CESAR DE ALMEIDA NETO
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- Detection and analysis of blood donors seropositive for syphilis(2021) ATTIE, Adriana; ALMEIDA-NETO, Cesar de; WITKIN, Steven S.; DERRIGA, Juliana; NISHIYA, Anna S.; FERREIRA, Jerenice E.; COSTA, Natalia de Souza Xavier; SALLES, Nanci Alves; FACINCANI, Tila; LEVI, Jose E.; SABINO, Ester C.; ROCHA, Vanderson; MENDRONE-JR, Alfredo; FERREIRA, Suzete C.Background The increasing incidence of syphilis worldwide has called attention to the risk of transmission by transfusion. Aims To determine the prevalence of active syphilis in blood donors and characterise the serological profile of syphilis-positive donors. Methods Samples positive for Treponema pallidum using the chemiluminescent microparticle immunoassay (CMIA) during blood donor screening from 2017 to 2018 were tested by the Venereal Disease Research Laboratory (VDRL) non-treponemal test and for anti-T. pallidum IgM by ELISA (Immunoassay Enzyme test for detection of IgM antibodies). The INNO-LIA Syphilis test (Line Immuno Assay solid test for confirmation antibodies to Treponema pallidum) was performed as a confirmatory test on samples that were positive on ELISA-IgM but negative on VDRL. ELISA-IgM (+) samples were also tested for T. pallidum DNA in sera by real-time polymerase chain reaction (PCR). Results Of 248 542 samples screened, 1679 (0.67%) were positive for syphilis by CMIA. Further analysis was performed on 1144 (68.1%) of these samples. Of those tested, 16% were ELISA IgM(+)/VDRL(+), 16.5% were ELISA IgM(-)/VDRL(+), 4.1% were ELISA IgM(+)/VDRL(-), and 63.4% were ELISA IgM (-)/VDRL(-). The INNO-LIA Syphilis test results were 33 (3%) positive, 2 (0.2%) undetermined and 12 (1%) negative. Of the 230 EIA-IgM(+) samples (20.1%), 5 (2.2%) were PCR positive. The prevalence of active syphilis in 2017 and 2018 was 0.1% and 0.07%, respectively, and overall prevalence of serologic markers for syphilis was highest among male, unmarried, 25-34-year-olds with a high school education and who were first-time donors. Conclusion There is a risk of transfusion-transmitted syphilis in blood banks that exclusively use the VDRL test for donor screening, as is currently the situation in some Brazilian blood centres, as well as in other blood centres around the world.
- Occult and active hepatitis B virus detection in donated blood in Sao Paulo, Brazil(2021) NISHIYA, Anna S.; LEVI, Jose E.; ALMEIDA-NETO, Cesar de; WITKIN, Steven S.; FERREIRA, Suzete C.; BASSIT, Leda; SABINO, Ester C.; DI-LORENZO-OLIVEIRA, Claudia; SALLES, Nanci A.; COUTINHO, Adenilson S.; BELLESA, Maria A.; ROCHA, Vanderson; MENDRONE-JR, AlfredoBackground The present study determined the HBV antigen, antibody, and DNA status in blood donations deemed to be HBV positive. Individuals with an occult HBV infection (OBI), defined as being positive for HBV DNA but negative for HBV surface antigen (HBsAg), as well as those with active infection (HBsAg-positive), were identified and characterized. Study Design and Methods From a total pool if 198,363 blood donations, we evaluated in a cross-sectional study, 1106 samples that were positive in screening tests for antibody to HBV core antigen (HBcAb), HBsAg, and/or HBV DNA by nucleic acid testing (NAT-HBV). The presence of genetic variants in the HBV pol/S gene in individuals with an active HBV infection was also determined. Results OBIs were detected in six of 976 samples (0.6%) that were positive only for HBcAb. The rate of HBV active infection was 0.024% (48/198,363) and there was a predominance of HBV sub-genotype A1 (62.2%, 28/45), followed by D3 (17.8%, 8/45). Mutations in the S gene were found in 57.8% (26/45) and immune escape mutations in 37.8% (17/45) of active HBV-infected donors. Among them, T123N, G145A, and D144G high-impact immune escape mutations were identified. Conclusion Highly sensitive molecular tests improve the capacity to detect OBIs. When NAT is performed in pooled samples, HBcAb test has value in the detection of donors with OBI and improves transfusion safety. Mutations in the S gene are frequent in HBsAg-positive blood, including those associated with diagnostic failure and vaccine escape mutations.
- Three-quarters attack rate of SARS-CoV-2 in the Brazilian Amazon during a largely unmitigated epidemic(2021) BUSS, Lewis F.; JR, Carlos A. Prete; ABRAHIM, Claudia M. M.; JR, Alfredo Mendrone; SALOMON, Tassila; ALMEIDA-NETO, Cesar de; FRANCA, Rafael F. O.; BELOTTI, Maria C.; CARVALHO, Maria P. S. S.; COSTA, Allyson G.; CRISPIM, Myuki A. E.; FERREIRA, Suzete C.; FRAIJI, Nelson A.; GURZENDA, Susie; WHITTAKER, Charles; KAMAURA, Leonardo T.; TAKECIAN, Pedro L.; PEIXOTO, Pedro da Silva; OIKAWA, Marcio K.; NISHIYA, Anna S.; ROCHA, Vanderson; SALLES, Nanci A.; SANTOS, Andreza Aruska de Souza; SILVA, Martirene A. da; CUSTER, Brian; V, Kris Parag; BARRAL-NETTO, Manoel; KRAEMER, Moritz U. G.; PEREIRA, Rafael H. M.; PYBUS, Oliver G.; BUSCH, Michael P.; CASTRO, Marcia C.; DYE, Christopher; NASCIMENTO, Vitor H.; FARIA, Nuno R.; SABINO, Ester C.Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spread rapidly in Manaus, the capital of Amazonas state in northern Brazil. The attack rate there is an estimate of the final size of the largely unmitigated epidemic that occurred in Manaus. We use a convenience sample of blood donors to show that by June 2020, 1 month after the epidemic peak in Manaus, 44% of the population had detectable immunoglobulin G (IgG) antibodies. Correcting for cases without a detectable antibody response and for antibody waning, we estimate a 66% attack rate in June, rising to 76% in October. This is higher than in Sao Paulo, in southeastern Brazil, where the estimated attack rate in October was 29%. These results confirm that when poorly controlled, COVID-19 can infect a large proportion of the population, causing high mortality.
- Correlation between SARS-COV-2 antibody screening by immunoassay and neutralizing antibody testing(2021) MENDRONE-JUNIOR, Alfredo; DINARDO, Carla Luana; FERREIRA, Suzete Cleuza; NISHYA, Anna; SALLES, Nanci Alves; ALMEIDA NETO, Cesar de; HAMASAKI, Debora Toshei; FACINCANI, Tila; ALVES, Lucas Bassolli de Oliveira; MACHADO, Rafael Rahal Guaragna; ARAUJO, Danielle Bastos; DURIGON, Edison Luiz; ROCHA, Vanderson; SABINO, Ester CerdeiraBackground The efficacy of convalescent plasma (CP), an alternative for the treatment of COVID-19, depends on high titers of neutralizing antibodies (nAbs), but assays for quantifying nAbs are not widely available. Our goal was to develop a strategy to predict high titers of nAbs based on the results of anti-SARS-CoV-2 immunoassays and the clinical characteristics of CP donors. Study Design and Methods A total of 214 CP donors were enrolled and tested for the presence of anti-SARS-CoV-2 antibodies (IgG) using two commercial immunoassays: EUROIMMUN (ELISA) and Abbott (Chemiluminescence). Quantification of nAbs was performed using the Cytopathic Effect-based Virus Neutralization test. Three criteria for identifying donors with nAbs >= 1:160 were tested: - C1: Curve ROC; - C2: Conditional decision tree considering only the IA results and - C3: Conditional decision tree including both the IA results and the clinical variables. Results The performance of the immunoassays was similar referring to both S/CO and predictive value for identifying nAbs titers >= 1:160. Regarding the studied criteria for identifying CP donors with high nAbs titers: (a) C1 showed 76.1% accuracy if S/CO = 4.65, (b) C2 presented 76.1% accuracy if S/CO >= 4.57 and (c) C3 had 71.6% accuracy if S/CO was >= 4.57 or if S/CO was between 2.68-4.57 and the last COVID-19-related symptoms were recent (within 19 days). Conclusion SARS-CoV-2 IgG immunoassays (S/CO) can be used to predict high anti-SARS-CoV-2 nAbs titers. This study has proposed different criteria for identifying donors with >= 1:160 nAbs titers, all with high efficacy.
- Demographic, risk factors and motivations among blood donors with reactive serologic tests for syphilis in SAo Paulo, Brazil(2014) FERREIRA, S. C.; ALMEIDA-NETO, C. de; NISHIYA, A. S.; OLIVEIRA, C. D. L.; FERREIRA, J. E.; ALENCAR, C. S.; LEVI, J. E.; SALLES, N. A.; MENDRONE JR., A.; SABINO, E. C.Objective To identify the demographic characteristics, risk factors and motivations for donating among blood donors with reactive serologic tests for syphilis. Background Post-donation interviews with syphilis seropositive blood donors improve recruitment and screening strategies. Methods This case-control study compares 75 Venereal Disease Research Laboratory (VDRL)>8, EIA+ (enzyme immunoassay) and FTA-ABS+ (fluorescent treponemal antibody); 80 VDRL-, EIA+ and FTA-ABS+; and 34 VDRL- and EIA- donors between 2004 and 2009. Donors were assessed by their demographic characteristics, sexual behaviour, history of alcohol and illicit drugs use, and motivations to donate. Results Donors with VDRL>8 were more likely to be divorced [AOR=12 center dot 53; 95% confidence interval (CI) 1 center dot 30-120 center dot 81], to have had more than six sexual partners (AOR=7 center dot 1; 95% CI 1 center dot 12-44 center dot 62) and to report male-male-sex in the past 12months (AOR=8 center dot 18; 95% CI 1 center dot 78-37 center dot 60). Donors with VDRL-, EIA+ and FTA-ABS+ were less likely to be female (AOR=0 center dot 26; 95% CI 0 center dot 07-0 center dot 96), more likely to be older (AOR=10 center dot 2; 95% CI 2 center dot 45-42 center dot 5839 and <60years old) and to have had more than six sexual partners in the past 12months (AOR=8 center dot 37; 95% CI 1 center dot 49-46 center dot 91). There was no significant difference among groups regarding illicit drugs use; 30 center dot 7% (VDRL>8) and 12 center dot 5% (VDRL-, EIA+ and FTA-ABS+) of donors reported that they had been at risk for HIV infection (P=0 center dot 004). One-third of donors came to the blood bank to help a friend or a relative who needed blood. Conclusion Although donors exposed to syphilis reported and recognised some high risk behaviour, most were motivated by direct appeal to donate blood. Monitoring the risk profile of blood donors can benefit public health and improve blood safety.
- Influence of unreported HIV prophylaxis on the kinetics of post-blood donation HIV seroconversion(2021) NISHIYA, Anna S.; SALLES, Nanci A.; ALMEIDA-NETO, Cesar de; WITKIN, Steven S.; FERREIRA, Suzete C.; NOGUEIRA, Fatima A. H.; FACINCANI, Tila; ROCHA, Vanderson; MENDRONE-JR, AlfredoBackground In 2020, of 110,000 blood donors screened for HIV exposure two individuals were identified who were viral RNA-positive but seronegative. One of the donors, borderline negative in a pooled screening test for HIV RNA, utilized antiretroviral drugs as post-exposure, pre-donation prophylaxis. The kinetics of subsequent HIV seropositivity in both donors are described. Study Design and Methods Both donors were recalled and interviewed, and blood was obtained at intervals for HIV antibodies and RNA testing. Results One donor used antiretroviral prophylaxis for 30 days due to a relationship with an HIV-positive partner. In follow-up samples, seroconversion was noted at 70 days, and viral RNA was detected at 105 days, after blood donation. In contrast, the other donor seroconverted in <25 days and the appearance and titer of HIV RNA was in accordance with the typical pre-seroconversion window. Conclusion The use of anti-viral prophylaxis by blood donors in the acute phase of HIV infection delays seroconversion. A 6-month deferral in blood donation after HIV prophylaxis, as currently recommended in Brazil, would have been sufficient in this case to mitigate the risk of transfusion-transmitted HIV. Ultimately, improvement in donor compliance with selection procedures for blood donation is needed to optimize blood safety.
- Improved detection of hepatitis C virus-positive blood donors and determination of infection status(2023) NISHIYA, Anna S.; ALMEIDA-NETO, Cesar de; WITKIN, Steven S.; FERREIRA, Suzete C.; SALLES, Nanci A.; NOGUEIRA, Fatima A. H.; OLIVEIRA, Claudia Di Lorenzo; ROCHA, Vanderson; MENDRONE JUNIOR, AlfredoBackground In low-risk populations, variability in the sensitivity of current serological tests for Hepatitis C virus (HCV) blood donor screening may lead to the presence of false-positive results. This contributes to the unnecessary loss of blood donor samples as well as to difficulty in accurate donor counselling. The present study determined the optimal cut-off value of a chemiluminescent immunoassay for identification of HCV-reactive blood donors. Study Design and Methods In a retrospective cross-sectional analysis of 193 973 blood donations, 578 samples that were positive for HCV antibody in a chemiluminescent immunoassay and/or RNA screening tests were identified. Blood from 379 of these positive samples was available for retesting by a second confirmatory HCV immunoassay followed by a receiver operating characteristic (ROC) curve analysis. Donors were also recalled for a new analysis. Results Only 71 (18.7%) blood samples remained HCV-positive upon retesting, while 233 (61.5%) now tested negative and 75 (19.8%) yielding indeterminate results. A signal to cutoff ratio >= 4.32 was determined as the best differential threshold between a positive and negative result, increasing the positive predictive value from 27.3% to 66.7%. Conclusion Using a higher threshold for an HCV-positive blood sample enhances the chemiluminescent immunoassay screening test ' s accuracy and helps to improve donor counselling and notification processes.
- Prevalence of Treponema pallidum DNA among blood donors with two different serologic tests profiles for syphilis in Sao Paulo, Brazil(2014) FERREIRA, S. C.; ALMEIDA-NETO, C. de; NISHIYA, A. S.; DI-LORENZO-OLIVEIRA, C.; FERREIRA, J. E.; ALENCAR, C. S.; LEVI, J. E.; SALLES, N. A.; MENDRONE-JUNIOR, A.; SABINO, E. C.The presence of Treponema pallidum DNA was assessed by real-time PCR in samples of blood donors with reactive serologic tests for syphilis. Treponema pallidum DNA was detected in two (1 center dot 02%) of 197 samples of VDRL>8, EIA+ and FTA-ABS+ donors, and in no sample from 80 VDRL-, EIA+ and FTA-ABS+ donors. Donors VDRL-, EIA+ and FTA-ABS+ lack demonstrable T.pallidum DNA in their blood and are unlike to transmit syphilis. Donors VDRL>8, EIA+ and FTA-ABS+ carry the risk of syphilis infectivity even in concomitance to antibodies detection. Serologic screening for syphilis may still play a role to prevent its transfusion transmission.
- Detection of unreported usage of the antiretroviral drug lamivudine in two blood donors(2023) NISHIYA, Anna; SALLES, Nanci; ALMEIDA-NETO, Cesar de; FERREIRA, Suzete; NOGUEIRA, Fatima; ROCHA, Vanderson; MENDRONE, AlfredoBackground Unreported HIV antiretroviral (ARV) drug usage by blood donors compromises the ability to detect evidence of HIV infection in blood screening tests and represents a risk for blood transfusion safety. Our objective was to determine the frequency of undeclared ARV drug use by blood donors with altered HIV markers.Study Design and Methods This was a retrospective cross-sectional analysis of donations that were tested for HIV antibody (ab), antigen (ag), and RNA by chemiluminescent immunoassay and nucleic acid screening tests. Positive samples were retested and were subjected to ARV drug testing by high-performance liquid chromatography-tandem mass spectrometry.Results Of 345,252 blood donations, 361 (0.1%) were positive on initial testing. Samples from 296 (81.9%) of these donations were available for further analysis. The presence of HIV ab/ag and/or RNA was confirmed in 83 (28.0%) of these samples. All 296 bloods were subjected to ARV testing. The ARV drug lamivudine, at 11.3 and 6.7 ng/mL, was detected in 2 of 83 (2.4%) donations that were HIV positive. Other drugs were not detected.Conclusion Unreported ARV usage was identified in two candidates for blood donation. More intensive efforts to educate donors about disclosure and to investigate the extent of this phenomenon in Brazil are needed.