Predominance of CRF63_02A1 and multiple patterns of unique recombinant forms of CRF63_A1 among individuals with newly diagnosed HIV-1 infection in Kemerovo Oblast, Russia.

Kemerovo Oblast (KO) has had the highest rate of HIV spread in Russia since 2011. The aim of this work was to study the genetic variation of HIV-1 in Kemerovo Oblast. Blood was sampled from a total of 91 HIV-positive antiretroviral-therapy-naïve individuals in 2013 (38) and 2015 (53). HIV-1 subtypes, pol gene drug resistance mutations, and viral tropism were analyzed. In 2013-2015, the prevalence of HIV-1 subtype A decreased in KO from 60.5 to 7.5 %. The samples collected in 2015 from the patients with newly diagnosed HIV demonstrate the current dominance of HIV-1 CRF63_02A1 (71.7 %) and HIV-1 URF63_A1 (20.8 %), their parental viruses being CRF63_02A1 and subtype A. The initially predominant genetic variant, HIV-1 subtype A, was replaced in KO. An unusually high incidence of HIV-1 unique recombinant forms is probably the result of HIV-1 CRF63_02A1 introduction in the group of injection drug users with the initial HIV-1 subtype A infection and the practice of risky behavior that promotes reinfection. HIV-1 CRF63_02A1, which recently emerged in Siberia, and its recombinant forms have an ever-increasing impact on the current HIV epidemic in Russia, making urgent the need for in-depth study of this HIV-1 genetic variant.