CESAR DE ALMEIDA NETO
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- Molecular characterization of viruses associated with encephalitis in Sao Paulo, Brazil(2019) FERREIRA, Jerenice E.; FERREIRA, Suzete C.; ALMEIDA-NETO, Cesar; NISHIYA, Anna S.; ALENCAR, Cecilia S.; GOUVEIA, Gisele R.; CAIAFFA-FILHO, Helio; GOMES, Helio; SANTOSID, Raimunda Telma de Macedo; WITKIN, Steven S.; MENDRONE-JUNIOR, Alfredo; SABINO, Ester C.The objective of this study was to characterize the prevalence of viral encephalitis due to arbovirus infection of the Togaviridae and Flaviviridae families in Sao Paulo, Brazil. A total of 500 cerebrospinal fluid (CSF) samples collected between August 2012 and January 2013, from patients with symptoms of acute encephalitis were analyzed. Findings suggestive of viral encephalitis-elevations in cell concentration, glucose and total protein-were observed in 234 (46.8%) samples, designated as Group 1. The remaining 266 samples comprised Group 2. All samples were tested for Flaviviruses (dengue virus 1, 2, 3 and 4, yellow fever virus and West Nile virus), Alphavirus (NS5 region) and enterovirus by RT-PCR and for herpesviruses and enteroviruses using CLART(-)Entherpex. A presumptive viral etiological agent was detected in 26 samples (5.2%), 18 (8.0%) in Group 1 and 8 (3.0%) in Group 2. In Group 1 human herpesviruses were detected in 9 cases, enteroviruses in 7 cases, dengue viruses (DENV) in 2 CSFs and St. Louis encephalitis virus (SLEV) in one case. In Group 2 there were 3 CSFs positive for human herpesviruses, 2 for enteroviruses, 2 for DENV and 1 for SLEV. Detection of arboviruses, even though present in a minority of infected patients, identifies these viruses as a probable etiological agent of encephalitis. This is of special concern in regions where this class of viruses is endemic and has been linked to other recent epidemics.
- HCV Genotypes, Characterization of Mutations Conferring Drug Resistance to Protease Inhibitors, and Risk Factors among Blood Donors in Sao Paulo, Brazil(2014) NISHIYA, Anna S.; ALMEIDA-NETO, Cesar de; FERREIRA, Suzete C.; ALENCAR, Cecilia S.; DI-LORENZO-OLIVEIRA, Claudia; LEVI, Jose E.; SALLES, Nanci A.; MENDRONE JR., Alfredo; SABINO, Ester C.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.
- HIV primary drug resistance and associated HIV risk factors among HIV positive blood donors in Brazil from 2007 to 2017(2021) MOREIRA, Carlos Henrique Valente; SALOMON, Tassila; ALENCAR, Cecilia S.; GONCALEZ, Thelma T.; SABINO, Ester C.; PREISS, Liliana; LOUREIRO, Paula; LOPES, Maria Esther; TEIXEIRA, Carolina Miranda; MUNDIM, Mariana; CARNEIRO-PROIETTI, Anna Barbara; ALMEIDA-NETO, Cesar de; CUSTER, BrianBackground Acquisition of HIV primary drug resistant (PDR) infection can lead to poor virologic and clinical outcomes in individuals and hampers public health efforts in epidemic control. Monitoring PDR in HIV-positive blood donors can be used to inform nationwide trends in the spread of drug-resistant HIV strains. Methods We conducted a cross-sectional study using genetic sequence analysis to assess HIV pol sequences, PDR, and risk factors for infection using audio computer-assisted structured interviews in four large blood centers in Brazil from 2007 to 2017. Results Of 716 HIV-positive blood donors, 504 (70.4%) were successfully sequenced. HIV clade B (73.2%) was the most prevalent subtype, followed by a mix of non-B (21.2%) sub-types. A twofold increase (from 4% to 8%) in recombinants prevalence was observed during the study period. Sixty-four (12.7%) presented PDR. Overall, HIV PDR prevalence remained stable during the study period. Drug resistance mutations for non-nucleoside reverse transcriptase inhibitors were found in 39 (7.7%) donors, while for nucleoside reverse transcriptase inhibitors were found in 26 (5.1%), and for protease inhibitors in 24 (4.8%) of HIV-infected donors. We did not find statistically significant differences in demographics, behavioural risk factors, or HIV genotypes when comparing volunteers with and without PDR. Conclusion The HIV PDR rate among donors remained stable during the study period. HIV-positive blood donors can be an informative population to monitor primary HIV resistance and ultimately may help to increase the knowledge and awareness of HIV risk factors and PDR.
- 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.
- Phylogenetic analysis of the emergence of main hepatitis C virus subtypes in Sao Paulo, Brazil(2015) NISHIYA, Anna Shoko; ALMEIDA-NETO, Cesar de; ROMANO, Camila Malta; ALENCAR, Ceclia Salete; FERREIRA, Suzete Cleusa; DI-LORENZO-OLIVEIRA, Claudia; LEVI, Jose Eduardo; SALLES, Nanci Alves; MENDRONE-JUNIOR, Alfredo; SABINO, Ester CerdeiraBackground: It is recognized that hepatitis C virus subtypes (1a, 1b, 2a, 2b, 2c and 3a) originated in Africa and Asia and spread worldwide exponentially during the Second World War (1940) through the transfusion of contaminated blood products, invasive medical and dental procedures, and intravenous drug use. The entry of hepatitis C virus subtypes into different regions occurred at distinct times, presenting exponential growth rates of larger or smaller spread. Our study estimated the growth and spread of the most prevalent subtypes currently circulating in Sao Paulo. Methods: A total of 465 non-structural region 5B sequences of hepatitis C virus covering a 14-year time-span were used to reconstruct the population history and estimate the population dynamics and Time to Most Recent Common Ancestor of genotypes using the Bayesian Markov Chain Monte Carlo approach implemented in BEAST (Bayesian evolutionary analysis by sampling tree software/program). Results: Evolutionary analysis demonstrated that the different hepatitis C virus subtypes had distinct growth patterns. The introduction of hepatitis C virus-la and -3a were estimated to be circa 1979 and 1967, respectively, whereas hepatitis C virus-1b appears to have a more ancient entry, circa 1923. Hepatitis C virus-1b phylogenies suggest that different lineages circulate in Sao Paulo, and four well-supported groups (i.e., G1, G2, G3 and G4) were identified. Hepatitis C virus-la presented the highest growth rate (r=0.4), but its spread became less marked after the 2000s. Hepatitis C virus-3a grew exponentially until the 1990s and had an intermediate growth rate (r=0.32). An evident exponential growth (r=0.26) was found for hepatitis C virus-1b between 1980 and the mid-1990s. Conclusions: After an initial period of exponential growth, the expansion of the three main subtypes began to decrease. Hepatitis C virus-1b presented inflated genetic diversity, and its transmission may have been sustained by different generations and transmission routes other than blood transfusion. Hepatitis C virus-1a and -3a showed no group stratification, most likely due to their recent entry.
- 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.