The Arab Spring uprising and subsequent conflicts in the Middle East and North Africa have lowered life expectancy in countries such as Syria, Yemen, Tunisia and Egypt, jeopardizing two decades of health gains, experts said on Wednesday.

Between 2010 and 2013, Yemen, Tunisia and Egypt lost some three months of the average person’s life expectancy, while the war in Syria has erased six years off average life expectancy, they said in a research published in The Lancet Global Health journal.

“Life expectancy decline is traditionally regarded as a sign that the health and social systems are failing,” said Ali Mokdad, a professor at the University of Washington, who led the research.

Conflict in Syria has killed more than 250,000 people and displaced some 11 million since it began more than five years ago as pro-democracy protests.

Many of the health gains achieved by countries in the region are at risk of stalling as fighting has damaged basic infrastructure while millions are at risk of disease outbreaks caused by water shortages and poor sanitation, the experts said.

“Along with population growth and aging, these ongoing conflicts have dramatically increased the burden of chronic diseases and injuries and many health workers have fled for safer shores,” said Mokdad.

Syria is falling behind countries sub-Saharan Africa in reducing child mortality, with infant deaths rising by 9.1 percent a year between 2010 and 2013.

Across the region, heart disease was the number one cause of death in 2013, overtaking diarrheal diseases and respiratory infections. γ