[Study of human immunodeficiency virus transmission chains in Andalusia: analysis from baseline antiretroviral resistance sequences]

Abstract

Introduction and objective: Protease and reverse transcriptase HIV-1 sequences provide useful information for patient clinical management, as well as information on resistance to antiretrovirals. The aim of this study is to evaluate transmission events, transmitted drug resistance, and to georeference subtypes among newly diagnosed patients referred to our center.

Methods: A study was conducted on 693 patients diagnosed between 2005 and 2012 in Southern Spain. Protease and reverse transcriptase sequences were obtained for resistance to cART analysis with Trugene(®) HIV Genotyping Kit (Siemens, NAD). MEGA 5.2, Neighbor-Joining, ArcGIS and REGA were used for subsequent analysis.

Results: The results showed 298 patients clustered into 77 different transmission events. Most of the clusters were formed by pairs (n=49), of men having sex with men (n=26), Spanish (n=37), and below 45 years of age (73.5%). Urban areas from Granada, and the coastal areas of Almeria and Granada showed the greatest subtype heterogeneity. Five clusters were formed by more than 10 patients, and 15 clusters had transmitted drug resistance.

Conclusions: The study data demonstrate how the phylogenetic characterization of transmission clusters is a powerful tool to monitor the spread of HIV, and may contribute to design correct preventive measures to minimize it.

Keywords: Cluster; Filogenia; Filogeografía; Human immunodeficiency virus; Phylogeny; Phylogeography; Virus de la inmunodeficiencia humana.