Success is Something to Sneeze At: Influenza Mortality in Cities that Participate in the Super Bowl
Stoecker, Charles, Nicholas Sanders, & Alan Barreca
American Journal of Health Economics | 2016 | 2(1): 125–143
Using county-level Vital Statistics of the United States data from 1974-2009, we employ a differences- in-differences framework comparing influenza mortality rates in Super Bowl-participating counties to non-participants. Having a local team in the Super Bowl causes an 18% increase in influenza deaths for the population over age 65, with evidence suggesting one mechanism is increased local socialization. Effects are most pronounced in years when the dominant influenza strain is more virulent, or when the Super Bowl occurs closer to the peak of influenza season. Mitigating influenza transmission at gatherings related to large spectator events could have substantial returns for public health.
Absolute Humidity, Temperature, and Influenza Mortality: 30 Years of County-Level Evidence from the United States
Barreca, Alan, & Jay Shimshack
American Journal of Epidemiology | 2012 | 176: S114-S122.
Recent research exploring associations between environmental factors and influenza outcomes has devoted substantial attention to the role of absolute humidity. However, the existing literature provides very little quantitative epidemiologic evidence on the relations between absolute humidity and other weather variables and influenza outcomes in human populations. In the present study, the authors helped fill this gap by analyzing longitudinal weather and influenza mortality data, observed every month between January 1973 and December 2002, for each of 359 urban US counties. A flexible regression model was used to simultaneously explore fully nonlinear relations between absolute humidity and influenza outcomes and temperature and influenza outcomes. Results indicated that absolute humidity was an especially critical determinant of observed human influenza mortality, even after controlling for temperature. There were important nonlinear relations; humidity levels below approximately 6 g of water vapor per kilogram of air were associated with increases in influenza mortality. Model predictions suggested that approximately half of the average seasonal differences in US influenza mortality can be explained by seasonal differences in absolute humidity alone. Temperature modestly influenced influenza mortality as well, although results were less robust.
Climate Change, Humidity, and Mortality in the United States
Journal of Environmental Economics and Management | 2012 | 63(1): 19-34.
This paper estimates the effects of humidity and temperature on mortality rates in the United States (c. 1973–2002) in order to provide an insight into the potential health impacts of climate change. I find that humidity, like temperature, is an important determinant of mortality. Coupled with Hadley CM3 climate-change predictions, I project that mortality rates are likely to change little on the aggregate for the United States. However, distributional impacts matter: mortality rates are likely to decline in cold and dry areas, but increase in hot and humid areas. Further, accounting for humidity has important implications for evaluating these distributional effects.