While officials in Puerto Rico placed the official death toll from last year's Hurricane Maria at 64, researchers from Harvard believe the death toll was actually in the thousands.
According to Harvard's study, there were an estimated 4,645 deaths directly or indirectly tied to the hurricane, which struck the island in September. Harvard estimated a mortality rate of 14.3 deaths per 1.000 people from September 20 through December 31, 2017 in Puerto Rico.
Harvard said in its study that it believes its estimate is rather conservative due to a "survivor bias."
Harvard conducted the study by performing a random survey of 3,299 households in Puerto Rico.
"In our survey, interruption of medical care was the primary cause of sustained high mortality rates in the months after the hurricane, a finding consistent with the widely reported disruption of health systems," the study says. "Growing numbers of persons have chronic diseases and use sophisticated pharmaceutical and mechanical support that is dependent on electricity. Chronically ill patients are particularly vulnerable to disruptions in basic utilities, which highlights the need for these patients, their communities, and their providers to have contingency plans during and after disasters."
Part of why there the death toll might have been underreported is due to how hurricane-related deaths are counted. In order to have a death counted as storm related, bodies had looked at by a medical examiner, which required a body to be transported to San Juan, or the medical examiner to travel to remote locations. With a lack of electricity and blocked roads, some bodies were likely buried before the government could count fatalities.
Maria is considered the third-costliest hurricane in US history.
