HIV type 1 genetic diversity in Silesia, Poland: a retrospective analysis

Molecular epidemiology of recent HIV-1 infections in southern Poland

The genetic diversity of human immunodeficiency virus type 1 (HIV-1) offers an opportunity to track the development of the epidemic across different populations. Viral pol gene fragments from 55 individuals of Polish origin with recent HIV-1 infection identified in 2008-2010 in four Polish cities were analyzed. Viral sequences were compared with sequences from 100 individuals (reference group) infected before 2004. Viral spread among groups with different HIV transmission categories was compared using a phylogenetic approach. The majority of sequences from individuals with recent infection were subtype B (93%) within which four transmission clusters (18% of samples) were detected. Samples from men infected through sex between men and from persons infected through injecting drugs were broadly separated (P < 0.0001), while samples from individuals infected by heterosexual contacts were dispersed uniformly within phylogenetic tree (P = 0.244) inferred from viral sequences derived from individuals infected recently and the reference group. The percentage of samples from persons infected by heterosexual contacts which clustered with samples from men infected through sex between men was not significantly higher for those with recent infection (47%), compared to the reference group (36%). In conclusion, men infected by sex between men and individuals infected through injecting drugs appear to form separate HIV transmission networks in Poland. The recent spread of HIV-1 among persons infected with subtype B by heterosexual contacts appears to be linked to both these groups.

Circulating trends of non-B HIV type 1 subtypes among Kenyan individuals

As the AIDS pandemic progresses, an increasingly broad range of genetic diversity continues to be reported within the main (M) group of HIV-1 viruses with viral subtype predominating in specific geographic areas. To determine the genetic diversity of HIV-1 subtypes among Kenyan individuals, the env-C2-V3 gene was successfully sequenced in samples from 176 patients. Analysis of the sequences showed that a majority of them belonged to subtype A1: 73.9% (130/176), followed by C: 10.8% (19/176), D: 10.2% (18/176), and 0.6% (1/176) for G and A2 as pure subtypes while the rest were recombinants of A1/U: 2.3% (4/176) and 0.6% (1/176) each for D/U, A/C/U, and AC. Similar to previous studies conducted in other parts of Kenya, HIV-1 subtype A1 still remains the most predominant subtype while subtype C continues to show an increasing prevalence. Continued surveillance of circulating subtypes of HIV-1 in Kenya is important in determining the evolution of the HIV/AIDS epidemic in Kenya.