATACLYSMS”

From 1968 to 1978, the ICD-8 codes lumped both storms and floods together with other natural disasters like earthquakes and mudslides into one “Cataclysm” category. The ICD-9 codes (1979-1998) separated storms and floods from earthquakes, mudslides, etc. and during that 20-year period documented that storms and floods accounted for about 80% of all “cataclysm” deaths from (WONDER shows there were 2,196 deaths from storms and floods from 1979 to 1998 – an annual average of about 110 deaths per year). From 1968 to 1978, there were 2,683 deaths from all cataclysms – including any that were earthquakes, mudslides, etc.

From 1999 to 2005, there were 1,431 deaths from storms and floods, an annual average of over 204 deaths per year. However, 2005 was the year of Hurricane Katrina (and the less lethal but also devastating Hurricane Rita), which resulted in a spike in the number of these deaths. In the new 2006-2010 study, there were 464 deaths from storms and floods – an annual average of just under 93 deaths per year.

Comparing excessive heat and excessive cold-related deaths over the long term becomes virtually impossible using the WONDER data base, as prior to 1979 there was no distinction made between deaths from heat and cold that were weather-related vs. man-made.