Seroepidemiology of hepatitis B virus infection and high rate of response to hepatitis B virus Butang®vaccine in adolescents from low income families in Central Brazil

In order to evaluate the seroepidemiology and response to Butang® vaccine in adolescents from low income families in Central Brazil, blood samples of 664 adolescents were tested for hepatitis B surface antigen (HBsAg), hepatitis B core antibody (anti-HBc), and hepatitis B surface antibody (anti-HBs) markers, and multiple logistical regression analysis was carried out to determine variables associated with hepatitis B virus (HBV) infection markers. further, three 20 µg butang® vaccine doses were offered to all susceptible individuals (n = 304). Among those who accepted them (n = 182), the seroresponse was evaluated in 170 individuals by quantitative anti-HBs. an overall hbv prevalence of 5.9 percent was found: four adolescents were HBsAg positive, 24 were anti-HBc, anti-HBs-reactive, and 11 were anti-HBc only. The analyse of risk factors showed that age 16-19 years, place of birth outside Goiás, school B and body piercing were statistically associated with HBV infection markers (p < 0.05). All 170 adolescents responded to butang®, and a geometric mean titer (gmt) of 4344 mui/ml was obtained. these results reinforce the importance of hepatitis b vaccine in adolescents despite of the hbv regional endemicity, and suggest that three doses of 20 µg of the butang® should guarantee protective anti-hbs levels to individuals at a critical time for hepatitis b acquiring such as latter adolescence and adulthood.

Decline of hepatitis C infection in hemodialysis patients in Central Brazil: a ten years of surveillance

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 percent, however a b decrease in positivity was detected between 1999 and 2002 (37.8 vs 16.5 percent) when the measures were fully implemented. Also, a decrease of the anti-HCV accumulated incidence in cohorts of susceptible individuals during 1993-2002 (71 percent), 1996-2002 (34.2 percent), and 1999-2002 (11.7 percent) 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, ratifying the importance of public health strategies for control and prevention of hepatitis C in the hemodialysis units.

GB virus C/hepatitis G virus infection in dialysis patients and kidney transplant recipients in central Brazil

In order to investigate the prevalence of GB virus C (GBV-C)/hepatitis G virus (HGV) infection in dialysis patients and kidney transplant recipients in Central Brazil and also to analyze the virus genotypes distribution, a total of 123 patients including 98 on hemodialysis, 13 on continuous ambulatory peritoneal dialysis treatment, and 12 who received kidney transplantation were interviewed in one unit of dialysis treatment in Goiânia city. Blood samples were collected and serum samples tested for GBV-C/HGV RNA by polymerase chain reaction. Genotypes were determined by restriction fragment length polymorphism (RFLP) analysis. Eighteen samples were GBV-C/HGV RNA-positive, resulting in an overall prevalence of 14.6 percent (95 percent CI: 9.2-21.7). A high positivity for GBV-C/HGV RNA was observed in patients who had received kidney transplant (16.7 percent), followed by those on hemodialysis (15.3 percent), and peritoneal dialysis (7.7 percent). RFLP analysis revealed the presence of genotypes 1, 2, and 3 of GBV-C/HGV; more precisely, 9 (50 percent) samples were found belonging to the 2b subtype, 4 (22 percent) to the 2a subtype, 3 (17 percent) to genotype 1, and 2 (11 percent) to genotype 3. The present data indicate an intermediate prevalence of GBV-C/HGV infection among dialysis patients and kidney transplant recipients in Central Brazil. Genotype 2 (subtype 2b) seems to be the most prevalent GBV-C/HGV genotype in our region.

Infecção pelo vírus da hepatite B em hemofílicos em Goiás: soroprevalência, fatores de risco associados e resposta vacinal / Seroprevalence, vaccination response and risk factors for hepatitis B virus infection in hemophiliacs in Goiás

Objetivando determinar a prevalência da infecção pelo vírus da hepatite B (HBV) em hemofílicos em Goiás, analisar os fatores de risco associados e avaliar a resposta vacinal contra hepatite B, 102 pacientes foram entrevistados e amostras sangüíneas coletadas para detecção dos seguintes marcadores sorológicos: HBsAg, anti-HBs e anti-HBc. Uma prevalência global de 43,7 por cento (IC 95 por cento: 33,5-54,2) para infecção pelo HBV foi encontrada. A análise multivariada dos fatores de risco mostrou que o número de episódios transfusionais e sorologia positiva para o vírus da hepatite C estiveram significantemente associados à positividade ao HBV. Foram identificados 49 (48,1 por cento) hemofílicos susceptíveis a esta infecção, sendo imunizados 30 pacientes com a vacina recombinante Euvax-B. Destes, 28 (93,3 por cento) indivíduos apresentaram títulos de anti-HBs maiores que 10 UI/L, o que mostra uma boa resposta à vacina. Os achados deste estudo ressaltam a importância das medidas de controle e prevenção da hepatite B nesta população.

In order to study the prevalence and risk factors for hepatitis Bin hemophiliacs in Goiás, 102 patients were interviewed andblood samples collected and screened for the following serologicalmarkers: HBsAg, anti-HBs and anti-HBc. An overall prevalenceof 43.7% (95% IC: 33.5-54.2) was found to hepatitis B virus(HBV) infection. Multivariate analysis of risk factors showedthat the number of transfusions and positive serology for hepatitisC virus were significantly associated with HBV positivity. Therewere 48 (48.1%) susceptible patients for this infection, of whom30 were immunized with the Euvax-B vaccine. Among them, 28(93.3%) individuals developed anti-HBs titers higher than 10IU/L. Thus, a good response was observed in the studiedpopulation. The findings of this study emphasize the importanceof strategies of control and prevention of hepatitis B in thispopulation.

Hepatitis B and C in the hemodialysis unit of Tocantins, Brazil: serological and molecular profiles

A survey was conducted in the hemodialysis population of the state of Tocantins, Brazil, aiming to assess the prevalence of hepatitis B virus (HBV) and hepatitis C virus (HCV) infections, to analyze associated risk factors, and also to investigate these viruses genotypes distribution. During January and March 2001, all patients (n = 100) were interviewed at the unique dialysis unit in Tocantins. Blood samples were collected and serum samples were screened for HBV serological markers. Hepatitis B surface antigen positive samples were tested for HBV DNA. All samples were also tested for anti-HCV antibodies and HCV RNA. An overall prevalence of 45 percent was found for HBV infection (4 percent were HBsAg/anti-HBc positive, 2 percent were anti-HBc only and 39 percent had anti-HBc/anti-HBs markers). Concerning HCV infection, anti-HCV and HCV RNA were detected in 13 percent and 14 percent of the subjects, respectively. Three patients were HCV RNA positive and anti-HCV negative, resulting in an overall HCV prevalence of 16 percent. Univariate analysis of risk factors showed that only shift and length of time on hemodialysis were associated with HBV and HCV positivity, respectively. Among the four HBsAg-positive samples, HBV DNA was detected in three of them, which were identified as genotype A by restriction fragment length polymorphism (RFLP) analysis. All 14 HCV RNA-positive samples were genotyped by INNO-LiPA. Genotypes 1a and 3a were found in 85 percent and 15 percent, respectively. The present data show low HBsAg and HCV prevalence rates. The risk factors associated with HBV and HCV positivity suggest that nosocomial transmission may influence in spreading these viruses in the dialysis unit studied

Prevalence and genotypes of GB Virus C/Hepatitis G virus among blood donors in Central Brazil

A survey was conducted in a blood donor population of Central Brazil aiming to investigate the prevalence of GB virus C (GBV-C)/hepatitis G virus (HGV) infection and also to analyze the virus genotypes distribution. A total of 241 voluntary blood donors were interviewed at the State Blood Bank in Goiânia, State of Goiás, Brazil. Blood samples were collected and serum samples tested for GBV-C/HGV RNA by polymerase chain reaction. Genotypes were determined by restriction fragment length polymorphism (RFLP) analysis. Seventeen samples were GBV-C/HGV RNA-positive, resulting in a prevalence of 7.1 percent (95 percent CI: 4.2-11.1). A significant trend of GBV-C/HGV RNA positivity in relation to age was observed, with the highest prevalence in donors between 29-39 years old. Ten infected individuals were characterized by reporting parenteral (30 percent), sexual (18 percent), both (6 percent) and intrafamiliar (6 percent) transmission. However, 7 (40 percent) GBV-C/HGV RNA-positive donors did not mention any potential transmission route. RFLP analysis revealed the presence of genotypes 1 and 2 of GBV-C/HGV; more precisely, 10 (58.9 percent) samples were found belonging to the 2b subtype, 4 (23.5 percent) to the 2a subtype, and 3 (17.6 percent) to genotype 1. The present data indicate an intermediate endemicity of GBV-C/HGV infection among this blood donor population, and a predominant circulation of genotype 2 (subtype 2b) in Central Brazil

Hepatitis C prevalence and risk factors in hemodialysis patients in Central Brazil: a survey by polymerase chain reaction and serological methods

An hemodialysis population in Central Brazil was screened by polymerase chain reaction (PCR) and serological methods to assess the prevalence of hepatitis C virus (HCV) infection and to investigate associated risk factors. All hemodialysis patients (n=428) were interviewed in eight dialysis units in GoiÔnia city. Blood samples were collected and serum samples screened for anti-HCV antibodies by an enzyme-linked immunosorbent assay (ELISA). Positive samples were retested for confirmation with a line immunoassay (LIA). All samples were also tested for HCV RNA by the PCR. An overall prevalence of 46.7 percent (CI 95 percent: 42-51.5) was found, ranging from 20.7 percent (CI 95 percent: 8.8-38.1) to 90.4 percent (CI 95 percent: 79.9-96.4) depending on the dialysis unit. Of the 428 patients, 185 were found to be seropositive by ELISA, and 167 were confirmed positive by LIA, resulting in an anti-HCV prevalence of 39 percent. A total of 131 patients were HCV RNA-positive. HCV viremia was present in 63.5 percent of the anti-HCV-positive patients and in 10.3 percent of the anti-HCV-negative patients. Univariate analysis of risk factors showed that the number of previous blood transfusions, transfusion of blood before mandatory screening for anti-HCV, length of time on hemodialysis, and treatment in multiple units were associated with HCV positivity. However, multivariate analysis revealed that blood transfusion before screening for anti-HCV and length of time on hemodialysis were significantly associated with HCV infection in this population. These data suggest that nosocomial transmission may play a role in the spread of HCV in the dialysis units studied. In addition to anti-HCV screening, HCV RNA detection is necessary for the diagnosis of HCV infection in hemodialysis patients