Regents' Professor: Carlos Castillo-Chavez

Carlos Castillo-Chavez mixes mathematics research with mentoring and social change

March 23, 2006

Carlos Castillo-Chavez says he’s always been interested in social issues. He grew up in the 1960s in Mexico, during the social revolution that was spreading around the world.

After immigrating to the United States at age 22, he found that little by little the serious issues of the underprivileged began to sink in even more. Social issues like HIV, tuberculosis, alcohol abuse and Ecstasy use seemed to be more prevalent in the underprivileged population, and Castillo-Chavez began to wonder how mathematics might help limit their impact in these communities.

Regents' and President's Professors Carlos Castillo-Chavez is among six ASU faculty members who have been awarded Regents Professor appointments for 2006. Regents’ Professors are marked by excellence in teaching, exceptional achievements in research or other creative activities, and national and international distinction in their fields. Named by the Arizona Board of Regents, they serve as advisers to the university president and take on a broader role as consultants and teachers throughout the university. The other members of this year's Regents' Professor class are: Cordelia Candelaria, Chicana and Chicano Studies; Carlos Castillo-Chavez, Mathematics and Statistics Department; Douglas Montgomery, Industrial Engineering Department; George Poste, Biodesign Institute and School of Life Sciences; Edward Prescott, Economics Department, Rogier Windhorst, Physics and Astronomy Department. Six outstanding faculty named ASU Regents’ Professors This year ASU is honoring the first class of ASU President's Professors. This new prestigious award, is designed to reward enthusiasm and innovation in teaching, the ability to inspire original and creative work by students, mastery of subject matter and scholarly contributions. Inaugural awardees are Randall Cerveny, professor of geography; Alice Christie, associate professor of technology and education; Ian Gould, professor of chemistry and biochemistry; and the late Paul Rothstein, associate professor of industrial design. ASU selects inaugural President's Professors The Regents' and President's Professors will all be inducted in a ceremony April 27.

His mother, with a fourth-grade education, and his father, who served in the military, fed his passion for learning. He plunged into academics, in two-and-a-half years earning bachelor’s degrees in Spanish and mathematics, and later a master’s degree in mathematics. He earned a mathematics doctorate as well, then joined the faculty at Cornell University.

As a mathematical epidemiologist, Castillo-Chavez seeks the answers to these questions:

• What are the key mechanisms associated with the spread of diseases?

• How can we prevent their growth?

• How can we eliminate them?

Finding answers to those questions is what propels Castillo-Chavez’s research.

“These issues never leave your mind,” he says. These diseases “destroy many communities and stop people from reaching their potential,” he says, adding that he believes that what drives disease and most of its problems is social dynamics.

“The training we used to get in math never focused on these issues,” he says. “In the last decade or so, HIV (the human immunodeficiency virus) triggered a new trend: Whatever we do mathematically has to have social relevance.”

Using HIV – the virus that causes acquired immune deficiency syndrome (AIDS) – as an example, Castillo-Chavez explains how mathematical research might stop a disease from moving to a higher level. In a country like Botswana, if 70 percent of the truck drivers used condoms 50 percent of the time, will that one social change significantly decrease the prevalence or HIV?

Whether it’s HIV, SARS (severe acute respiratory syndrome) or avian flu, “there is a lot of demand now for the use of mathematics to understand complex disease systems,” he says. “This opens a new window for people who have strong social concerns to do math.”

Over his 18-year tenure at Cornell, Castillo-Chavez became one of the most prominent mathematicians in the country. As an expert in epidemiological modeling, his work led to new insights on how behavior patterns affect the spread of disease. During the 2003 SARS epidemic in Toronto, he developed a model that accurately predicted the number of cases and estimated how many more people would have been infected had public-health authorities not taken measures to control the outbreak.

Today, Castillo-Chavez is one of the newest Regents’ Professors in ASU’s College of Liberal Arts and Sciences, as well as the Joaquin Bustoz Jr. Professor of Mathematical Biology. He is sought out for his opinion and advice by the CIA, pharmaceutical companies, the National Science Foundation, the Department of Defense, other universities and audiences around the world, most recently in China (where he holds an honorary professorship) and Latin America.

Castillo-Chavez also is committed to mentoring the next generation of gifted mathematicians. While at Cornell, Castillo-Chavez founded the Mathematical and Theoretical Biology Institute (MTBI) to provide research opportunities for undergraduate and graduate students with an interest in math. His goal: to dramatically increase the number of underrepresented minority students and women earning mathematics doctoral degrees.

“Nationally, the representation of minorities in the math and science disciplines is a tragedy,” he says. “My personal goal is to increase their representation by at least 50 percent.”

Over the past 10 years, he has mentored more than 240 undergraduate students and more than 80 graduate students, including post-doctoral students.

Last year, when Castillo-Chavez came to ASU, he brought the MTBI with him, believing he can have a larger impact here than at an Ivy League school like Cornell. With Arizona’s rapidly growing Hispanic population, “I can be accessible to a lot more people like myself,” he says.

Castillo-Chavez used to play soccer, and he used to play the guitar. By his own admission, he has lived an eclectic life. But these days, it’s all about research.

“One of the big problems that one has as a minority scientist is that, if you dedicate all your time to addressing the social concerns of the minority community without having a significant research program, that’s a recipe for failure as a scientist,” he says. “So I must do research every day. Fortunately, I also really like it.”

Still, when asked to compare the satisfaction that comes from his research discoveries to the satisfaction that comes from helping to mold young minds, Castillo-Chavez is certain of the answer: mentoring wins.

Castillo-Chavez is among the top research contributors to literature on the progression of diseases, yet he says, “No matter how many papers you publish, you have to realize that your contributions to knowledge are really minimal. But changing the life of a young person is something very visible. What could be more rewarding than that?”

Hughes, with the College of Liberal Arts and Sciences, can be reached at (480) 965-6375 or (carol.hughes@asu.edu). Grant, with the College of Liberal Arts and Sciences, can be reached at (480) 965-9106 or (barby.grant@asu.edu).