HTLV-I/II and blood donors: determinants associated with seropositivity in a low risk population

Abstract

ObjectiveBlood donors in Brazil have been routinely screened for HTLV-I/II since 1993. A study was performed to estimate the prevalence of HTLV-I/II infection in a low risk population and to better understand determinants associated with seropositivity. Methods HTLV-I/II seropositive (n=135), indeterminate (n=167) and seronegative blood donors (n=116) were enrolled in an open prevalence prospective cohort study. A crosssectional epidemiological study of positive, indeterminate and seronegative HTLV-I/II subjects was conducted to assess behavioral and environmental risk factors for seropositivity. HTLV-I/II serological status was confirmed using enzyme-linked immunosorbent assay (EIA) and Western blot (WB). ResultsThe three groups were not homogeneous. HTLV-I/II seropositivity was associated to past blood transfusion and years of schooling, a marker of socioeconomic status, and use of non-intravenous illegal drugs. ConclusionsThe study results reinforce the importance of continuous monitoring and improvement of blood donor selection process. Resumo Objetivo

Definition of a diagnostic routine in individuals with inconclusive serology for chagas disease

“…This is also observed in other Brazilian and South American studies with samples portraying similar characteristics [5,18]. In Brazil, studies show that 62% to 97% of donors are males [22][23][24][25][26][27][28]. Also, the mean age of G2 and G3 individuals was similar to that of blood donation candidates found to be serologically positive for chagasic infection [29].…”

A New and Frequent Human T-Cell Leukemia Virus Indeterminate Western Blot Pattern: Epidemiological Determinants and PCR Results in Central African Inhabitants

“…Such HTLV indeterminate WB patterns have been reported, for the last 20 years, by several authors and are found mainly, and their signification studied, in tropical areas, such as Central Africa and Southeast Asia (24,28,31,41,47,54). However, they have also been reported in other areas, such as European countries (68), the United States (11,51,73), the Caribbean area (17,57), Central and South America (Brazil, Argentina) (6,35,44,50,61), and more recently the Middle East (74). Most of the studies concern blood donors (10,11,16,63) or epidemiological work in the general population (43) but also organ donors for transplantation (22,36), lactariums (19,58,70), and neurological patients (1,73).…”

“…Moreover, research of integrated provirus, in the DNA from peripheral blood cells, could be done by qualitative and/or quantitative PCR (2,4,8,68). Despite some improvements in the WB assays specificity during the last two decades, indeterminate serological patterns are frequent following WB analysis and represent a major concern for routine screening in blood banks in Europe, the Americas, and Africa (7,10,11,16,20,40,61,63). It is also an important issue for comparative analysis between epidemiological studies performed in areas with low and high endemicity, especially in intertropical areas.…”

Human T-lymphotropic virus 1aA circulation and risk factors for sexually transmitted infections in an Amazon geographic area with lowest human development index (Marajó Island, Northern Brazil)

“…However, the 16.5% of the population who were illiterate cannot be ignored because a low level of education is a risk factor for infection with HTLV [34]. These data are useful for the development of local public policies that take into consideration the characteristics and demands of the target population.…”