Human T-Lymphotropic Virus-1/2 Infection in Central Brazil Prisons: A Multicenter Study

Abstract

Human T-lymphotropic virus (HTLV) infection is endemic in some group populations. Prisoners are at high risk of acquiring HTLV infection mainly due to the environment of closed penal institutions, socioeconomic conditions, and risk behaviors. This study aimed to investigate the prevalence, the occurrence of new cases of HTLV infection after a 1-year follow-up, and circulating subtypes of HTLV-1 among prisoners from twelve closed prisons in Mato Grosso do Sul state, Central Brazil. A total of 1,507 prisoners were randomly enrolled in the cross-sectional study. Out of the 1,507 participants, 1,000 prisoners, susceptible to HTLV infection, were included in the prospective cohort study. In the cross-sectional study, serological evidence of HTLV infection was 0.4% (CI 95%: 0.1-0.7), tested for anti-HTLV antibodies by enzyme-linked immunosorbent assay (ELISA). Three samples were positive for HTLV-1, two samples were positive for HTLV-2, and 1 sample was indeterminate by the Western blot method. The presence of HTLV proviral DNA was detected in all positive samples by amplification of the HTLV tax gene through nested-PCR. Phylogenetic analysis showed that HTLV-1 samples belonged to the Cosmopolitan subtype Transcontinental subgroup. From a cohort of 1,000 individuals, no new case of HTLV infection was detected. Although the prevalence rate of HTLV infection found in this study was similar to that observed in the Brazilian general population, the lack of access to preventive interventions and harm reduction measures all contribute to increasing the risk of HTLV transmission and acquisition among this key and vulnerable population.

Spread of Human T-Lymphotropic Virus 1 and 2 Among Relatives of People Who Use Illicit Drugs in Northern Brazil

“…The samples in this study can be identified by traces in red (PWUDs) and blue (their relatives). Oliveira-Filho et al, 2019a;de Souza et al, 2020;Ishak et al, 2020b), other Brazilian regions (Renner et al, 2006;Novoa et al, 2007;de Almeida Rego et al, 2010;de Oliveira et al, 2012;Magri et al, 2012;Pessôa et al, 2014;Bandeira et al, 2015Bandeira et al, , 2022Castro et al, 2018;Ribeiro et al, 2018), and in South American countries (Leon-Ponte et al, 1996;Miura et al, 1997;Talarmin et al, 1999;Berini et al, 2013;Abreu et al, 2022). However, the same viral subtype detected in 15 PWUDs was detected in their family members.…”

“…High rates of HTLV-1 and HTLV-2 infections have been recorded in Brazil, mainly in the states of Bahia, Maranhão, and Pará (Catalan-Soares et al, 2005). HTLV-1a, HTLV-2b, and HTLV-2c have shown high frequencies in studies conducted in key populations in Brazil, such as prisoners, female sex workers (FSW), people who use illicit drugs (PWUDs), and men who have sex with men (MSM) (Castro et al, 2018;Oliveira-Filho et al, 2019a;de Souza et al, 2020;Bandeira et al, 2022). Recently, two epidemiological studies conducted with PWUDs, and indigenous refugees recorded the movement of people infected with HTLV-1 (1aB) and between Brazilian states and countries located in the Amazon region and evidenced the spread of these retroviruses in South America (Oliveira-Filho et al, 2019a;Abreu et al, 2022).…”