Seropositivity for hepatitis B virus, vaccination coverage, and vaccine response in dentists from Campo Grande, Mato Grosso do Sul, Brazil

This study investigated the seropositivity for hepatitis B virus (HBV), the vaccination index, and the vaccine response index in dentists from Campo Grande, MS. Blood samples from 474 dentists (63.7 percent women and 36.3 percent men), with a mean age of 38.5 ± 10.5 years were analyzed by enzyme-linked immunosorbent assay to detect the serological markers: HBsAg, anti-HBs, and anti-HBc. The HBsAg positive samples were tested for anti-HBc IgM, HBeAg, and anti-HBe. A total of 51 (10.8 percent) dentists showed seropositivity for HBV. Three (0.6 percent) were HBsAg/anti-HBc/anti-HBe positive, 43 (9.1 percent) were anti-HBc/anti-HBs positive, and 5 (1.1 percent) had only anti-HBc. Viral DNA was detected by polymerase chain reaction in 9 (17.6 percent) out of 51 HBV seropositive samples. A vaccination index of 96.6 percent (458/474) was observed, although 73.1 percent (335/458)completed the three-dose schedule. Excluding 46 HBV seropositive individuals from 458 that reported vaccination, 412 were analyzed for vaccine response index. It was observed that 74.5 percent (307/412) were anti-HBs positive; this percentage increased to 79.1 percent when three doses were administered. The results showed a high vaccination index and a good rate of vaccine response; however, the failure in completing the three-dose schedule and the occurrence of HBV infection reinforce the need for more effective prevention strategies.

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.

Infecções e reinfecções por Rotavirus A: genotipagem e implicações vacinais / Rotavirus A infections and reinfections: genotyping and vaccine implications

OBJETIVOS: Identificar Rotavirus A em crianças com diarréia aguda, determinando os genótipos G e P prevalentes e avaliar a ocorrência de infecções e reinfecções por rotavírus do grupo A em crianças. MÉTODOS: Foram estudadas, prospectivamente, crianças com doença diarréica aguda e identificação de Rotavirus A em Goiânia (GO), durante o período de julho de 2000 a outubro de 2002. Igual número de crianças, pareadas por idade e sexo, que não apresentavam diarréia aguda e sem identificação de rotavírus nas amostras fecais à admissão ao estudo, representou o grupo controle. Foram analisadas a ocorrência de infecções ou reinfecções sintomáticas ou assintomáticas por rotavírus durante o período de estudo, durante um ano de seguimento em ambos os grupos. Todas as amostras positivas foram submetidas a genotipagem G e P através das reações de RT-PCR e Nested PCR. RESULTADOS: A infecção por rotavírus ocorreu em 37,2 por cento (77 de 207 amostras fecais) das crianças com diarréia aguda durante o período do estudo. Os genótipos G e P identificados foram, simultaneamente: G1 (62,3 por cento), G9 (34,4 por cento) e G4 (3,3 por cento) e P[8] (59 por cento), P[6] (7,7 por cento), P[6]+P[8] (23,1 por cento), P[4]+P[8] (7,7 por cento) e P[4]+P[6] (2,6 por cento). As associações de genótipos G e P identificados durante o estudo foram: G1P[8] (77,8 por cento), G9P[8] (11,1 por cento), G4P[8] (5,6 por cento) e G1P[6] (5,6 por cento). Não houve reinfecção por rotavírus nos pacientes do grupo Rotavirus A (+) durante o período de seguimento, enquanto duas crianças do grupo controle apresentaram infecções sintomáticas por rotavírus durante o mesmo período. CONCLUSÕES: Os genótipos G e P predominantes correspondem aos das candidatas atuais à vacina contra rotavírus. Não houve reinfecção por rotavírus pelo período de um ano em relação a todos os genótipos identificados.

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

Hepatitis B virus infection profile in Central Brazilian hemodialysis population

A hepatite B tem sido uma grande ameaca aos pacientes de hemodialise. Para investigar o perfil da infeccao pelo virus da hepatite B (VHB) na populacao de hemodialise de Goiania - Brasil Central, 282 pacientes foram estudados. A prevalencia de marcadores do VHB (AgHBs, anti-HBc e anti-HBs) foi de 56,7 por cento (IC 95 por cento: 51,1 - 62,7) variando de 33,3 por cento a 77,7 por cento entre as unidades de dialise. O VHB-DNA foi detectado nas amostras AgHBs positivas em 67,6 por cento e 88,2 por cento, nas AgHBs e AgHBe em 91,3 por cento e 100 por cento, e nas AgHBe e anti-HBe e soro reativas em 18,2 por cento e 63,6 por cento por hibridizacao e PCR, respectivamente. O tempo de tratamento hemodialitico mostrou-se estatisticamente associado a soropositividade ao VHB. Somente 10 por cento dos pacientes relataram vacinacao para a hepatite B. Assim, uma prevalencia elevada para infeccao pelo VHB nesta populacao e o risco aumentado do tempo de tratamento hemodialitico sugerem a transmissao ambiental deste virus...