A mysterious epidemic is devastating the Pacific coast of Central America, killing more than 24,000 people in El Salvador and Nicaragua since 2000 and striking thousands of others with chronic kidney disease at rates unseen virtually anywhere else. Scientists say they have received reports of the phenomenon as far north as southern Mexico and as far south as Panama.
Last year it reached the point where El Salvador’s health minister, Dr. Maria Isabel Rodriguez, appealed for international help, saying the epidemic was undermining health systems.
Wilfredo Ordonez, who has harvested corn, sesame and rice for more than 30 years in the Bajo Lempa region of El Salvador, was hit by the chronic disease when he was 38. Ten years later, he depends on dialysis treatments he administers to himself four times a day.
“This is a disease that comes with no warning, and when they find it, it’s too late,” Ordonez said as he lay on a hammock on his porch.
Many of the victims were manual laborers or worked in sugar cane fields that cover much of the coastal lowlands. Patients, local doctors and activists say they believe the culprit lurks among the agricultural chemicals workers have used for years with virtually none of the protections required in more developed countries. But a growing body of evidence supports a more complicated and counterintuitive hypothesis.
The roots of the epidemic, scientists say, appear to lie in the grueling nature of the work performed by its victims, including construction workers, miners and others who labor hour after hour without enough water in blazing temperatures, pushing their bodies through repeated bouts of extreme dehydration and heat stress for years on end. Many start as young as 10. The punishing routine appears to be a key part of some previously unknown trigger of chronic kidney disease, which is normally caused by diabetes and high-blood pressure, maladies absent in most of the patients in Central America.
“The thing that evidence most strongly points to is this idea of manual labor and not enough hydration,” said Daniel Brooks, a professor of epidemiology at Boston University’s School of Public Health, who has worked on a series of studies of the kidney disease epidemic.
Because hard work and intense heat alone are hardly a phenomenon unique to Central America, some researchers will not rule out manmade factors. But no strong evidence has turned up.