Transmission patterns of HIV-1 non-R5 strains in Poland

Abstract

HIV-1 env sequencing enables predictions of viral coreceptor tropism and phylogenetic investigations of transmission events. The aim of the study was to estimate the contribution of non-R5 strains to the viral spread in Poland. Partial proviral env sequences were retrieved from baseline blood samples of patients with newly diagnosed HIV-1 infection between 2008–2014, including 46 patients with recent HIV-1 infection (RHI), and 246 individuals with long-term infection (LTHI). These sequences were subjected to the genotypic coreceptor tropism predictions and phylogenetic analyses to identify transmission clusters. Overall, 27 clusters with 57 sequences (19.5%) were detected, including 15 sequences (26.3%) from patients with RHI. The proportion of non-R5 strains among all study participants was 23.3% (68/292), and was comparable between patients with RHI and LTHI (11/46, 23.9% vs 57/246, 23.2%; p = 1.000). All 11 patients with non-R5 strains and RHI were men having sex with men (MSM). Among these patients, 4 had viral sequences grouped within phylogenetic cluster with another sequence of non-R5 strain obtained from patient with LTHI, indicating potential acquisition of non-R5 HIV-1 for at least 4/46 (8.7%) patients with RHI. We were unable to confirm the contribution of patients with RHI to the forward transmission of non-R5 strains, but a relatively high proportion of non-R5 strains among them deserves attention due to the limited susceptibility to CCR5 antagonists.

Transmitted HIV drug resistance and subtype patterns among blood donors in Poland

“…Among treatment naïve cases transmitted drug resistance mutations (DRM) were observed in ~ 9% of cases in the national wide studies (5.8% for nucleoside reverse transcriptase, 1.2% for non-nucleoside reverse transcriptase, and 2.0% for protease mutations) and up to ~ 12% in local cohorts with no transmitted major integrase mutations observed so far 14 – 16 . Additionally, frequency of transmission clusters ranges from 20–30% which indicates high likelihood of HIV epidemics expansion in the future 17 , 18 .…”