142nd APHA Annual Meeting and Exposition

Annual Meeting Recordings are now available for purchase

Social and Environmental Factors of Dengue Fever in the Sonoran Desert of Mexico, 2006-2011

142nd APHA Annual Meeting and Exposition (November 15 - November 19, 2014): http://www.apha.org/events-and-meetings/annual
Tuesday, November 18, 2014 : 3:15 PM - 3:30 PM

Pablo Alejandro Reyes Castro, PhD Candidate , Mel and Enid Zuckerman College of Public Health, University of Arizona, Tucson, AZ
Kacey Ernst, PhD , Mel and Enid Zuckerman College of Public Health, University of Arizona, Tucson, AZ
Background: Dengue fever is currently endemic in the Mexican Sonoran Desert but transmission risk is not the same across the region. The aim of this study was to determine social and environmental factors associated with varying levels of dengue incidence at the locality level in Sonora, MX between 2006 and 2011. Understanding factors associated with risk under current conditions can inform the potential for expansion of dengue into other areas.

Methodology: Incidence of dengue was calculated for each locality (N=1,158), census and remotely sensed information, Zero-inflated negative binomial modelling (ZINB) was then used in order to simultaneously assess: 1) the association of dengue incidence with social and environmental factors; and 2) the probability that factors such as population size and distance to the main highway may lead to exessive zeros that are related to barriers of disease surveillance and thus the accurate reporting of dengue cases.

Results: Incidence varied over the study period and was higher in southern and western parts of the state. According to the best model, dengue incidence increases 31.4% (IRR=1.314, 95% CI: 1.204, 1.435) per 1 inch of increment in cumulative rainfall and 56.8% (IRR=1.568, 95% CI: 1.255, 1.959) per 1 C° increment in average maximum temperature. Incidence is positively associated with percent of population with no basic education (IRR=1.038, 95% CI: 1.012, 1.064) and log-transformed population size (IRR=1.255, 95% CI: 1.049, 1.503). There is a positive association between the probability of excessive zeros and the distance to the highway (OR=1.033, 95% CI: 1.016, 1.051) and a negative association with log-transformed population size (OR=0.368, 95% CI: 0.212, 0.639).

Discussion: Dengue incidence was associated with higher levels of rainfall, vapor pressure and temperature, and social factors related to urbanization and lack of education. However, potential problems of underreporting could be present in rural localities with higher distance to the land transportation infrastructure.  Further exploration of the accuracy of the surveillance system in place is warranted, particularly in localities that share factors associated with dengue risk but have no reported transmission.

Learning Areas:

Environmental health sciences
Protection of the public in relation to communicable diseases including prevention or control
Public health or related research

Learning Objectives:
Assess the association of disease surveillance data with demographic, infrastructure and climate data. Identify potential problems of disease underreporting related to geographical location and demographic characteristics.

Keyword(s): Epidemiology, Environmental Health

Presenting author's disclosure statement:

Qualified on the content I am responsible for because: Currently I'm a PhD candidate in Epidemiology. I work as research assistant in the Med and Enid Zuckerman College of Public Health, at The University of Arizona, in projects related to the Aedes Aegypti mosquito, the dengue incidence distribution, and the association with social and environmental factors in the US-Mexico border region.
Any relevant financial relationships? No

I agree to comply with the American Public Health Association Conflict of Interest and Commercial Support Guidelines, and to disclose to the participants any off-label or experimental uses of a commercial product or service discussed in my presentation.

Back to: 4318.0: Environmental Epidemiology