Thousands of South American coffee farmers are fighting the fungus called "coffee rust" in order to continue supplying the world-wide demand without growing prices, according to The Associated Press.

Because the fungus has no cure, and warmer climate conditions expecting to encourage its spread, farmers are bracing for a long, hard battle to survive, the AP reported.

The National Coffee Association of Guatemala, known as Anacafe, says some 100,000 direct coffee jobs have also dried up due to the lower coffee production, according to the AP.

Farmers are having to replace old trees with new coffee plants that better resist the rust, and cutting back existing trees in the hope they'll spring new foliage, according to the AP. It will be two to three years before the new plants produce the bright red cherries that hold the valuable beans.

The spread of rust has prompted growers to adopt new measures, such as "stumping," the practice of pruning trees of all infected vegetation in hopes of encouraging them to regrow with greater vibrancy, the AP reported. They are also using fungicides and installing shade covers, which appear to help keep the fungus at bay.

Rust also has hit farms in Southern Mexico, which produces much of the region's shade-grown coffee, and where the government is leading a sweeping replanting project, according to the AP.

"We have old, unproductive coffee plantations that haven't been pruned. In some case they're 40 years old," said Belisario Dominguez Mendez, who heads up coffee issues for Mexico's Agriculture Department, the AP reported. "Coffee rust is a good pretext to transform the coffee industry in Mexico."

With little government help, and farms falling below the break-even point, farmers have had to lay off workers due to lack in the funds needed to replant, according to the AP.

With many rural towns dependent on coffee production, observers fear widespread job losses and producers in the Guatemalan highlands have lost, on average, between a third and 60 percent of their income in the last year, according to the United Nations, the AP reported.

The United Nations is providing emergency food aid to 14,000 Guatemalan households that have lost income due to rust, but it is still less than 10 percent of the 160,000 homes estimated by the government nutrition agency to need such help, according to theAP.