It’s been 20 years since Esteban González Burchard took a trip to Chicago that changed his life. The asthma researcher had been to the Windy City before, so tourism wasn’t on his agenda. Rather, he was there to attend the American Thoracic Society Conference for the first time. And he was on a mission.

The then-senior medical resident at Boston’s Brigham and Women’s Hospital had given himself a steep challenge: Read all the posters within his field, epidemiology. (Just so you know, there were hundreds of them.)

Amid the flood of research abstracts, images, and data, one graphic caught his eye. Colored in blue hues, a map from the Centers for Disease Control and Prevention depicted asthma prevalence among Latinos in the United States. A quick glance seemed to tell a simple tale: Latinos in New York, Massachusetts, and other northeastern states experienced asthma at significantly higher rates than Latinos living in other parts of the country.

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