Many of the deaths they found on the U.S. territory were caused by the interruption of health care, electricity and utility services after the hurricane decimated the island.
Hurricane Maria made landfall on Puerto Rico as a Category 4 hurricane on Sept. 20, knocking power out to the entire island and leaving long-lasting damage in its wake.
The researchers, with the Harvard T.H. Chan School of Public Health and other institutions, surveyed nearly 3,300 households across Puerto Rico and asked people about causes of death, displacement and loss of infrastructure. The study estimated a mortality rate of 14.3 deaths per 1,000 persons during the three months after the hurricane hit.
That toll was then extrapolated to the island as a whole and compared to the mortality rate for the same time period in 2016, according to the study.
“Our estimates also indicate that mortality rates stayed high throughout the rest of the year,” the researchers wrote.
While the official death toll remains at 64, several news organizations had already placed the number of island deaths from Hurricane Maria at more than 1,000. And after months of pressure, the Puerto Rican government ordered an independent in-depth review of the death toll, calling in George Washington University to lead it.
The results are expected this summer, Mina Radman, a spokeswoman for the university’s Milken Institute School of Public Health, said in an email, adding that the institute did not have anyone available to comment on the Harvard study.
In a statement on the new study, Carlos R. Mercader, executive director of the Puerto Rico Federal Affairs Administration, said:
“The government of Puerto Rico welcomes the newly released Harvard University survey and we look forward to analyzing it. As the world knows, the magnitude of this tragic disaster caused by Hurricane Maria resulted in many fatalities. We have always expected the number to be higher than what was previously reported. That is why we commissioned The George Washington University to carry out a thorough study on the number of fatalities caused by Hurricane Maria which will be released soon. Both studies will help us better prepare for future natural disasters and prevent lives from being lost.”
Just a month ago, an island-wide blackout hit the island — seven months after the storm.
The mayor of San Juan, Carmen Yulín Cruz, an outspoken critic of the local and federal response to the hurricane, said in a series of tweets that the estimated death toll was “unthinkable” and asked if the government of Gov. Ricardo Rosselló will now believe the numbers are higher.
“There are many deaths caused by poor crisis management,” she tweeted. Adding in another post, “It took too long to understand the need for an appropriate response was NOT about politics but about saving lives.”