Spatial Clustering of HIV Prevalence in Atlanta, Georgia and Population Characteristics Associated with Case Concentrations

Abstract

We assessed prevalent HIV cases in Atlanta to examine case distribution trends and population characteristics at the census tract level that may be associated with clustering effects. We calculated cluster characteristics (area and internal HIV prevalence) via Kuldorff's spatial scan method. Subsequent logistic regression analyses were performed to analyze sociodemographics associated with inclusion in a cluster. Organizations offering voluntary HIV testing and counseling services were identified and we assessed average travel time to access these services. One large cluster centralized in downtown Atlanta was identified that contains 60% of prevalent HIV cases. The prevalence rate within the cluster was 1.34% compared to 0.32% outside the cluster. Clustered tracts were associated with higher levels of poverty (OR=1.19), lower density of multi-racial residents (OR=1.85), injection drug use (OR=1.99), men having sex with men (OR=3.01), and men having sex with men and IV drug use (OR=1.6). Forty-two percent (N=11) of identified HIV service providers in Atlanta are located in the cluster with an average travel time of 13 minutes via car to access these services (SD=9.24). The HIV epidemic in Atlanta is concentrated in one large cluster characterized by poverty, men who have sex with men (MSM), and IV drug usage. Prevention efforts targeted to the population living in this area as well as efforts to address the specific needs of these populations may be most beneficial in curtailing the epidemic within the identified cluster.

The acquired immunodeficiency syndrome in the State of Rio de Janeiro, Brazil: a spatio-temporal analysis of cases reported in the period 2001-2010

“…The high AIDS incidence, which was observed in the metropolitan region of the State of Rio de Janeiro, can also be seen in other metropolitan areas, such as in some populated urban regions of South Africa (Manda et al, 2012), the metropolitan area of Atlanta (Hixson, 2011) and another 11 large urban areas in the United States of America (Hall et al, 2010). In 2011, the AIDS incidence in Brazil was 20.2 cases per 100,000.…”

“…The Metropolitan Rio de Janeiro area has hundreds of low-income communities and some studies indicate that higher AIDS incidence tend to occur in poorer neighbourhoods (Greco and Simão, 2007;Hixson et al, 2011;Shacham et al, 2013;da Silva Pires Araujo et al, 2014). It has been suggested that poverty may increase the vulnerability to HIV infection since it hinders access to information, preventive measures and healthcare.…”

“…Spatial analysis can also assist decision-making for disease intervention and has been employed for surveillance purposes in the field of public health. Several studies have focused on investigating the geographical distribution, spatial clusters and spread of AIDS describing the dynamic trends using spatio-temporal analysis or statistical methods (Berkley et al, 1989;Lam et al, 1996;Hixson et al, 2011;Peng et al, 2011;Manda et al, 2012). Spatial clustering analysis provides useful information on where to intervene and can also contribute to more effective intervention.…”

Geospatial mapping to identify feasible HIV prevention and treatment strategies that target specific settings

“…In their study, the authors describe a geostatistical framework for designing a novel treatment as prevention (TasP) for HIV elimination strategy (2). They make the argument that reaching the UNAIDS goals of 90-90-90 (diagnosed-treated-virologically suppressed) may be quite difficult in some rural communities.…”

“…We have previously applied geospatial clustering techniques to analyze the local HIV prevalence in Atlanta, Georgia, USA and identified that there are areas within urban areas that could be characterized as having a generalized HIV epidemic according to the World Health Organization definition at the time (2). Given the severity of the HIV epidemic in the Southern US, we used geospatial techniques to demonstrate the feasibility of reaching urban "hidden populations" who were highly susceptible to HIV in order to meet HIV prevention and treatment priorities (3).…”