SEROLOGIC SURVEY ON HANTAVIRUS IN BLOOD DONORS FROM THE STATE OF SANTA CATARINA, BRAZIL

Emergent diseases such as Hantavirus Cardio-pulmonary Syndrome (HCPS) are able to create a significant impact on human populations due to their seriousness and high fatality rate. Santa Catarina, located in the South of Brazil, is the leading state for HCPS with 267 reported cases from 1999 to 2011. We present here a serological survey on hantavirus in blood donors from different cities of the state of Santa Catarina, with an IgG-ELISA using a recombinant nucleocapsid protein from Araraquara hantavirus as an antigen. In total, 314 donors from blood banks participated in the study, geographically covering the whole state. Among these, 14 individuals (4.4%) had antibodies to hantavirus: four of 50 (8% positivity) from Blumenau, four of 52 (7.6%) from Joinville, three of 50 (6%) from Florianópolis, two of 50 (4%) from Chapecó and one of 35 (2.8%) from Joaçaba. It is possible that hantaviruses are circulating across almost the whole state, with important epidemiological implications. Considering that the seropositive blood donors are healthy individuals, it is possible that hantaviruses may be causing unrecognized infections, which are either asymptomatic or clinically nonspecific, in addition to HCPS. It is also possible that more than one hantavirus type could be circulating in this region, causing mostly benign infections.

The electron transfer complex between nitrous oxide reductase and its electron donors

J Biol Inorg Chem (2011) 16:1241–1254 DOI 10.1007/s00775-011-0812-9

Detection of HTLV-IIa in blood donors in an urban area of the Amazon Region of Brazil (Belém, PA)

The human lymphotropic viruses type I (HTLV-I) and type II (HTLV-II) are members of a group of mammalian retroviruses with similar biological properties, and blood transfusion is an important route of transmission. HTLV-I is endemic in a number of different geographical areas and is associated with several clinical disorders. HTLV-II is endemic in several Indian groups of the Americas and intravenous drug abusers in North and South America, Europe and Southeast Asia. During the year of 1995, all blood donors tested positive to HTLV-I/II in the State Blood Bank (HEMOPA), were directed to a physician and to the Virus Laboratory at the Universidade Federal do Pará for counselling and laboratory diagnosis confirmation. Thirty-five sera were tested by an enzyme immune assay, and a Western blot that discriminates HTLV-I and HTLV-II infection. Two HTLV-II positive samples were submitted to PCR analysis of pX and env genomic region, and confirmed to be of subtype IIa. This is the first detection in Belém of the presence of HTLV-IIa infection among blood donors. This result emphasizes that HTLV-II is also present in urban areas of the Amazon region of Brazil and highlights the need to include screening tests that are capable to detect antibodies for both types of HTLV.

Epidemiological profile of hepatitis C in blood donors at the Uberaba Regional Blood Center

The aim of the present study was to outline the serological profile of hepatitis C among blood donors seen at the Uberaba Regional Blood Center, Hemominas Foundation, over the last 14 years. The frequency of hepatitis C was compared between first-time and repeat donors and the epidemiological characteristics of those with positive and indeterminate ELISA anti-HCV (third and fourth generation) were analyzed based on the donor histories kept in the archives of the Uberaba Regional Blood Center. The serological ineligibility rate was 0.3%, with higher prevalence in the group of first-time donors. We did not find any significant differences regarding age, skin color, marital status or place of residence between eligible and ineligible donors; however, the frequency of positive serology was higher among men. The lower (0.3%) rate of ineligibility due to hepatitis C that was observed at the Uberaba Regional Blood Center, in relation to most Brazilian blood centers, is probably due to the large number of repeat donors (83.3%). This reinforces the importance of achieving donor commitment for increasing transfusion safety.

Evaluation of the use of real-time PCR for human T cell lymphotropic virus 1 and 2 as a confirmatory test in screening for blood donors

INTRODUCTION: HTLV-1/2 screening among blood donors commonly utilizes an enzyme-linked immunosorbent assay (EIA), followed by a confirmatory method such as Western blot (WB) if the EIA is positive. However, this algorithm yields a high rate of inconclusive results, and is expensive. METHODS: Two qualitative real-time PCR assays were developed to detect HTLV-1 and 2, and a total of 318 samples were tested (152 blood donors, 108 asymptomatic carriers, 26 HAM/TSP patients and 30 seronegative individuals). RESULTS: The sensitivity and specificity of PCR in comparison with WB results were 99.4% and 98.5%, respectively. PCR tests were more efficient for identifying the virus type, detecting HTLV-2 infection and defining inconclusive cases. CONCLUSIONS: Because real-time PCR is sensitive and practical and costs much less than WB, this technique can be used as a confirmatory test for HTLV in blood banks, as a replacement for WB.

Seroprevalence of cytomegalovirus antibodies in blood donors in southern, Brazil

INTRODUCTION: Cytomegalovirus (CMV) infection is a matter of concern for blood bank professionals and blood transfusion recipients, especially in cases of transfusions to neonates and immunocompromised patients. Thus, the present study aimed to determine the seroprevalence of CMV IgG and IgM antibodies among blood donors in the city of Lages, in the mountain region of Santa Catarina, southern Brazil, and to investigate possible associations between the socioeconomic characteristics of donors and CMV serological status. METHODS: A seroepidemiological cross-sectional study was conducted on 1,045 blood samples from donors that were used in serological screening over a one-year investigation. All the analyses were conducted using the microparticle enzyme immunoassay with Biokit® reagents (Barcelona, Spain), in accordance with the manufacturer's instructions. RESULTS: Anti-CMV IgG seroprevalence in the sample studied was 96.4% (95% CI: 95.23 - 97.50) and that of anti-CMV IgM was 2.3% (95% CI: 1.39 - 3.20). There were no statistically significant associations between the presence of antibodies and the socioeconomic characteristics of donors. CONCLUSIONS: The blood donors in the study region had high seroprevalence of anti-CMV IgG. Thus, blood component screening strategies and careful indication for blood transfusions require special attention among healthcare professionals as part of the actions for prevention and reduction of primary infections caused by CMV.

Decline in prevalence and asymmetric distribution of human T cell lymphotropic virus 1 and 2 in blood donors, State of Minas Gerais, Brazil, 1993 to 2007

INTRODUCTION: Human T cell lymphotropic virus types 1 and 2 (HTLV-1/2) are endemic in Brazil and are screened for in transfusion services since 1993. This study evaluated the evolution of the prevalence of HTLV-1 and 2 in blood donors of the Hemominas Foundation from 1993 to 2007, and its geographical distribution in State of Minas Gerais, Brazil. METHODS: The Hemominas Foundation is a centralized blood center in Minas Gerais, Brazil. The sources of data were the Hemominas Foundation Technical Bulletin and files from the centralized serological laboratory. Donors were tested in the period using enzyme linked immuno sorbent assays (ELISA), followed by Western blot, when repeatedly reactive. The data were analyzed by EPIINFO 6.2 and TABWIN 3.5 softwares. RESULTS: The average seroprevalence in the period 1993-2007 was 0.1%. A steady decline occurred from 0.4% in 1993 to below 0.1% in 2002 and later, with a transient peak of 0.5% in 1994. HTLV reactivity distribution was asymmetrical in the state, with regions of higher prevalence, interspersed with low prevalence areas. Comparison of positive and negative donors verified that increasing age was proportional to virus positivity. Odds ratio for age ranged from 1.43 (30 to 39 years-old) to 3.09 (50 to 65 years-old). Women had a greater chance of being positive (OR-1.64), as previously described. CONCLUSIONS: Possible explanations for HTLV-1/2 prevalence decline are the exclusion of positive donors from the donor pool, an increase in repeat donors and ELISA test improvement, with reduction in the number of false positive results.

Clinical and epidemiological profile of blood donors with positive serology for viral hepatitis in southern Brazil

INTRODUCTION: Positive serological tests for hepatitis viruses B and C at blood banks are an important reason for blood deferral. Additionally, high residual risk for transfusing hepatitis-contaminated blood has been estimated in southern Brazil. This study aimed to identify risk factors for positive serological tests for viral hepatitis (VH) in blood donors (BD). METHODS: A case-control study included consecutive BD with positive serology for VH, between 2008 and 2009. Cases and controls (BD with negative serology for VH) were paired 1:1 by sex and donation date. Assessment of clinical and epidemiological characteristics related to viral hepatitis was conducted. RESULTS: Among 1,282 blood donors (641 cases and 641 controls), those with positive serology for viral hepatitis had higher mean age (p<0.001); higher proportion of replacement donation (p<0.001); first donation (p<0.001); and interviewer deferment (p=0.037), compared to controls. Furthermore, donors with positive tests were less regular donors (p<0.001), had less previous history of rejection (p=0.003) and showed lower hematocrit median before donation (p=0.019). Multivariate analysis demonstrated that age (OR=1.056, 95%CI 1.042-1.069, p<0.001), replacement donation (OR=1.545, 95%CI 1.171-2.038, p=0.002) and first donation (OR=9.931, 95%CI 7.486-13.173, p<0.001) were independently associated with positivity of serological tests for viral hepatitis. CONCLUSIONS: Specific characteristics of blood donors were associated with positive serology for viral hepatitis. These peculiarities should be taken into account when assessing candidates for blood donation.

Prevalence of Chagas disease in blood donors at the Uberaba Regional Blood Center, Brazil, from 1995 to 2009

INTRODUCTION: A retrospective study was conducted to assess the occurrence of blood donations that were ineligible due to Chagas disease infection from 1995 to 2009 at the Uberaba Regional Blood Center (HRU), Brazil, verify the tendency of this ineligibility, and describe the epidemiologic profile of the donors. METHODS: Retrospective studies of serological ineligibility due to Chagas disease, statistical analysis by means of the chi-square test and odds ratio, study of the tendencies using a dispersion graph and the linear correlation coefficient (r) were performed. RESULTS: In the period under study, a 0.2% serum prevalence of ineligibility due to Chagas disease was found, with a significant drop in ineligible donations from 2001 to 2009. Among the serum positive-donors, there was a significant predominance among those aged 30 years or above and non-single individuals. CONCLUSIONS: The results show a rate of occurrence that is lower than that described in literature, as well as a progressive drop during the 15 years under assessment. Such results are a consequence of systematic combat of the vector since the 70s and the progressive and consistent increase of returning donors, resulting in a drop of the contamination risk factor by means of blood transfusion and in the improvement of the quality of hemotherapy practices in the HRU.

Indeterminate RIBA results were associated with the absence of hepatitis C virus RNA (HCV-RNA) in blood donors

Introduction: Hepatitis C virus (HCV) infection is diagnosed by the presence of antibodies and is supplemented by confirmatory testing methods, such as recombinant immunoblot assay (RIBA) and HCV-RNA detection. This study aimed to evaluate the efficacy of RIBA testing to diagnose HCV infection in blood donors positive for anti-HCV antibodies. Methods: A total of 102 subjects positive for anti-HCV determined by enzyme-linked immunosorbent assay (ELISA) at the Hematology and Hemotherapy Foundation of Bahia (HEMOBA) were later assessed with new samples using the Abbott Architect anti-HCV test (Abbott Diagnostics, Wiesbaden, Germany), the RIBA III test (Chiron RIBA HCV 3.0 SIA, Chiron Corp., Emeryville, CA, USA), the polymerase chain reaction (PCR; COBAS® AMPLICOR HCV Roche Diagnostics Corp., Indianapolis, IN, USA) and line probe assay (LiPA - Siemens, Tarrytown, NY, USA) genotyping for HCV diagnosis. Results: Of these new samples, 38.2% (39/102) were positive, 57.8% (59/102) were negative and 3.9% (4/102) were indeterminate for anti-HCV; HCV-RNA was detected in 22.5% (23/102) of the samples. RIBA results were positive in 58.1% (25/43), negative in 9.3% (4/43) and indeterminate in 32.6% (14/43) of the samples. The prevailing genotypes were 1 (78.3%, 18/23), 3 (17.4%, 4/23) and 2 (4.3%, 1/23). All 14 samples with indeterminate RIBA results had undetectable viral loads (detection limit ≤50 IU/mL). Of these samples, 71.4% (10/14) were reevaluated six months later. Eighty percent (8/10) of these samples remained indeterminate by RIBA, and 20% (2/10) were negative. Conclusions: In this study, individuals with indeterminate RIBA results had no detectable HCV-RNA.

Syphilis seroprevalence estimates of Santa Catarina blood donors in 2010

Introduction Knowledge of blood donor characteristics is essential to better guide clinical and serological screening for hemotherapy. The objective of this study was to determine the syphilis seroprevalence and the associated factors of blood donors in the State of Santa Catarina, Brazil. Methods This population-based study from the State of Santa Catarina used information obtained from blood donation records. We analyzed 83,396 blood donor records generated from donors who were considered eligible to donate between January and August 2010. The aim of the study was to estimate the syphilis seroprevalence and its relationship with educational level, age, gender, geographical region and having donated blood in the past 12 months. We used descriptive analyses and a Poisson regression to calculate the prevalence ratios for the variables of interest. Results We found a 0.14% overall seroprevalence and significant differences among the following: first-time blood donors (0.19%) versus repeat donors (0.03% to 0.08%); low educational levels (0.30%) versus medium and high educational levels (0.08% to 0.19%); and donors who did not report their residence (0.88%) or age (6.94%) versus those who did. Increased syphilis seroprevalence was also significantly associated with increased age. Conclusion High syphilis seroprevalence was associated with lower educational level, age, first-time donation and the failure to provide age or residence information.

Changes in the prevalence, incidence and residual risk for HIV and hepatitis C virus in Southern Brazilian blood donors since the implementation of NAT screening

Introduction Previous studies have shown high residual risk of transfusing a blood donation contaminated by human immunodeficiency virus (HIV) or hepatitis C virus (HCV) in Brazil and motivated the development of a Brazilian platform for simultaneous detection of both viruses by nucleic acid amplification test (NAT) denominated HIV/HCV Bio-Manguinhos/Fundação Oswaldo Cruz (FIOCRUZ). The objective of this study was to verify seroprevalence, incidence and residual risk for both viruses before and after the implementation of NAT. Methods Over 700,000 blood samples from all blood banks in the southern Brazilian State of Santa Catarina were analyzed during the period between January 2007 and July 2013. Results Compared with the period preceding the NAT screening, HIV prevalence increased from 1.38 to 1.58 per 1,000 donors, HIV incidence rate increased from 1.22 to 1.35 per 1,000 donor-years, and HIV residual risk dropped almost 2.5 times during the NAT period. For HCV, seroprevalence increased from 1.22 to 1.35 per 1,000 donors, incidence dropped from 0.12 to 0.06 per 1,000 donor-years, and residual risk decreased more than 3 times after the NAT implementation. Conclusions NAT reduced the duration of the immunologic window for HIV and HCV, thus corresponding to approximately 2.5- and 3-fold respective residual risk reductions.

Clinical and epidemiological profile of female blood donors with positive serology for viral hepatitis B

ABSTRACTINTRODUCTION:Since women are frequently the minority among blood donors worldwide, studies evaluating this population usually reflect male features. We assessed the features of female blood donors with positive serology for HBV and compared them with those of men.METHODS The study comprised consecutive blood donors referred to a specialized liver disease center to be evaluated due to HBsAg- and/or anti-HBc-positive tests.RESULTS: The study encompassed 1,273 individuals, 219 (17.2%) of whom were referred due to positive HBsAg test and 1,054 (82.8%) due to reactive anti-HBc test. Subjects' mean age was 36.8±10.9 years, and 28.7% were women. Female blood donors referred for positive HBsAg screening tests demonstrated higher prevalence of healthcare workers (9.3% vs 2.5%) and lower prevalence of sexual risk behaviors (15.1% vs 41.1%) and alcohol abuse (1.9% vs 19.8%) compared to men. Women had lower ALT (0.6 vs 0.8×ULN), AST (0.6 vs 0.8×ULN), direct bilirubin (0.2 vs 0.3mg/dL), and alkaline phosphatase (0.5 vs 0.6×ULN) levels and higher platelet count (223,380±50,293 vs 195,020±53,060/mm3). Women also had a higher prevalence of false-positive results (29.6% vs 17.0%). No differences were observed with respect to liver biopsies. Female blood donors referenced for reactive anti-HBc screening tests presented similar clinical, epidemiological, and biochemical characteristics to those reported for positive HBsAg screening tests and similarly had a higher prevalence of false-reactive results.CONCLUSIONS: Compared to men, female blood donors with positive HBsAg and/or anti-HBc screening tests demonstrated higher prevalence of professional risk and false-positive results and reduced alteration of liver chemistry.

Presence of anti-Leishmania (Viannia) braziliensis antibodies in blood donors in the West-Central region of the State of Paraná, Brazil

ABSTRACTINTRODUCTION:Serological screening in blood banks does not include all transmittable diseases. American cutaneous leishmaniasis (ACL) has a high detection rate in the municipalities of the State of Paraná.METHODS:This study analyzed the presence of anti- Leishmania braziliensisantibodies in 176 blood donors who live in these endemic areas. The variables were analyzed with the χ2 test and Stata 9.1 software. RESULTS: Twenty (11.4%) samples were positive for the presence of anti- L. braziliensisantibodies. CONCLUSIONS: The high percentage of donors with anti- Leishmania spp. antibodies indicates the need to study the risk of ACL transmission through blood donors.