The Peace Corps spent more than $40 million providing benefits to 3,305 returned volunteers through workers compensation programs over a five-year period, the U.S. Government Accountability Office said.

The office on Friday released a report comparing workers comp benefits provided to Peace Corps volunteers under the Federal Employees' Compensation Act with benefits provided to employees of the U.S. Agency for International Development contractors and subcontractors working outside the United States under the Defense Base Act.

The report found that from July 1, 2009, through June 30, 2014, the Peace Corps paid about $41 million to provide reimbursements for medical expenses to 3,305 returned volunteers with service-related injuries and illnesses.

The Peace Corps provides benefits to returned volunteers who sustain illnesses or injuries connected to their service, according to the report. The most common illnesses and injuries among volunteers that received workers comp include mental, emotional and nervous conditions, dental conditions, infectious or parasitic diseases, and other nonclassified diseases.

The U.S. Government Accountability Office is not making any recommendations at this time regarding other options for providing health benefits to address the needs of returned Peace Corps volunteers with service-related injuries and illnesses, the report states.

In that same timeframe, meanwhile, USAID paid about $67 million to cover contractors' premium costs to provide insurance to an unknown number of overseas employees.

While USAID doesn't track the total number of contractor employees for which they provided this insurance, its insurer reported paying about $11.4 million to cover the cost of medical care and other expenses for about 487 contractor employees with illnesses or injuries that weren't caused by war hazards, according to the report. Meanwhile, the insurer said it paid about $11.7 million for about 174 employees with illnesses or injuries that were caused by war hazards.

The most common illnesses and injuries, not including those caused by war hazards, among employees of USAID contractors were strained body parts, broken or fractured body parts and infections, as well as death, according to the report. The most common condition caused by war hazards was mental anguish, along with death.