A fungus called Coffee rust, or la roya, has once again destroyed crops in Central America. Experts say that climate change is to be blamed for the dwindling coffee production in the region.

La roya has gained a stronger foothold this year in the coffee-producing regions of Central America, New York Times reported. Rise in global temperature has helped the fungus spread in the high-altitude regions.

Arabica beans that grow in temperatures between 18°C and 22°C, account for some 70 percent of coffee produced in Brazil. Even 1°C rise in temperature could lead to a 25 percent loss in Brazil's famous Arabica coffee.

Hemileia Vastatrix fungus known as "La Roya" is the scourge of coffee-producers across the South America. The fungus thrives in warm weather and attacks the leaves of coffee bush.

Millions of people have lost their only source of income, according to media reports.

The NYT report describes the plight of a certain Román Lec, who grows coffee in San Lucas Tolimán, Guatemala. Coffee rust withered a major part of his crop last year and this year, the disease has struck harder, making it impossible for Lec to earn a livelihood.

"There are nights when you cannot sleep, thinking how to pay back the money," Lec, 65, told the New York Times.

The Guardian had recently reported that farmers in Nicargua, too, are witnessing coffee crop shortages of as much as 50 percent due to coffee rust.

Along with farmers, La roya has snatched the livelihood of merchants and migrant workers. Teenagers are forced to quit school to start working on coffee farms.

The International Coffee Organization had estimated that the La roya cut as many as 74,000 jobs in Central America in 2013, the Wall Street Journal had reported.

"Roya has exposed the depth of the social and economic problems in terms of people's vulnerability to the market and to climate change," said Peter Loach, the Guatemala director of Mercy Corps, an aid agency, according to New York Times. "What makes it different and complicated is that it's a slow-onset natural disaster over two to three years."

Experts have warned that rising temperatures will lead to bad, expensive coffee in the future.

"The rise in global temperature is of great concern for us in the coffee industry because it will - and has already started - putting the supply of quality coffee at great risk," said Dr Tim Schilling, executive director of the World Coffee Research programme, based at Texas A&M University, according to the Guardian. "It is also obvious that increasing temperatures - as well as extreme weather events - have a very negative affect on production. Over the long term, you will definitely see coffee prices going up as a result of climate change."