Thousands of people died in the months following Hurricane Maria, according to an independent investigation.
The study estimates that 2,975 more people died between September 2017 and February 2018 compared to the same period a year earlier.
The report, conducted by George Washington University's Milken Institute School of Public Health, was commissioned by the governor of Puerto Rico amid calls for a more rigorous investigation into the hurricane's death toll after the government estimated it had killed just 64 people.
The 2,975 "excess deaths" represent a 22 percent spike in the usual number of deaths during the same period in a year without a storm, according to the study.
It also found that certain groups, including those living in the poorest municipalities, and males over the age of 65, were more prone to death.
"The results of our epidemiological study suggest that, tragically, Hurricane Maria led to a large number of excess deaths throughout the island. Certain groups _ those in lower income areas and the elderly _ faced the highest risk," said Carlos Santos-Burgoa, the principal investigator of the project and global health professor at GW Milken Institute SPH. "We hope this report and its recommendations will help build the island's resilience and pave the way toward a plan that will protect all sectors of society in times of natural disasters," he said.
Rep. Nydia Velazquez, D-N.Y., who was born in Puerto Rico, used the study's findings to trash the federal government's inadequate response to the hurricane.
"Once again, we have yet more mounting evidence about the enormity of the tragedy that befell Puerto Rico last year. These numbers are only the latest to underscore that the federal response to the hurricanes was disastrously inadequate and, as a result, thousands of our fellow American citizens lost their lives. Notably, this study also confirms that lower income communities disproportionately suffered the greatest loss of life," she said in a statement.
The study also highlighted a serious lack of communication between the local government agencies in charge of reporting an accurate death toll, and a lack of training for how to properly certify disaster-related deaths, leading to a significant official undercount.
"The official government estimate of 64 deaths from the hurricane is low primarily because the conventions used for causal attribution only allowed for classification of deaths attributable directly to the storm. e.g., those caused by structural collapse, flying debris, floods and drownings," the report says. "During our broader study, we found that many physicians were not oriented in the appropriate certification protocol. This translated into an inadequate indicator for monitoring mortality in the hurricane's aftermath."
President Donald Trump, after the hurricane, downplayed the disaster's devastating effect on the island.
"If you look at a real catastrophe like Katrina, and you look at the tremendous hundreds and hundreds and hundreds of people that died ... 16 people versus in the thousands. You can be very proud of all of your people," he said in the days after the storm.
Hurricane Katrina claimed more than 1,800 lives, according to the National Hurricane Center.
