Prevalência global e em Goiás das infecções pelos vírus linfotrópicos T humanos 1 e 2 em imigrantes e refugiados

Abstract

Introduction: The international migration of endemic populations for human Tlymphotropic virus 1 and 2 (HTLV-1 and 2) can play a significant role in introducing these viruses in non-endemic territories. Objectives: To estimate the seroprevalence of HTLV-1/2 infection among immigrants and refugees in Goiás State and the seropositivity rates for HTLV-1 and HTLV-2, analyze factors related to HTLV-1/2 infection, and describe the risk behaviors/practices reported by HTLV-1 and HTLV-2 seropositive individuals. In addition, we estimate the global prevalence of HTLV-1 and HTLV-2 infections among immigrants and refugees, and also identify potential variables as sources of heterogeneity between the studies analyzed. Methods: Article 1 - Crosssectional study with 537 international migrants in the State of Goiás. Participants were interviewed about sociodemographic data and risk behaviors for HTLV-1/2 infection between July 2019 and May 2021, and serum samples from 528 migrants were screened using an enzyme-linked immunosorbent assay (ELISA). Anti-HTLV-1/2 reactive samples were submitted for confirmation by a line immunoassay (LIA). Fisher's exact test was used for statistical analysis. Article 2 – Systematic review and meta-analysis of prevalence studies on HTLV-1 and/or HTLV-2 infections among immigrants and refugees worldwide. The databases PubMed/MEDLINE, Scopus, EMBASE, Web of Science and Virtual Health Library (VHL) were searched from the inception of studies published until January 06, 2023. A meta-analysis using a generalized mixed linear model with random effect was performed for HTLV-1 and HTLV-2. Subgroup analyses were used to evaluate the effect of decade of study, sample size, confirmatory methods, region of study, risk group, and region of origin on prevalence. Results: Article 1 - The majority of participants were Venezuelan (47.9%) and Haitian (39.7%); 50.1% were immigrants, 49% refugees and five were Brazilian children (0.9%) born to Haitian immigrant parents. The overall prevalence of anti-HTLV-1/2 was 0.95% (95% CI: 0.31- 2.28), HTLV-1 (0.19%) and HTLV-2 (0.76%). All seropositive individuals (n = 5) were refugees from Venezuela, resulting in a rate of 2.26% for anti-HTLV-1/2, HTLV-1 (0.45%) and HTLV-2 (1.81%) among Venezuelan refugees. Unprotected sexual intercourse and having more than one sexual partner (≥2) in the previous 12 months were factors related to HTLV-1/2 seropositivity among Venezuelans. Reporting of having been breastfed for more than six months and unprotected sex with one or two partners were risk characteristics observed in seropositive individuals. Article 2 – Of a total of 381 records initially identified, 21 studies were included. The global prevalence of HTLV-1 and HTLV-2 infections was 1.28% (95% CI: 0.58-2.81) and 0.11% (95% CI: 0.04-0.33), respectively. HTLV-1 prevalence differed significantly by region of origin, with the highest prevalence among those from the Western Pacific Region (7.27%; 95% CI: 2.94- 16.83). In the subgroup analysis, significant differences were also observed between the estimates of HTLV-1 infection considering the decade of study, sample size, and regionof study. For HTLV-2, significant differences were noted in relation to sample size, confirmatory methods, and risk group. Conclusions: The results show that the seroprevalence of HTLV-1/2 among international migrants in Goias State is low; however, the seropositivity for HTLV-1 and HTLV-2 indicates the circulation of these viruses in Venezuelan refugees; also pointing out the importance of sexual transmission of HTLV-1/2 in addition to the report of breastfeeding for more than six months by seropositive individuals. The systematic review and meta-analysis reveal that, despite the heterogeneity observed, the HTLV-1 prevalence among immigrants and refugees is higher than HTLV-2. The high prevalence of HTLV-1 found, particularly among those from the Western Pacific Region, suggests that targeted serological screening of international migrants from HTLV-1 endemic regions could be a significant public health intervention for this infection control in immigrant and refugee-receiving non-endemic countries. Relevance and Impact: This study characterizes immigrants and refugees as vulnerable to HTLV-1/2 infection, highlighting the importance of developing public health policies focusing on prevention and control of this infection in international migrants.