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

Abstract

Surveillance on the HIV molecular variability, risk of drug resistance transmission and evolution of novel viral variants among blood donors remains an understudied aspect of hemovigilance. This nationwide study analyses patterns of HIV diversity and transmitted resistance mutations. Study included 185 samples from the first time and repeat blood donors with HIV infection identified by molecular assay. HIV protease, reverse transcriptase and integrase were sequenced using population methods. Drug resistance mutation (DRM) patterns were analyzed based on the Stanford Interpretation Algorithm and standardized lists of transmitted mutations. Phylogeny was used to investigate subtyping, clustering and recombination patterns. HIV-1 subtype B (89.2%) followed by subtype A6 (7.6%) were predominant, while in three (1.6%) cases, novel recombinant B/A6 variants were identified. Non-B variants were more common among repeat donors (14.5%) compared to the first time ones (1.8%), p = 0.011, with higher frequency (9.9%) of A6 variant in the repeat donor group, p = 0.04. Major NRTI DRMs were observed in 3.8%, NNRTI and PI in 0.6% and INSTI 1.1% of cases. Additionally, E157Q polymorphism was observed in 9.8% and L74I in 11.5% of integrase sequences. Transmission of drug resistance among blood donors remains infrequent. Subtype patters increase in complexity with emergence of novel intersubtype A6B recombinants.

Figure 1

Maximum likelihood tree showing the subtype A identification with the reference sequences from HIV sequence compendium supplemented with A1 and A6 sequences from GenBank. A1 variant is colored in blue, A6 in green.

Figure 2

Three unique recombinant form genome maps and the separate phylogenetic ML trees with the corresponding partial protease/reverse transcriptase and integrase sequences confirming the subtype assignment. For the tree reconstruction a dataset obtained from HIV sequence compendium 2018 was used. Multiple branches for the same subtype were collapsed. A. sequence 2886 acquired in the city of Warsaw, B. sequence 2495 acquired in the city of Krakow, C. sequence 5474 acquired in the city of Warsaw.

Figure 3

Frequency of major and transmitted drug resistance mutations (red) and variants associated with decreased drug susceptibility (Stanford HIV DB, score ≥ 10, green) for nucl(t)eoside reverse transcriptase (a), non-nucleoside reverse transcriptase (b), protease (c) and integrase (d) inhibitors. As non-nucleoside reverse transcriptase E138A mutation is not included in the tDRM list, but is associated with significant reduction of susceptibility to rilpivirine, it was marked in violet.

Figure 3

Frequency of major and transmitted drug resistance mutations (red) and variants associated with decreased drug susceptibility (Stanford HIV DB, score ≥ 10, green) for nucl(t)eoside reverse transcriptase (a), non-nucleoside reverse transcriptase (b), protease (c) and integrase (d) inhibitors. As non-nucleoside reverse transcriptase E138A mutation is not included in the tDRM list, but is associated with significant reduction of susceptibility to rilpivirine, it was marked in violet.

Figure 4

MCMC tree showing the relationship between clusters and mutations and city of diagnosis for subtype B with the inclusion of the protease/reverse transcriptase region of the of the subtype B/A6 recombinant (tree branches marked in red). Transmitted drug resistance substitutions were color-coded and included at the external taxonomical units: brown—resistance against nucleoside reverse transcriptase inhibitors, red—resistance against non-nucleoside reverse transcriptase inhibitors, blue – resistance against protease inhibitors, green—resistance against integrase inhibitors . Clusters have been indicated on the tree with magenta highlight using < 1.5% genetic distance and > 90% branch support.