New estimate is based on the finding that the number of deaths from September 2017 to February 2018 was up 22% year on year

This article is more than 2 years old

This article is more than 2 years old

Puerto Rico has raised the official death toll from Hurricane Maria to 2,975 people – a dramatic increase on the previous official figure of 64 – almost a year after the devastating storm struck the island.

Puerto Rico quietly moves to update Hurricane Maria death toll from 64 to 1,427 Read more

The death toll was changed for the first time since December, following the publication of new research by George Washington University’s Milken Institute School of Public Health.

“We never anticipated a scenario of zero communication, zero energy, zero highway access,” Puerto Rico’s governor, Ricardo Rosselló, told reporters. “I think the lesson is to anticipate the worst.”

This is the first official change to the death toll following efforts by journalists, activists and academics to get the government to officially acknowledge the scale of devastation.

Rosselló told reporters the island could have been better prepared for the hurricane, which hit on 20 September 2017, causing an island-wide electricity outage and telecommunications failures that made it nearly impossible for people to contact loved ones and get help for weeks after the storm.

Play Video 9:50 Puerto Rico after Hurricane Maria: 'We're American, too, why don't they help?' – video

“Yes, I made mistakes,” Rosselló said. “Yes, in hindsight, things could have been handled differently.”

Nearly a year on from the hurricane, Puerto Ricans are still struggling and more than 300,000 people have fled the island for the mainland.

Rosselló said the report provided a foundation for the government to improve its response to hurricanes and other disasters. He also announced the creation of a “9/20” commission to determine what such improvements should look like.

Certain populations are identified in the report as being more vulnerable to natural disasters, including people who lived below the poverty level, the elderly and people who have chronic illnesses and need access to medications and medical equipment such as dialysis.

“A lesson from this [report] is that efforts for assistance and recovery need to focus as much as possible on lower-income areas, on people who are older, who are more vulnerable,” said Lynn Goldman, dean of the Milken institute.

The finding is almost twice the government’s previous, unofficial estimate, included in a recent report to Congress, that said there were 1,427 more deaths in the three months after the storm than the average for the same period over the previous four years.

George Washington University researchers found that the number of deaths from September 2017 to February 2018 was up 22% year on year.

Facebook Twitter Pinterest A display of pairs of shoes pay tribute to Hurricane Maria’s victims in San Juan. Photograph: Alvin Baez/Reuters

The university researchers said the official count from the hurricane, which hit with huge force on 20 September as a series of tropical storms and hurricanes raged through the region, was low, in part, because doctors were not trained in how to certify deaths after a disaster.

Nydia Velazquez, a Democratic New York congresswoman, said the report shows the US government failed the people of Puerto Rico.

“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,” she said in a statement. There is no national standard on how to count disaster-related deaths.

The researchers said they counted deaths over the span of six months, a much longer period than usual because so many people were without power during that time.

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“That caused a number of issues,” Goldman said, adding that people were forced to exert themselves physically or were exposed to intense heat without fans or air conditioning. “It’s fairly striking that you have so many households without electricity for so long. That’s unusual in the US after a disaster.”

Donald Trump was lambasted for the government’s slow response to the disaster. The president later visited the island and appeared to complain about the cost of relief, while also making a display out of throwing rolls of paper towel to a group gathered to hear his address.

This is the first official change to the death toll following efforts by journalists, activists and academics to get the government to officially acknowledge the scale of devastation.

Researchers said the actual number of excess deaths was estimated to be in the range of 2,658 to 3,290. Researchers said the next stage of assessing the death toll includes examining death certificates and interviewing family and friends of the deceased to determine if those deaths should be attributed to the storm.

Associated Press contributed to this report