Thanks to climate change, coffee rust's ideal habitat seems to be spreading as higher elevations and more northern areas become warmer

Last February, Guatemala declared a state of national emergency. Coffee rust, a devastating fungal disease that parasitizes coffee plant leaves, had struck the Latin American nation. Soon, Mexico, El Salvador, Honduras, Nicaragua, Panama and Costa Rica—all major coffee-producing countries—reported similar outbreaks at their plantations. At this point, Wired reports, the disease has reached epidemic proportions in the region.

Regional production fell by 15 percent last year, putting nearly 400,000 people out of work, and that’s just a taste of what’s to come. The next harvest season begins in October, and according to the International Coffee Organization, crop losses could hit 50 percent.

These crops tend to be a variety of coffee called Arabica, which is prized by coffee connoisseurs. It’s not the coffee snobs but the farmers and workers who will really suffer, however. After coffee rust takes hold, the disease is difficult to get under control. Many famers can’t afford expensive fungicides, and plants may take years to recover on their own, Wired reports.

Nobody knows precisely why the outbreak reached such extraordinary levels this year, though several factors are implicated. The most prominent is climate: In the past, environmental conditions at high Central American altitudes were not especially conducive to the fungus, which requires warm, humid air to thrive, said coffee rust specialist Cathy Aime of Purdue University.

Scientists first recorded the disease in Kenya in 1861, and it turned up in Sri Lanka a few years later. By the 1920s, it had spread throughout Africa and Asia by the 1920s. It wasn’t until the 1970s that it made its way to Central America. According to Wired, this trend will probably worsen: Thanks to climate change, coffee rust’s ideal habitat—warm, humid conditions—seems to be spreading as higher elevations and more northern areas warm up.