Tara Smith is an associate professor of epidemiology at the University of Iowa and the co-director of the Center for Emerging Infectious Diseases. At Aetiology ( http://scienceblogs.com/aetiology), she writes about the changing world of diseases. Follow her on Twitter as @aetiology. Questions and answers have been edited.
Q: When did you discover your interest in infectious disease?
High school was the era of The Hot Zone and The Coming Plague and all the Ebola stuff. I was always kind of a science nerd, and I ended up reading those books within a short period of time and really liked them. I was thinking pre-med in college. But when I got there, I realized that wasnt really what I wanted to do. The college I went to had a school of public health, so I ended up dabbling in some of their epidemiology classes and found that I really liked germ stuff.
Q: How has modern society impacted how diseases develop?
Diseases can now go from one part of the world to another in less than 24 hours. There are a lot of ecological events that make it much easier for diseases to emerge. Landscape clearing, deforestation people are moving into areas where previously humans hadnt really had a lot of contact. We think of that in Africa and developing areas, but we had the same thing here in the U.S. with the emergence of Lyme disease, where we were moving out of the cities into rural areas.
We also have the technology now to identify pathogens we couldnt 10 years ago. With the advent of metagenomics and things where you can sequence everything in a particular persons blood, a liter of seawater or bat poop, were able to discover pathogens that previously we couldnt have cultured out.
Q: What are some of the challenges associated with assessing a diseases impact?
Its difficult, especially in areas where we dont have good surveillance, to try to get accurate numbers. For H7N9 flu, we saw people coming into hospitals with severe infections. But anything thats hospital-based, youre only going to catch the sickest of the sick. So we need to go back out into communities and see how many people are getting mild cases of this who were missing because theyre not coming into the hospitals. The hard part is knowing whats going on in places where people dont have a health care contact rural Africa or even in rural Iowa.