Tomas Leon

Directory Info


Georgia Institute of Technology, BS Environmental Engineering, 2012
University of California, Berkeley, MS Environmental Health Sciences (Global Health & Environment), 2014


Robert C. Spear


A primary parasite of interest in Thailand is Opisthorchis viverrini, the Southeast Asian liver fluke, which is transmitted to humans via the consumption of raw and undercooked fish and has a complicated transmission cycle that also involves snails and other secondary hosts. O. viverrini and the related Clonorchis sinensis (Chinese liver fluke) are unique in being classified as Group 1 biological carcinogens by the IARC for causing cholangiocarcinoma, a highly fatal liver cancer.

The goal of my research is to investigate risk factors in aquaculture design, management, and maintenance that allow O. viverrini eggs, cercariae, and metacercariae to be transmitted through the system and enable the potential for human infection. Because numerous education and awareness campaigns have not succeeded in curbing consumption of raw fish in Thailand, my primary objective is to examine and mitigate environmental factors that influence the transmission of O. viverrini.

Selected Publications

Tomás León. Mathematical modeling of liver fluke transmission dynamics in aquaculture systems.  In Asian Neglected Tropical Diseases Conference. September 16-17, 2014. Khon Kaen, Thailand.

Tomás León, Despina Tsementzi, Chengwei Luo, Natasha DeLeon-Rodriguez, and Konstantinos Konstantinidis. The emergence of naturalized E. coli and its importance for fecal contamination testing. In the 111th American Society for Microbiology, General Meeting. May 21-25, 2011. New Orleans, LA, USA. 

Why I chose the Berkeley EHS program

I chose Cal EHS because of the unique and special opportunities that Berkeley the city, Berkeley the University, and the EHS program specifically had to offer me. I love living and working in such an intellectually and culturally vibrant environment and am privileged to have great friends and colleagues in Cal EHS.


Hiking around the world, reading works of fiction, volunteering at San Quentin, and worshiping at Christ Church Berkeley.