A research update on the demography and injury burden of victims of New Zealand earthquakes between 2010 and 2014

Abstract

Identifying what causes injuries and understanding who is most at risk during an earthquake will help inform ways to reduce the risk of injury and improve rescue and medical strategies. This study compares the number of people exposed to recent Aotearoa New Zealand earthquakes with the severity of the injury, demography, and where the injury occurred. We approximate how many people were exposed to each earthquake by combining estimates of ground shaking with models of where people are located at different times. We analysed injury data from all earthquakes and their aftershock periods by patient age and sex, location, scene of injury, and date of injury. The high injury burdens of the Christchurch earthquakes largely reflect daytime shaking. Twice as many females as males were injured in all the earthquakes we studied. People between 40-59 years were most at risk of injury. Where people were at the time of shaking influenced their risk of injury. Two-thirds of injuries occurred at home, followed by 14% in commercial locations and 6.5% on roads and streets. This pattern was repeated within the data for each sex. The results suggest that the greater the intensity of shaking and the size and density of the population, the higher the total injury burden.