HIV behind bars: human immunodeficiency virus cluster analysis and drug resistance in a reference correctional unit from southern Brazil

Abstract

People deprived of liberty in prisons are at higher risk of infection by the human immunodeficiency virus (HIV) due to their increased exposure through intravenous drug use, unprotected sexual activity, tattooing in prison and blood exposure in fights and rebellions. Yet, the contribution of intramural HIV transmission to the epidemic is scarcely known, especially in low- and middle-income settings. In this study, we surveyed 1,667 inmates incarcerated at Presídio Central de Porto Alegre, located in southern Brazil, for HIV infection and molecular characterization. The HIV seroprevalence was 6.6% (110/1,667). Further analyses were carried out on 40 HIV-seropositive inmates to assess HIV transmission clusters and drug resistance within the facility with the use of molecular and phylogenetic techniques. The molecular epidemiology of HIV-1 subtypes observed was similar to the one reported for the general population in southern Brazil, with the predominance of HIV-1 subtypes C, B, CRF31_BC and unique BC recombinants. In particular, the high rate (24%) of URF_BC found here may reflect multiple exposures of the population investigated to HIV infection. We failed to find HIV-infected inmates sharing transmission clusters with each other. Importantly, the analysis of HIV-1 pol genomic fragments evidenced high rates of HIV primary and secondary (acquired) drug resistance and an alarming proportion of virologic failure among patients under treatment, unveiling suboptimal access to antiretroviral therapy (ARV), low ARV adherence and dissemination of drug resistant HIV strains in primary infections. Our results call for immediate actions of public authority to implement preventive measures, serological screening and, for HIV-seropositive subjects, clinical and treatment follow-up in order to control HIV infection and limit the spread of drug resistance strains in Brazilian prisons.

Figure 1. Phylogenetic analysis of HIV intraprison transmission clusters.

A, Maximum likelihood analysis between inmate (P) and local control (LC) HIV-1 subtype C sequences. P sequences generated in this study are shown in bold face. The clustering of inmate sequences P44 and P46 with high bootstrap support is boxed in red, suggesting a transmission link. In addition to LC sequences from Porto Alegre, reference HIV-1C sequences retrieved from GenBank are included. An HIV-1B reference sequence was used to root the tree. The aligned region corresponded to 730 bp. Only aLRT values greater than 0.85 are shown. B, Same as in A, except for the inclusion of ten additional sequences retrieved from the GenBank database which corresponded to the top-ten matched HIV sequences using the P44 and P46 sequences as query in a Blast analysis. The red line denotes the split between P44 and P46.