“We’re not responding to a research-driven question,” says Brooks, the principal investigator for the study coordinated through the World Bank’s Office of the Compliance Advisor/Ombudsman (CAO), the governing body of the World Bank’s private sector lenders. “This is an urgent public health emergency.”

The economic and social repercussions are huge: the disease hits primarily younger men working in various industries, leaving families in need of assistance. Brooks became involved in the study after former employees of Ingenio San Antonio (ISA), a sugar producer that received a loan from the World Bank, filed a complaint to the CAO. ISA employs thousands of workers in the states of León and Chinandega. The former workers blame the company—in particular, agricultural chemicals—for the outbreak. It is a sensitive, complex situation that is highly political in nature.

“Our first research report found no evidence that agrichemicals are causing chronic kidney disease here,” says Brooks, who leads a team of epidemiologists; nephrologists; and occupational, environmental health, and preventive medicine experts. Former workers met this conclusion with disbelief, and heated community meetings followed. Public education regarding the research process is an integral part of the study.

Brooks found that this is not a small-scale epidemic; it affects manual workers in hot climates from Mexico to Costa Rica, and even Sri Lanka, India, and Egypt. In developed countries, chronic kidney disease is typically caused by diabetes or hypertension, but this pattern does not bear out with this epidemic. The characteristics of the work environment are leading researchers to hypothesize that the disease has to do with heat stress. ISA addressed the concern by shortening the workday and introducing more water breaks, but more research is needed.

“We’re trying to broaden the funding to pursue different causes, but the one we are giving priority to has to do with working in a hot climate: insufficient hydration, likely acting with other factors we do not yet know,” says Brooks, who is optimistic about obtaining grant support to continue the research program. “It’s been three years of thinking about it every day. There’s always a deadline. It’s a long, wearing process, full of highs and lows. But it’s the project of a lifetime. I’m drawing on everything I’ve done before to make this work and find the cause.”