HCV Genotypes, Characterization of Mutations Conferring Drug Resistance to Protease Inhibitors, and Risk Factors among Blood Donors in São Paulo, Brazil

Background: Hepatitis C virus (HCV) infection is a global health problem estimated to affect almost 200 million people worldwide. the aim of this study is to analyze the subtypes and existence of variants resistant to protease inhibitors and their association with potential HCV risk factors among blood donors in Brazil.Methods: Repeat anti-HCV reactive blood donors are systematically asked to return for retest, notification, and counseling in which they are interviewed for risk factors for transfusion-transmitted diseases. We analyzed 202 donors who returned for counseling from 2007 to 2010 and presented enzyme immunoassay-and immunoblot-reactive results. the HCV genotypes and resistance mutation analyses were determined by the direct sequencing of the NS5b and NS3 regions, respectively. the HCV viral load was determined using an in-house real-time PCR assay targeting the 5'-NCR.Results: HCV subtypes 1b, 1a, and 3a were found in 45.5%, 32.0%, and 18.0% of the donors, respectively. the mean viral load of genotype 1 was significantly higher than that of the genotype 3 isolates. Subtype 1a was more frequent among young donors and 3a was more frequent among older donors. Protease inhibitor-resistant variants were detected in 12.8% of the sequenced samples belonging to genotype 1, and a higher frequency was observed among subtype 1a (20%) in comparison to 1b (8%). There was no difference in the prevalence of HCV risk factors among the genotypes or drug-resistant variants.Conclusions: We found a predominance of subtype 1b, with an increase in the frequency of subtype 1a, in young subjects. Mutations conferring resistance to NS3 inhibitors were frequent in treatment-naive blood donors, particularly those infected with subtype 1a. These variants were detected in the major viral population of HCV quasispecies, have replicative capacities comparable to nonresistant strains, and could be important for predicting the response to antiviral triple therapy.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundacao Pro-Sangue/Hemocentro de São PauloFundacao Prosangue Hemoctr São Paulo, São Paulo, BrazilUniversidade Federal de São Paulo, Infect Dis Div DIPA, São Paulo, BrazilUniv São Paulo, Fac Med, Discipline Med Sci, São Paulo, BrazilHCFMUSP, Dept Pathol, LIM Lab Medice Lab 03, São Paulo, BrazilUniv Sao Joao del Rei, Divinopolis, MG, BrazilUniv São Paulo, Fac Med, Dept Infect Dis, São Paulo, BrazilUniversidade Federal de São Paulo, Infect Dis Div DIPA, São Paulo, BrazilWeb of Scienc

Transfusion-Acquired HIV: History, Evolution of Screening Tests, and Current Challenges of Unreported Antiretroviral Drug Use in Brazil

Prevention of HIV acquisition by blood transfusion from its emergence to the present day is reviewed, and current challenges are delineated. The experience of Fundação Pró-Sangue/Hemocentro de São Paulo, Brazil, is highlighted in the quest for improvements in blood safety and the evolution of increasingly sensitive and specific screening tests. Concerns and establishing stringent criteria in the screening of potential blood donors are emphasized, and the current criteria for identifying and deferring candidates at high risk of acquiring sexually transmitted diseases are summarized. Future challenges relate to the identification of donors with unreported use of antiretroviral drugs for prophylaxis against possible HIV exposure or for treatment of an HIV infection whose viral expression is undetectable by current analyses. There is a need to better understand the motivation of HIV-exposed donors and to educate them about the risk of transfusion-mediated HIV transmission despite having low or undetectable viral loads. In situations in which traditional HIV RNA or antibody detection assays remain negative, more sensitive analyses are needed to identify potential donors at risk for HIV transmission

Programas de control externo de la calidad en serología desarrollados en América Latina con el apoyo de la OPS entre 1997 y 2000

OBJETIVOS: Con el apoyo de la Organización Panamericana de la Salud (OPS), desarrollamos entre 1997 y 2000 cinco programas de control externo de la calidad en serología (PCECS) en los que participaron entre 13 y 21 bancos de sangre de 11 a 16 países de América Latina. El objetivo fue evaluar el desempeño de los bancos de sangre con respecto al tamizaje serológico realizado en donantes de sangre. MÉTODOS: Como herramienta de trabajo utilizamos conjuntos de 24 muestras de sueros anónimos con reactividades variables para los parámetros de uso obligatorio en el tamizaje serológico de donantes de sangre en Brasil. En cada PCECS enviamos un multipanel a cada institución participante para que lo procesara en las mismas condiciones de su rutina de tamizaje. Cada participante recibió la clave del multipanel para autoevaluación, después de haber devuelto los resultados obtenidos en su laboratorio. Se mantuvo siempre la más estricta confidencialidad sobre los resultados obtenidos individualmente. Al terminar de cada programa, el Centro Organizador (Superintendencia de Serología de la Fundação Pró-Sangue/Hemocentro de São Paulo) elaboró un informe final que contenía toda la información obtenida en el programa y que fue enviado a los participantes. RESULTADOS: En el análisis de los cinco PCECS se observó falta de homogeneidad entre los países con respecto a las estrategias y a los parámetros utilizados en el tamizaje de donantes de sangre. Pocos laboratorios practicaron el tamizaje de los virus linfotrópico de células T humanas (HTLV) (17%, 27%, 35%, 39% y 45%, respectivamente y en orden creciente para los cinco PCECS) y de anticuerpos contra el antígeno nuclear del virus de la hepatitis B (anti-HBc) (42%, 27%, 39%, 50% y 60%). También se observaron diferencias importantes en cuanto a las pruebas o combinaciones de pruebas utilizadas, lo cual puede dificultar el estudio comparativo de los tipos de tamizaje. El número total de resultados positivos falsos osciló alrededor del 2%, correspondiendo el mayor valor al tamizaje de anticuerpos contra el virus de la hepatatis C (anti-VHC) (4,6%) y el menor a anti-Trypanosoma cruzi (0,4%). CONCLUSIONES: Los resultados obtenidos en este trabajo demuestran la necesidad de continuar las acciones de la OPS en América Latina para reforzar los procedimientos de tamizaje serológico en bancos de sangre, incluso los PCECS, hasta que se consiga una uniformidad de procedimientos en la Región de las Américas

Evaluation of the concomitant use of two different EIA tests for HIV screening in blood banks

OBJECTIVE: In 1998, the Brazilian Ministry of Health made it mandatory for all blood banks in the country to screen donated blood for human immunodeficiency virus (HIV) concomitantly using two different enzyme immunoassay (EIA) tests. Concerned with the best use of available resources, our objective with this study was to evaluate the usefulness of conducting two EIA screening tests instead of just one. METHODS: We analyzed data from 1999 through 2001 obtained by testing 698 191 units of donated blood using two EIA HIV screening tests concomitantly at the Pro-Blood Foundation/Blood Center of São Paulo (Fundação Pró-Sangue/Hemocentro de São Paulo), which is a major blood center in the city of São Paulo, Brazil. All samples reactive in at least one of the two EIA tests were submitted for confirmation by a Western blot (WB) test, and the persons who had donated those samples were also asked to return and provide a follow-up sample. RESULTS: Out of the 698 191 blood units that were donated, 2 718 of them (0.4%) had to be discarded because they were reactive to at least one of the EIA tests. There were two WB-positive donation samples that were reactive in only one HIV EIA screening test. On their follow-up samples, both donors tested WB-negative. These cases were considered false positive results at screening. Of the 2 718 donors who were asked to return and provide a follow-up sample, 1 576 of them (58%) did so. From these 1 576 persons, we found that there were two individuals who had been reactive to only one of the two EIA screening tests and who had also been negative on the WB at screening but who were fully seroconverted on the follow-up sample. We thus estimated that, in comparison to the use of a single EIA screening test, the use of two EIA screening tests would detect only one extra sample out of 410 700 units of blood. CONCLUSIONS: Our data do not support the use of two different, concomitant EIA screening tests for HIV. The great majority of HIV-positive donors have already seroconverted and will be detected using only a single EIA screening test. Only persons who are going through the process of seroconversion may be missed by using a single EIA test and detected using two EIAs for screening. To screen out these individuals and decrease the residual risk of HIV transmission from the blood donated in our center, the use of other techniques, such as nucleic acid testing (NAT) or a p24 antigen assay, would be more effective

Descarte de bolsas de sangue e prevalência de doenças infecciosas em doadores de sangue da Fundação Pró-Sangue/Hemocentro de São Paulo

OBJETIVO: Analisar a evolução, de 1991 a 2001, do descarte sorológico na Fundação Pró-Sangue/Hemocentro de São Paulo, o maior banco de sangue da América Latina, e verificar a prevalência de doenças infecciosas entre doadores dessa instituição no ano de 2001. MÉTODOS: Foram compilados os dados de descarte sorológico relativos aos anos de 1991 a 2001. Para determinar a prevalência de doenças infecciosas, foram analisadas 9 942 amostras triadas em novembro de 2001, sendo as amostras reativas submetidas a testes confirmatórios. RESULTADOS: Foi encontrada uma diminuição percentual significativa de descarte, de 20% em 1991 para 9% em 2001. A prevalência de doenças infecciosas entre doadores em 2001 foi de 0,04% para vírus da imunodeficiência humana (VIH); 0,21% para vírus da hepatite C (VHC); 0,06% para vírus T-linfotrópico humano (HTLV); para vírus da hepatite B (VHB), as prevalências foram de 0,14% para anti-HBc + HBsAg, 1,68% para anti-HBc + anti-HBs e 1,67% para anti-HBc isolado; 1,10% para sífilis; e 0,14% para doença de Chagas. CONCLUSÃO: A diminuição no descarte e a prevalência de doenças infecciosas entre doadores da Fundação Pró-Sangue/Hemocentro de São Paulo em 2001 refletem o aumento na porcentagem de doadores de repetição nesse banco de sangue

Knowledge, attitudes and motivations among blood donors in Sao Paulo, Brazil

Recruiting safe, volunteer blood donors requires understanding motivations for donating and knowledge and attitudes about HIV. We surveyed 1,600 persons presenting for blood donation at a large blood bank in Sao Paulo, Brazil using a self-administered, structured questionnaire, and classified motivations into three domains as well as categorizing persons by HIV test-seeking behavior. Motivations, in descending order, and their significant associations were: ""altruism``: female gender, volunteer donor and repeat donor status; ""direct appeal``: female gender, repeat donor status and age 21-50 years; ""selfinterest``: male gender, age under 20 years, first-time donor status and lower education. HIV test-seekers were more likely to give incorrect answers regarding HIV risk behavior and blood donation and the ability of antibody testing to detect recent HIV infections. Altruism is the main motivator for blood donation in Brazil; other motivators were associated with specific demographic subgroups. HIV test-seeking might be reduced by educational interventions

Human immunodeficiency virus prevalence, incidence, and residual risk of transmission by transfusions at Retrovirus Epidemiology Donor Study-II blood centers in Brazil

BACKGROUND: In Brazil nationally representative donor data are limited on human immunodeficiency virus (HIV) prevalence, incidence, and residual transfusion risk. The objective of this study was to analyze HIV data obtained over 24 months by the Retrovirus Epidemiology Donor Study-II program in Brazil. STUDY DESIGN AND METHODS: Donations reactive to third-and fourth-generation immunoassays (IAs) were further confirmed by a less-sensitive (LS) IA algorithm and Western blot (WB). Incidence was calculated for first-time (FT) donors using the LS-EIA results and for repeat donors with a model developed to include all donors with a previous negative donation. Residual risk was projected by multiplying composite FT and repeat donor incidence rates by HIV marker-negative infectious window periods. RESULTS: HIV prevalence among FT donors was 92.2/ 105 donations. FT and repeat donor and composite incidences were 38.5 (95% confidence interval [CI], 25.651.4), 22.5 (95% CI, 17.6-28.0), and 27.5 (95% CI, 22.0-33.0) per 100,000 person-years, respectively. Male and community donors had higher prevalence and incidence rates than female and replacement donors. The estimated residual risk of HIV transfusion transmission was 11.3 per 106 donations (95% CI, 8.4-14.2), which could be reduced to 4.2 per 106 donations (95% CI, 3.2-5.2) by use of individual-donation nucleic acid testing (NAT). CONCLUSION: The incidence and residual transfusion risk of HIV infection are relatively high in Brazil. Implementation of NAT will not be sufficient to decrease transmission rates to levels seen in the United States or Europe; therefore, other measures focused on decreasing donations by at-risk individuals are also necessary.NHLBI [HHSN268200417175C]NHLB

Human T-lymphotropic virus type 1 and type 2 seroprevalence, incidence, and residual transfusion risk among blood donors in Brazil during 2007-2009.

Human T-lymphotropic virus type 1/2 (HTLV-1/2) infection is endemic in Brazil but representative donor prevalence and incidence data are lacking. All blood donations (2007-2009) from three blood centers in Brazil were studied. Samples reactive on one HTLV screening test (EIA) were retested with a different EIA; dual EIA reactivity correlated strongly with a confirmatory Western blot. Prevalence, incidence, and residual transfusion risk were calculated. Among 281,760 first-time donors, 363 were positive for HTLV on both EIAs (135 per 10(5), 95% CI 122-150). Prevalence differed considerably by region, from 83 to 222 per 10(5). Overall incidence rate was 3.6/10(5) person-years and residual transfusion risk was 5.0/10(6) per blood unit transfused. The logistic regression model showed significant associations with: age [adjusted odds ratio (aOR)=5.23 for age 50+ vs. <20], female sex (aOR=1.97), black (aOR=2.70 vs. white), and mixed skin colors (aOR=1.78 vs. white), and inversely with education (aOR=0.49, college vs. less than high school). HTLV testing with a dual-EIA strategy is feasible and can be useful in areas with low resources. Incidence and residual risk of HTLV-1 transmission by transfusion were relatively high and could be reduced by improving donor recruitment and selection in high prevalence areas. Blood center data may contribute to surveillance for HTLV infection