The possibility of detecting acute infection and immunity using body fluids that are easier to collect than blood, mainly in children, would facilitate the investigation and follow-up of outbreaks of hepatitis A (HAV). Our study was carried out to evaluate the detection of anti-HAV IgM, IgA and total antibodies in saliva using serum samples as reference. Forty three paired serum and saliva samples were analyzed. From this total, 24 samples were obtained from children and 1 from one adult during the course of acute hepatitis A; an additional 18 samples were obtained from health professionals from Adolfo Lutz Institute. The sensitivity to detect anti-HAV IgM was 100% (95%CI: 79.1 to 100.0%), employing saliva as clinical samples. In detecting anti-HAV IgA, the sensitivity was 80. 8% (95%CI: 60.0 to 92.7%) and for the total antibodies was 82.1% (95%CI: 62.4 to 93.2%). The specificity was 100% for each. The rate of agreement was high comparing the results of serum and saliva samples for detecting HAV antibodies. We conclude that saliva is an acceptable alternative specimen for diagnosing acute hepatitis A infection, and for screening individuals to receive hepatitis A vaccine or immunoglobulin.

The seroprevalence of anti-hepatitis E virus (HEV) antibodies was investigated by enzyme immunoassay in 205 volunteer blood donors, 214 women who attended a center for anonymous testing for human immunodeficiency virus (HIV) infection, and 170 hospital employees in Campinas, a city in southeastern Brazil. The prevalence of anti-HEV antibodies ranged from 2.6% (3 of 117) in health care professionals to 17.7% (38 of 214) in women who considered themselves at risk for HIV. The prevalence of anti-HEV antibodies in health care professionals was not significantly different from that in healthy blood donors (3.0%, 5 of 165) and blood donors with raised alanine aminotransferase levels (7.5%, 3 of 40). The prevalence of anti-HEV antibodies (13.2%, 7 of 53) in cleaning service workers at a University hospital was similar to that among women at risk for HIV infection. These results suggest that HEV is circulating in southeastern Brazil and that low socioeconomic status is an important risk factor for HEV infection in this region.Hepatitis E virus (HEV) is considered the main etiologic agent of enterically transmitted non-A, non-B hepatitis (ET-NANBH) and occurs in epidemics or sporadically. ET-NANBH, once thought to be a disease confined to developing countries, is now recognized to have a wider geographical distribution (12,33). Epidemics have been related to contaminated water supplies, as fecal-oral transmission is the major route of transmission (29). The symptoms of ET-NANBH are similar to those of hepatitis A, although it affects primarily young adult populations already immune to hepatitis A virus (HAV). HEV is well recognized as a cause of fulminant hepatic failure in areas where it is endemic (23), particularly in pregnant women who contract it in the third trimester (10). In developed countries, sporadic cases have been identified among travelers from areas where it is endemic and HEV has been implicated in some community-acquired cases of NANBH in the United States and other western countries (12).Until recently, the diagnosis of ET-NANBH was based on serology after the exclusion of other viral hepatitis. In 1990, the isolation of a partial cDNA clone from HEV (22) led to the identification of type-common immunodominant epitopes and the development of diagnostic serological assays for the detection of antibodies to recombinant HEV antigens (4).The prevalence of HEV infection among blood donors in developed countries ranges from 0.4 to 3.9% (4,14,15). An association between HEV and hepatitis C virus infections has been reported, suggesting similar or overlapping routes of transmission (21). In addition, a higher prevalence of antibodies to HEV has been reported among patients undergoing chronic hemodialysis (9), suggesting that this virus is also spread by the parenteral route. Homosexual men also have a high prevalence of HEV infection (15), and the possibility of sexual transmission cannot be neglected. Few studies have addressed the prevalence of HEV infection in Brazil because diagnostic tests for this illnes...

J Bras Patol Med Lab • v. 43 • n. 5 • p. 313-318 • outubro 2007

Drosophila melanogaster S2 cells were transfected with a plasmid vector (pAcHBsAgHy) containing the S gene, coding for the hepatitis B virus surface antigen (HBsAg), under control of the constitutive drosophila actin promoter (pAc), and the hygromycin B (Hy) selection gene. The vector was introduced into Schneider 2 (S2) Drosophila cells by DNA transfection and a cell population (S2AcHBsAgHy) was selected by its resistance to hygromycin B. The pAcHBsAgHy vector integrated in transfected S2 cell genome and approximately 1,000 copies per cell were found in a higher HBsAg producer cell subpopulation. The HBsAg production varied in different subpopulations, but did not when a given subpopulation was cultivated in different culture flasks. Higher HBsAg expression was found in S2AcHBsAgHy cells cultivated in Insect Xpress medium (13.5 lg/1E7 cells) and SFX medium (7 lg/1E7 cells) in comparison to SF900II medium (0.6 lg/1E7 cells). An increase of HBsAg was observed in culture maintained under hygromycin selection pressure. Data presented in the paper show that S2AcHBsAgHy cells produce efficiently the HBsAg which is mainly found in the cell supernatant, suggesting that HBsAg is secreted from the cells. The data also show that our approach using the Drosophila expression system is suitable for the preparation of other viral protein preparation.

In this study, we evaluated the hepatitis B virus (HBV) genotype distribution and HBV genomic mutations among a group of human immunodeficiency virus-HBV co-infected patients from an AIDS outpatient clinic in São Paulo. HBV serological markers were detected by commercially available enzyme immunoassay kits. HBV DNA was detected using in-house nested polymerase chain reaction and quantified by Cobas Amplicor. HBV genotypes and mutations in the basal core promoter (BCP)/pre-core/core regions and surface/polymerase genes were determined by sequencing. Among the 59 patients included in this study, 55 reported prior use of lamivudine (LAM) or tenofovir. HBV DNA was detected in 16/22 patients, with a genotype distribution of A (n = 12,75%), G (n = 2,13%), D (n = 1,6%) and F (n = 1,6%). The sequence data of the two patients infected with genotype G strongly suggested co-infection with genotype A. In 10 patients with viremia, LAM-resistance mutations in the polymerase gene (rtL180M + rtM204V and rtV173L + rtL180M + rtM204V) were found, accompanied by changes in the envelope gene (sI195M, sW196L and sI195M/sE164D). Mutations in the BCP and pre-core regions were identified in four patients. In conclusion, genotype G, which is rarely seen in Brazil, was observed in the group of patients included in our study. A high prevalence of mutations associated with LAM-resistance and mutations associated with anti-HBs resistance were also found among these patients

The aim of this study was to determine the prevalence and the incidence of hepatitis B virus (HBV) among haemodialysis (HD) subjects and to evaluate whether testing for serological markers at the time of admission is suitable for HBV screening in this population. One hundred twenty-three patients belonging to two HD centres from SãoPaulo, Brazil, were tested prospectively. HBV DNA was detected by polymerase chain reaction (PCR) and HBsAg was detected in 3.3% of patients. These authors were in agreement that 54% of patients were either positive for HBsAg, HBV DNA or both. The aim of this study was to determine the prevalence and the incidence of HBV among HD patients and to evaluate whether testing for serological markers at the time of admission is suitable for HBV screening in this population.All patients (n = 123) undergoing treatment in two HD centres from March 1997-April 1998 were included in this study. The study protocol was submitted and approved by the Ethical Committee of Adolfo Lutz Institute and an informed consent was obtained from each patient. These facilities were considered to be representative of local (São Paulo, Brazil) standard HD services. Both units were comparable in terms of the budget per subject, presence of an isolated area for HBV and HCV patients, recommendation of HBV vaccination for patients and staff and isolation of HBsAg-positive patients to the last shift of the HBV room. These HD centres had standard conditions as determined by Brazilian competent organs and by the CDC guidelines, including isolation of HBsAg-positive patients in a separate room and assignment of staff members to HBsAg-positive patients, but not to HBV-susceptible patients during the same shift, as well as assignment of a supply tray to each patient (CDC 2001, MS 2004.HD patients had previously received four doses of 40 µg of Engerix™ B, administered intramuscularly at zero, one, two and six months. Once a year, anti-HBs is quantified and one dose of vaccine is administered, if necessary. Patients had 10 mL of blood drawn from arterial-venous fistula just before the HD procedure, at the time of admission and on a monthly basis. Therefore, a total of 1,476 serum samples were obtained and separated into the following three aliquots: serological tests, PCR and reconfirmation, if necessary. Samples were stored at -20°C in a separate freezer.The first and the last samples from each patient were tested for HBV DNA using DNA extraction and nested PCR (core fragment) techniques, as previously described (Kaneko et al. 1989). All 1,476 samples were tested for HBsAg, total anti-HBc and anti-HBs antibodies using commercially available ELISA kits (Hepanostika™ Uni-

A hepatite B é doença de graves consequências quando adquirida no período neonatal. No entanto, a identificação das gestantes, com risco de transmitirem a infecção a seus filhos, pode prevenir essas consequências através da imunização, passiva e ativa, dos bebês logo após o nascimento. Foram estudadas 477 gestantes de primeira consulta atendidas no período de abril a outubro de 1988 nos oito Centros de Saúde da rede estadual que abrangem o subdistrito do Butantan, região oeste do município de São Paulo, considerada carente de infra-estrutura básica. As 477 amostras de soro foram ensaiadas quanto à presença do marcador anti-HBc total, que permite detectar os casos assintomáticos, crônicos e em fase de convalescença. As 44 (9,2%) gestantes positivas para esse marcador foram ensaiadas para os marcadores anti-HBs e HbsAg. Dessas 44 amostras, 2 (0,4%) foram positivas para o HBsAg e 37 (7,7%) positivas para anti-HBs. Do universo de 477 gestantes, 47 apresentaram no inquérito a que foram submetidas respostas indicativas de fatores de risco para hepatite, mas apenas 8 (17,0%) delas faziam parte do grupo de gestantes anti-HBc positivas, 2 delas HBsAg positivas

The hepatitis B virus surface antigen (HBsAg) gene, under control of the inducible mouse metallothionein I gene promoter, was inserted in an expression vector based on the Epstein-Barr virus (EBV). This vector was introduced into human cells by DNA transfection and clones were selected for their resistance to hygromycin B. The recombinant EBV vector replicates efficiently as an episome in human cells and approximately six copies per cell were found in one clone of hygromycin-B-resistant cells. These cells produce high levels of HBsAg in the presence of metals. The protein is mainly found in the cell medium, suggesting that the HBsAg is secreted from the cells.