“Yard Flooding by Irrigation Canals Increased the Risk of West Nile Disease in El Paso, Texas,”
by Dr. Victor M. Cardenas
and colleagues was selected this year for the Annals of Epidemiology Award,
which recognizes the best article published in the journal over the past year. For the first ACE member highlight, we chose to feature the primary author of this award winning article. Dr. Cardenas, an Associate Professor in the Division of Epidemiology at the University of Texas-Health Science Center at Houston School of Public Health on the El Paso campus, became a fellow in 2006 and served on the Board of Directors from 2009 to 2011. He says that he decided to join ACE because, “there is a specific call in the original 1979 ACE bylaws to organize the professionals of the Americas, which I found very refreshing and appealing.” Initially educated as a physician at the National Autonomous University of Mexico, Dr. Cardenas became interested in epidemiology early in his career. He received training specialty training in epidemiology from the School of Public Health in Mexico, and the newly established Field Epidemiology Training Program, and later from Emory University Rollins School of Public Health where he obtained both an MPH and a PhD in Epidemiology. Dr. Cardenas’ career has largely focused on infectious disease surveillance and outbreak investigations, which prepared him for this research considering the effect of residential proximity to irrigation canals and the practice of yard flooding using water from these canals on the risk of West Nile disease in El Paso, Texas.
Dr. Cardenas became interested in the topic of West Nile disease in El Paso because as he mentioned, “I have followed the occurrence of West Nile Virus since 2003. I had noticed the striking pattern of occurrence along the Franklin Canal system and did the case-hypothetical control study since 2007, but the manuscript was rejected again and again. I decided to do the actual case-control study to validate the application of this approach to a topic that had been addressed only by ecological studies.” This study used both geospatial modeling and case-control interview data to determine the effects of living in proximity to irrigation canals, the use of yard flooding, both personally and by neighbors, and other factors on the risk of West Nile virus. From 2003 to 2010, 182 cases of West Nile virus were identified in El Paso with an age-adjusted incidence rate of 3.5 cases per 100,000 person-years. In the geospatial data analyses, the odds of living in the closest quintile to an irrigation canal were 5.7 times higher for cases compared to controls. And the risk of infection with West Nile virus based on the proximity to these irrigation canals may be related to the practice of yard flooding, since cases had 4.5 greater odds of seeing neighbors flooding their yards using water from nearby irrigation canals than controls. Dr. Cardenas and his colleagues concluded that the practice of flooding residential yards using water from irrigation canals is a risk factor for West Nile disease and that intervention efforts should focus on populations living near these irrigation canals. He also said that, “this factor may be at work in many other settings such as Maricopa Arizona, Fresco California, Boise Idaho, and other places where agricultural lands that used or still use water from irrigation canals became engulfed by urban sprawl.”
The Annals of Epidemiology award article is found here
and Dr. Cardenas can be contacted at Victor.Cardenas@uth.tmc.edu