Researchers at the George Washington University Milken Institute School of Public Health (GW Milken Institute SPH) published a paper in The Lancet Planetary Health that provides the data and methodology underlying an independent report that estimated there were 2,975 excess deaths in Puerto Rico during the six-month period after Hurricane Maria. The new study also tracks mortality trends during that period. The study found that people living in all areas of Puerto Rico faced an elevated risk of mortality during the first two months after the storm, but this risk elevation was most prominent, and prolonged, for people living in the poorest parts of the island.
“This study offers public health officials a method to accurately size up the excess mortality due to natural disasters – not just in Puerto Rico but all over the world,” said Dr. Carlos Santos-Burgoa, a professor of global health at GW Milken Institute SPH and lead author of the study. “All jurisdictions should use total excess mortality as a practical, timely and sensitive way to monitor deaths after natural disasters. Public health officials can then step in with rapid interventions and influence the actions of other sectors in order to protect the most vulnerable populations.”
A collaboration between researchers at GW Milken Institute SPH and the University of Puerto Rico Graduate School of Public Health, the study was based on official death certificates and other mortality data recorded from Sept. 1, 2017, through the end of February 2018. Using a state-of-the-art mathematical model that accounted for annual and seasonal variability, migration, sex, age and socioeconomic status of municipalities, the team compared the total number of deaths that were observed to occur during that time to the number that would have been expected to occur in a “normal” year.
The researchers found that 43 percent (1,271) of the total number of excess deaths were estimated to have occurred during the first two months (September and October) after the hurricane made landfall in the seaside municipality of Yabucoa, Puerto Rico. However, the excess deaths continued to be observed throughout the study period, with 347 excess deaths in November, 479 in December, 558 in January and 320 in February.
All areas of the island had elevated death rates in the first two months after the storm. However, for high and middle-income municipalities, the death rates fell back to the expected levels by November and December 2017 respectively.
In contrast, areas of the island with the lowest levels of socioeconomic development saw a continued excess rate of mortality through the end of the study’s observation period. Over the entire period, the risk of dying was 22 percent higher than expected but was up to 60 percent for people living in the poorest municipalities of Puerto Rico.
“Assessment of the differential and persistent risk of excess mortality from Hurricane Maria in Puerto Rico,” was published online October 11 in The Lancet Planetary Health.