Community viral load of HIV in Brazil, 2007 - 2011: potential impact of highly active antiretroviral therapy (HAART) in reducing new infections.

Objectives:: To estimate the human immunodeficiency virus (HIV) viral load in the Brazilian population and to assess the potential impact of highly active antiretroviral therapy (HAART) in reducing new infections to build evidences and to gather information to support health policies.

Methods:: Spatial analysis and modeling tools were used to describe the existing patterns of the viral load density, using the Kernel method. Data on viral load and treatment were retrieved from the databases Laboratory Tests Control System (SISCEL), which contains information on the individual's history of viral load, and Medication Logistics Control System (SICLOM), which controls the dispensing of drugs used for antiretroviral therapy.

Results:: It was observed that the community viral load (CVL) decreased progressively from 2007 to 2011, accompanied by a decrease of more than 32% in the mean CVL (CVLM) - 22,900 copies/mL in 2007 versus 15,418 copies/mL in 2011. During this period, there was a reduction of CVLM in all regions of Brazil, although North and Northeast showed, respectively, CVLM 1.7 and 1.5 times higher than that in the Southeast region. A comparison between the individuals who underwent and who did not undergo HAART showed an increase of up to 3.9 times in 2011 in the viral load among those who did not undergo the therapy.

Conclusion:: The approach presented in this study indicates the existence of clusters with high concentrations. The use of Kernel in the identification of clusters proved to be a good tool for exploratory analysis, enabling the risk identification in certain geographic areas without the usual political and administrative divisions.