Surveillance for molecular and biological properties of HIV strains

The rate of spread of HIV pandemic requires study of the genetic variability of the infectious agent. This study allow us to optimize epidemiological investigations and improve the quality of surveillance. The regional features of the HIV epidemic were studied taking into account the genetic characteristics of the pathogen. We examined 468 sample of biological material (patients with HIV infection blood from 15 subjects of Southern and North Caucasian Federal Districts) from 2014 to 2019. The nucleotide sequences were determined with the ABIPRISM 3500 sequencer, Applied BioSystems (USA). DEONA v1.2.3 (MAG, Russia) software was used to assemble the nucleotide sequences. HIV-1 subtypes were determined using the on-line resources Comet HIV-1 v2.0 and the Stanford University database. We established, that the A1 subtype of HIV-1 still dominates in the Southern and North Caucasian Federal Districts (80.1% of all new strains researched in the laboratory). Subtype B was much less common(6.9%). Since 2009, isolated detection cases of subtype G (3.6%) have been found, but all strains identified at this time had no epidemiological connection with nosocomial outbreaks in southern Russia in the 90s of the 20th century. Also, the recombinant forms of CRF02_AG, CRF03_AB, which previously had a predominant distribution in West Africa, Southeast and Central Asia there, were detected. In 2010, a recombinant subtype, CRF63_02A1 (6.5%), has been registered in the south of Russia. Such regions as Krasnodar Krai, Rostov Oblast and Volgograd Oblast have the greatest variety of HIV-1 variants. It is proven that the majority of carriers of these subtypes of the HIV-1 strain moved to the south of Russia from the Siberia, the Urals and the Kaliningrad region. The study and monitoring of molecular and biological properties of circulating virus strains make it possible to identify the main chains of introduction and spread of the pathogen to different territories, both within the country and in the global migration process.