UCSF scientist Eva Harris, one of the winners of the prestigious MacArthur Foundation Fellowships announced yesterday, first witnessed 10 years ago the devastating impact of the tropical diseases she now studies.

Fresh out of Harvard and already having practiced science in Boston, Paris and Switzerland, she lit out for war-torn Nicaragua. She ended up at the Ministry of Health, full of ideas on how to use molecular biology -- the study of the mechanisms by which genetic blueprints lead to the production of proteins -- in the service of medicine.

Harris, a researcher in the department of stomatology laboratory of renowned molecular biologist Nina Agabian, was honored by the MacArthur Foundation for developing techniques to diagnose and treat disease in Central and South America.

Harris, who is in Bolivia this week, will receive a $210,000 unrestricted, “no strings attached” stipend covering the next five years. Because of her grassroots efforts over the years, according to the MacArthur Foundation, scientists in Nicaragua, Ecuador, and other countries initiated and expanded their use of DNA diagnostic technologies to identify the protozoan, bacillar, and viral strains which lead to outbreaks of infectious diseases. These technologies are also being integrated into the public health systems of these countries. Harris is establishing a nonprofit foundation, Sustainable Sciences Institute, to carry out appropriate technology transfer and to foster collaboration at an international level.

In the past several years, the 31-year-old scientist has been energized by the experience of having her own, positive impact, through the training of Latin American scientists to diagnose tropical diseases. With vaccines non-existent, diagnosis leading to treatment serves as the foundation for disease containment in these countries.

In Nicaragua in 1987, she began working to apply molecular diagnostics to the chronic, debilitating disease caused by the microscopic parasite Leishmania, by detecting bits of genes unique to the organism. Inspired by early success, Harris began organizing training workshops in Nicaragua while simultaneously earning her doctorate at UC Berkeley. Each workshop trained 20 doctors and public health workers and adapted modern biotechnology to diagnose leishmaniasis and other, deadly infectious diseases -- cholera, dengue fever, and tuberculosis. These scourges affect countries too poor to attract the interest of companies that develop and market diagnostic kits in industrialized nations.

The success of the program relied on the enthusiasm, initiative and wherewithal of workshop graduates, as they sought to apply what they had learned to halt the spread of disease and to treat the infected. Harris later enlisted other students and researchers at Berkeley and UCSF to help conduct other workshops.

Harris’ “appropriate technology” is based on a laboratory technique called the polymerase chain reaction (PCR), used to replicate unique genetic material of interest -- from a disease pathogen, for example -- millions of times, so that it can serve as an easily detected genetic fingerprint.

The methods are cheaper and faster than older, standard diagnostic techniques, and they work in places such as Nicaragua, where the availability of electricity and water is unreliable. Harris and her colleagues found ways to simplify PCR for identifying agents of disease under difficult conditions. For example, samples could be boiled to free DNA for testing, eliminating steps that would be required to extract it with solvents. Leishmania species can be detected in skin lesions, and did not need to be grown in controlled laboratory conditions for weeks at a time. Water contaminated with the bacterium Vibrio cholera can be identified directly after filtering.

Harris and her Latin American collaborators overcame many small obstacles in adapting the technology for use in new settings. In Quito, Ecuador, for instance, the 9,000-foot altitude caused water to boil off before becoming hot enough to carry out one step of the diagnostic procedure, so the scientists layered oil over the water bath to contain it and raise the temperature. Her workshops eventually attracted prominent physicians from university hospitals, as well as rural doctors from the Amazon. “Many of the participants had heard of molecular biology, but it was perceived as sophisticated, mysterious and unattainable,” Harris says. “This was the first large-scale introduction of molecular technology into Ecuador.”

Later workshops trained scientists to use the new techniques to diagnose tuberculosis in the severely affected Andean community of Zumbahua, dengue fever in the coastal city of Guayaquil, and leishmaniasis in the southern region of Loja, where the disease is widespread. An unanticipated spin-off of these simple, hands-on courses is their application in the United States to provide training in molecular biology to high school teachers, as well as high school and college students. Harris, for example, has introduced courses into the San Francisco Unified School District through the UCSF Science and Health Education Partnership program. During the courses, participants identify DNA from disease-causing organisms, and from the students' own hair. By adapting methods used in infectious disease detection and forensics, the lessons highlight the real-world relevance of laboratory science.

Jeffrey Norris in the News Services office contributed to this report.

1st appeared 6/18/97