Dengue in Buenos Aires: an analysis of the factors contributing to increased incidence of dengue fever in urban environments

Dengue is a neglected infectious disease transmitted by the Aedes aegypti mosquito, which primarily inhabits urban tropical areas. Dengue is endemic in more than 100 countries; over the last 50 years, there has been a 4.6 fold increase in dengue incidence, spreading to a larger geographical region. In Argentina, there is low dengue incidence, and cases are concentrated in the northern tropical regions. However, in 2009, the capital city of Buenos Aires, located in a temperate region, experienced a historic outbreak of autochthonous and imported dengue. This study approaches the socio-demographic factors possibly associated with this outbreak and the spatial relationship between these factors and dengue fever in Buenos Aires. \ud \ud Fieldwork was done in Buenos Aires where I conducted interviews with dengue experts, and collected dengue and socio-demographic data. Dengue cases in 2009 were analyzed by hospital area of the city in relation to 2010 census data on population density, place of birth, proportion of the population with unsatisfied basic needs, and sanitary installations in homes. Odds ratios and case level analyses were done between dengue and these risk factors. GIS was used to determine spatial distribution of risk factors and dengue in Buenos Aires.\ud \ud In interviews, dengue experts in Buenos Aires argued immigration and access to sanitation contributed to the spike in dengue incidence and high concentration of cases in the southern periphery of the city during the 2009 outbreak. High immigrant populations were thought to be associated with spatial disparities of dengue and increased incidence in these areas. Yet, contrary to interview findings, odds ratios fail to show correlation between areas with increased immigration and high dengue by hospital area. Findings suggest trends of positive correlation between areas with high dengue and high poverty. Dengue appears to be higher in areas with low population density as well. \u