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    Elisabeth Lampe

    Testing of the DNA of TT virus (TTV) was done with serum samples obtained from 191 persons working in a public hospital of the city of Rio de Janeiro, Brazil. TTV DNA was detected by PCR in the sera of 125 (65.4%) individuals. PCR... more
    Testing of the DNA of TT virus (TTV) was done with serum samples obtained from 191 persons working in a public hospital of the city of Rio de Janeiro, Brazil. TTV DNA was detected by PCR in the sera of 125 (65.4%) individuals. PCR products were cloned, and sequences with a length of 159 bases surrounding the TATA signal region
    Genotype 5 of hepatitis C virus (HCV) has been rarely identified in South America. A female of African descent who never left Brazil was found to be infected by this genotype in Mato Grosso state, Central Brazil. The patient denied drug... more
    Genotype 5 of hepatitis C virus (HCV) has been rarely identified in South America. A female of African descent who never left Brazil was found to be infected by this genotype in Mato Grosso state, Central Brazil. The patient denied drug injections and revealed that she had received blood transfusions several years before. One of her blood donors was identified
    The Northeast region is the location of most cases of acute hepatitis A virus (HAV) in Brazil. In the present study, the genotypes of HAV strains from Pernambuco State, one of most populous states in the Northeast region, were... more
    The Northeast region is the location of most cases of acute hepatitis A virus (HAV) in Brazil. In the present study, the genotypes of HAV strains from Pernambuco State, one of most populous states in the Northeast region, were characterized. Blood samples positive for anti-HAV IgM from 145 individuals (mean age = 29.1 years), collected during 2002 and 2003, were submitted to nested RT-PCR for amplification of the 5'non-translated region (5'NTR) and VP1/2A regions of the HAV genome. The VP1/2A and 5'NTR regions were amplified in 39 and 21% of the samples, respectively. Nucleotide sequencing was carried out in 46% of VP1/2A and in 53% of 5'NTR isolates. The identity in nucleotide sequence of the VP1/2A region ranged from 93.6 to 100.0%. Phylogenetic analysis of the VP1/2A sequences showed that 65% belong to sub-genotype IA and 35% to sub-genotype IB. Co-circulation of both sub-genotypes was observed in the two years studied. Distinct clusters of highly related sequences were observed in both sub-genotypes, suggesting endemic circulation of HAV strains in this area. In the 5'NTR isolates, 92.7-99.2% identity was observed and two isolates presented one deletion at position 413. Phylogenetic analysis showed that genotype IA strains cluster in the tree in the same way as genotype IB strains, but one IIIA isolate from Spain clusters with genotype IB strains. These results do not allow us to state that 5'NTR could be used to genotype HAV sequences. This is the first report of co-circulation of sub-genotypes IA and IB in this region, providing additional information about the molecular epidemiology of HAV strains in Brazil.
    Men who have sex with men (MSM) are more vulnerable to blood-borne infections and/or sexually-transmitted infections (STI). This study was conducted to estimate the prevalences of mono and co-infections of HIV-1 and other blood-borne/STIs... more
    Men who have sex with men (MSM) are more vulnerable to blood-borne infections and/or sexually-transmitted infections (STI). This study was conducted to estimate the prevalences of mono and co-infections of HIV-1 and other blood-borne/STIs in a sample of MSM in Campinas, Brazil. Responding Driven Sampling (RDS) was used for recruitment of MSM. Serum samples collected from 558 MSM were analyzed for the presence of serological markers for HIV-1, HBV, HCV, HTLV, HPV-16/18, and T. pallidum infections. The highest prevalences of infection in serum samples were found for HPV-16 and 18 (31.9% and 20.3%, respectively). Approximately 8% of the study population showed infection with HIV-1, and within that group, 27.5% had recently become infected with HIV-1. HBV infection and syphilis were detected in 11.4% and 10% of the study population, respectively, and the rates of HTLV and HCV infection were 1.5% and 1%, respectively. With the exception of HTLV, all other studied infections were usually ...
    In Argentina, most information on hepatitis C virus (HCV) genotype distribution comes from studies carried out in Buenos Aires (east province). In order to identify HCV subtypes in central Argentina, nucleotide sequenc- ing of core region... more
    In Argentina, most information on hepatitis C virus (HCV) genotype distribution comes from studies carried out in Buenos Aires (east province). In order to identify HCV subtypes in central Argentina, nucleotide sequenc- ing of core region was performed in samples from 36 patients living in Córdoba, the second most populated province of Argentina. The sequence analysis identified subtype 2c as
    Haemodialysis (HD) continues to carry the risk of hepatitis C virus (HCV) transmission, with delayed seroconversion and often normal alanine aminotransferase (ALT) values increasing the likelihood of undetected infection and thus... more
    Haemodialysis (HD) continues to carry the risk of hepatitis C virus (HCV) transmission, with delayed seroconversion and often normal alanine aminotransferase (ALT) values increasing the likelihood of undetected infection and thus uninterrupted spread of HCV. The aim of this study was to identify the characteristic patterns of ALT changes and seroconversion during an outbreak of HCV in a HD unit. We also wanted to establish the relationship between infecting viruses using molecular analysis. All patients (n = 72) and staff (n = 23) of the HD unit were prospectively followed for 14 months. Serial measurements for ALT, HCV antibody and HCV-RNA were performed besides HCV sequence analysis. The initial screening for anti-HCV and HCV-RNA confirmed chronic infection in 16/72 (22%) subjects and identified three subjects with recent seroconversion. In addition, five cases were reverse transcription-polymerase chain reaction positive alone for a total of eight recent cases. The interval between the initial observation of ALT changes and seroconversion varied from 1 to 8 months, and in several individuals ALT fluctuations only below the upper limit of normal were detected. However, relating each subject's ALT values to ALT at baseline, ALT levels increased between 1.6- and 4.7-fold. Molecular analysis provided evidence for transmission from two chronically infected source patients, probably because of inappropriate infection control measures. Our data highlight the importance of well-implemented safety precautions and regular HCV-RNA testing to prevent the further spread of HCV in this population, and suggest the use of ALT baseline values to identify infections that may remain unnoticed otherwise.
    Hepatitis C virus (HCV) has been a significant problem for hemodialysis patients. However this infection has declined in regions where the screening for anti-HCV in blood banks and hemodialysis-specific infection control measures were... more
    Hepatitis C virus (HCV) has been a significant problem for hemodialysis patients. However this infection has declined in regions where the screening for anti-HCV in blood banks and hemodialysis-specific infection control measures were adopted. In Brazil, these measures were implemented in 1993 and 1996, respectively. In addition, all studied units have implemented isolation of anti-HCV positive patients since 2000. In order to evaluate the impact of these policies in the HCV infection prevalence, accumulated incidence, and risk factors in hemodialysis population of Goiânia City, Central Brazil, all patients were interviewed and serum samples tested for HCV antibodies in 1993, 1996, 1999, and 2002. In the first six years (1993-1999), anti-HCV prevalence increased from 28.2 to 37.2%, however a b decrease in positivity was detected between 1999 and 2002 (37.8 vs 16.5%) when the measures were fully implemented. Also, a decrease of the anti-HCV accumulated incidence in cohorts of susceptible individuals during 1993-2002 (71%), 1996-2002 (34.2%), and 1999-2002 (11.7%) was found. Analysis of risk factors showed that length of time on hemodialysis, blood transfusion before screening for anti-HCV and treatment in multiple units were statistically associated with anti-HCV (p < 0.05). Our study showed a significant decline of hepatitis C infection in hemodialysis patients of Central Brazil, gratifying the importance of public health strategies for control and prevention of hepatitis C in the hemodialysis units.
    Hepatitis A virus (HAV) isolates from around the world have been classified into seven genotypes (I-VII). Most human strains belong to genotype I, which has been divided into two subgenotypes, A and B. South America has provided a small... more
    Hepatitis A virus (HAV) isolates from around the world have been classified into seven genotypes (I-VII). Most human strains belong to genotype I, which has been divided into two subgenotypes, A and B. South America has provided a small number of strains studied at the genome level. In the present study, IgM anti-HAV antibodies were detected in 116 out of 250 (46%) serum samples collected from consecutive patients with acute hepatitis referred to the Brazilian Reference Center for Viral Hepatitis, Rio de Janeiro. Viral RNA were extracted from all 250 samples and submitted to a reverse transcription-polymerase chain reaction (RT-PCR) assay designed to amplify a genome segment in the VP1/2A junction region. HAV RNA was detected in 54/116 (47%) and 17/134 (13%) IgM anti-HAV-positive and -negative sera, respectively. In addition, HAV RNA was detected in 17/35 (49%) IgM anti-HAV-positive sera that had been collected at a day care center where cases of acute hepatitis were being observed for 3 months. Nucleotide sequences (168 bp) of PCR products were determined for 30 HAV isolates. Phylogenetic analysis showed that 21 belonged to subgenotype IB, while 9 were of subgenotype IA. Interestingly, a concomitant circulation of isolates from subgenotypes IA and IB was observed in the day care center.
    The recently discovered GBV-C/hepatitis G virus (GBV-C/HGV) has been shown to be parenterally transmitted. The occurrence of community-acquired GBV-C/HGV infections has also been reported. In order to study the variations with age of the... more
    The recently discovered GBV-C/hepatitis G virus (GBV-C/HGV) has been shown to be parenterally transmitted. The occurrence of community-acquired GBV-C/HGV infections has also been reported. In order to study the variations with age of the GBV-C/HGV prevalence, sera from 268 individuals without liver disease, aged 0-80 years, and living in the city of Rio de Janeiro, Brazil, were tested by reverse transcription-nested polymerase chain reaction for the presence of GBV-C/HGV RNA. Age-specific seroprevalence was low (2.3%) among children under the age of 10, reached a maximum of 18% in young adults (21-30 years), and declined in older age groups. Among 170 blood donors aged 18-60, the rate of individuals with antibodies against the viral envelope E2 protein increased with age, from about 6% between the ages of 18 and 24 to about 35% for individuals from the age of 43 to 60. The results suggest that sexual transmission of GBV-C/HGV might occur and that the virus could be eliminated after a long period of infection. The nucleotide sequences of GBV-C/HGV genome fragments, 422 base pairs (bp) in the E2 region and 354 bp in the nonstructural 5 region, were determined for 11 and 31 isolates, respectively. Phylogenetic tree based on concatenated E2 + NS5 sequences showed that Brazilian strains belonged to three clusters, two of which were previously characterized as genotypes 1 and 2.
    Hepatitis C virus (HCV) subtypes 1a, 1b and 3a are the most prevalent strains in Brazil, but very little is known about the epidemic history of these subtypes in the country. A total of 231 HCV NS5B gene sequences (subtype 1a=89, subtype... more
    Hepatitis C virus (HCV) subtypes 1a, 1b and 3a are the most prevalent strains in Brazil, but very little is known about the epidemic history of these subtypes in the country. A total of 231 HCV NS5B gene sequences (subtype 1a=89, subtype 1b=56, and subtype 3a=86) isolated in Brazil between 1995 and 2007 were analyzed in the present study. Sequences
    Since the identification of hepatitis C virus (HCV) in 1989 as a causative agent for a number of the extrahepatic alterations related to HCV infection an underlying immune mediated pathogenetic mechanism has been postulated.... more
    Since the identification of hepatitis C virus (HCV) in 1989 as a causative agent for a number of the extrahepatic alterations related to HCV infection an underlying immune mediated pathogenetic mechanism has been postulated. HCV-associated thrombocytopenia may be considered complex and multifactorial in origin, since different mechanisms have been implicated in its pathophysiology. With respect to autoimmune thrombocytopenia in chronic HCV infection, the detection of specific antibodies against platelet glycoproteins have been reported only in a few studies, but no systematic study has been carried out. We examined the clinical, laboratory, and virological characteristics of a case series of 10 patients with autoimmune thrombocytopenia (platelet count <150.0 x 10(9)/L) related to chronic HCV infection. Cases, six males and four females, aged 57.1 +/- 12.6 years, presented high titers of antibodies against platelet glycoprotein (GP) IIb/IIIa, GP Ia/IIa, and/or GP Ib/IX, and no other mechanism involved in the pathogenesis of HCV-associated thrombocytopenia was identified. Furthermore, cases were not associated with particular HCV genotype. Complete platelet response was observed in two patients treated with pegylated interferon plus ribavirin, and partial platelet response was seen in two patients treated with anti-D Ig and one patient treated with corticosteroids. These findings indicate that an autoimmune mechanism may play a role in the pathogenesis of HCV-associated thrombocytopenia in a proportion of these patients.
    The natural outcome of infection with hepatitis C virus (HCV) varies substantially among individuals. However, little is known about host and viral factors associated with a self-limiting or chronic evolution of HCV infection. From 1... more
    The natural outcome of infection with hepatitis C virus (HCV) varies substantially among individuals. However, little is known about host and viral factors associated with a self-limiting or chronic evolution of HCV infection. From 1 January 2001 through 31 December 2008, a consecutive series of 65 patients from Rio de Janeiro, Brazil, with a well-documented diagnosis of acute HCV infection, acquired via various routes, were enrolled in this study. Patients were prospectively followed up for a median of 40 months after the estimated date of HCV infection with serial measurements of serum alanine aminotransferase, HCV RNA, and anti-HCV antibodies. Spontaneous viral clearance (SVC) was defined as undetectable levels of HCV RNA in serum, in the absence of treatment, for 3 consecutive HCV polymerase chain reaction tests within the first 6 months of follow-up. Cox proportional hazards regression was used to identify host and viral predictors of SVC. The cumulative rate of SVC was 44.6% (95% confidence interval, 32.3%-57.5%). Compared with chronic HCV evolution, patients with self-limiting disease had significantly lower peak levels of anti-HCV antibodies (median, 109.0 vs 86.7 optical density-to-cutoff ratio [od/co]; P<.02), experienced disease symptoms more frequently (69.4% vs 100%; P<.001), and had lower viral load at first clinical presentation (median, 4.3 vs 0.0 log copies; P=.01). In multivariate analyses, low peak anti-HCV level (<93.5 od/co) was the only independent predictor for SVC; the hazard ratio compared with high anti-HCV levels (> or =93.5 od/co) was 2.62…
    The epidemiology of hepatitis A virus (HAV) infection is shifting from high to intermediate endemicity in Brazil, resulting in increased numbers of susceptible individuals and a greater potential for the emergence of outbreaks. Universal... more
    The epidemiology of hepatitis A virus (HAV) infection is shifting from high to intermediate endemicity in Brazil, resulting in increased numbers of susceptible individuals and a greater potential for the emergence of outbreaks. Universal vaccination against HAV has been recommended for children, but updated sero-epidemiological data are necessary to analyze the level of natural immunity and to identify candidates for preventive measures. In addition, more molecular studies are necessary to characterize the genotypes involved in HAV infections and outbreaks. Sera from 299 school children (5-15 years old) and 25 school staff members, collected during an outbreak of HAV at a rural public school in June 2000, were tested for IgM and total anti-HAV antibodies (ELISA). Viral RNA was amplified by RT-PCR from anti-HAV IgM-positive sera and from 19 fecal samples. Direct nucleotide sequencing of the VP1/2A region was carried out on 18 PCR-positive samples. Acute HAV infection was detected by anti-HAV IgM in 93/299 children and in 3/25 adult staff members. The prevalence of total anti-HAV antibodies in IgM-negative children under 5 years of age was only 10.5%. HAV-RNA was detected in 46% IgM-positive serum samples and in 16% stool samples. Sequence analysis showed that half the isolates belonged to subgenotype IA and the other half to IB. On the basis of these data, mass vaccination against HAV is recommended without prevaccination screening, especially for children before they enter school, since nearly 90% of the children under 5 years were susceptible. Molecular characterization indicated the endemic circulation of specific HAV strains belonging to subgenotypes IA and IB.