Global hunger has fallen more than a quarter since 2000, but conflict and climate shocks are beginning to reverse these gains, an annual global hunger index said.

Nearly half of the 119 countries surveyed had “serious,” “alarming” or “extremely alarming” hunger levels between 2012 and 2016, with war-torn Central African Republic worst affected, followed by Chad, Sierra Leone, Madagascar and Zambia. North Korea ranked 27th.

The United Nations said that global hunger levels have risen for the first time in more than a decade, now affecting 11 percent of the world’s population -- or 815 million people.

The index is based on levels of hunger in the general population, and rates of wasting, stunting and deaths among children under five years old.