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1.
A prospective incidence study was used to estimate the effect on transmission of hepatitis B virus (HBV) in England and Wales of maximising uptake of HBV vaccination in patients at risk attending genitourinary medicine (GUM) clinics or any medical services. Laboratory based surveillance in 1993 gave an incidence of acute symptomatic hepatitis B of 1 case per 100,000 population. Transmission through sexual intercourse was twice as common as through injecting drug use. Less than 20% of patients with acute HBV infection had attended a GUM clinic before their illness, but 42% had had access to other medical services where vaccination could have been offered routinely. Sixty per cent of patients' sexual partners and 37% of other members of their household had been offered vaccination. Compared with universal infant or pre-adolescent vaccination, extending the current selective policy to all who attend GUM clinics or any medical services would have a limited impact on the incidence of HBV, particularly as uptake of three doses of vaccine in adults is likely to be low.  相似文献   

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Acute hepatitis A is a major public health problem in developed countries, and because a large proportion of patients with acute hepatitis A do not have any identifiable risk factors, current practice of targeting the high-risk groups for vaccination against hepatitis A virus (HAV) is unlikely to have a significant impact on the overall incidence of acute hepatitis A. No economic analysis of strategies of mass immunization against HAV is available. Three different strategies of immunization against HAV using commercially available inactivated vaccine were compared in a Markov model analysis of a cohort of 2-year-old healthy children in a developed country. In strategy I, universal vaccination was pursued. In strategy II, children were initially screened for antibody and, if susceptible, they were vaccinated. In strategy III, no vaccination was offered. Cost per person and quality adjusted life-years (QALY) gained in each strategy were the outcome measures compared. The baseline analysis showed that strategy II is more cost-effective than strategy I, with marginal cost-effectiveness ratios of $7,267. 67 and $12,833.34, respectively, compared with a strategy of no intervention. Sensitivity analysis showed that if the cost of the two-dose vaccine could be reduced to less than $57, the strategy of universal vaccination would be the preferred immunization strategy. Different strategies of mass immunization against HAV in the developed countries are cost-effective by current standards of health care interventions and should be considered for incorporation into current childhood immunization programs.  相似文献   

4.
AIM: In this cost-effectiveness study 4 different vaccination strategies against hepatitis B in children and adolescents are evaluated and compared with the situation without immunization. EXAMINATION: Projections are made for the population of the today's adolescents underage 15 and the newborns of the next 30 years. The number of avoided hepatitis B virus (HBV) infections and the cases of disease as well as the costs associated with treatment and vaccination are determined. The course of incidence of the hepatitis B virus is observed for different age groups. RESULTS: Compared to the situation without any vaccination against hepatitis B, a decrease of the remaining infections of at least 18,900 up to 46,600 could be expected during the next 30 years. The treatment costs for the remaining cases of disease could be reduced by 0.4 up to 1.6 billions DM. The remaining expenditures for treatment and vaccination would be limited to 2.3 up to 3.4 billions DM. The net costs of a vaccination are determined as about 14,200 up to 63,000 DM per avoided case of infection. Considering the commonly accepted number of unreported cases of hepatitis B as to be the 5- to 10 fold of the known incidence, all of the 4 compared vaccination strategies will be cost-effective and associated with net savings of about 5,900 up to 36,400 DM per avoided case of hepatitis B virus infection during 30 years. The epidemiological situation will be positive influenced by such a mass vaccination. The minimization of incidence is shown for the different age groups. CONCLUSION: Considering these economical arguments, first the vaccination of all adolescents between age 11 to 15 and second the vaccination of all children/adolescents between age 0 to 15 are the preferable strategies. The immunization of all children/adolescents between age 0 to 15 is the most effective strategy from an epidemiological point of view.  相似文献   

5.
The hepatitis G virus is a newly discovered flavivirus that has been linked to acute and chronic hepatitis of unknown cause. We determined the prevalence of hepatitis G virus infection in 179 selected patients undergoing liver transplantation at three centers participating in the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) Liver Transplantation Database. Pretransplantation and posttransplantation specimens were tested for hepatitis G virus RNA by polymerase chain reaction. Before transplantation, 9 of 38 (24%) patients with fulminant hepatic failure, 9 of 62 (15%) with cryptogenic cirrhosis, 3 of 35 (9%) with cholestatic liver disease, and 5 of 44 (11%) with chronic hepatitis C were positive for hepatitis G virus RNA (P = .27). Patients with and without viral RNA were similar in clinical features, liver test abnormalities, and survival after transplantation. Posttransplantation serum specimens were tested from 73 patients; 9 of 11 (82%) who were positive for viral RNA before transplantation remained positive, but 35 of 62 (56%) patients who were initially negative became positive after transplantation, a rate consistent with that predicted from the number of blood products administered. Only 5% of de novo HGV infections could be attributed to preexisting hepatitis G virus RNA in the donor. Comparison of patients with and without hepatitis G virus infection showed no difference in incidence of hepatitis after transplantation. Thus, hepatitis G virus infection was present in 15% of patients before and appeared de novo in half of patients after liver transplantation. Although hepatitis G virus infection was not associated with poor outcome, the frequency of this infection after transplantation calls for further long-term evaluation.  相似文献   

6.
Active immunization against hepatitis B virus infection was carried out in 162 patients with acute lymphoblastic leukemia attending the Outpatient Department at Tata Memorial Hospital. Recombinant DNA vaccine was given in three doses at 0, 1 and 2 months followed by a booster 1 year after the first dose. Antibodies to hepatitis B surface antigen could be detected in 19.7% of patients following vaccination. Of these only 10.5% had titers in the protective range. Immunosuppression induced by both disease and treatment appears to diminish responsiveness to vaccination. Passive active prophylaxis with both vaccine and immunoglobulin may be a more effective alternative in these patients.  相似文献   

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The development of molecular biology techniques has enabled us to clone the genetic sequence of three new hepatitis viruses, namely, hepatitis C virus, hepatitis E virus and hepatitis G, or GBV-C virus in the last decade. Hepatitis C virus (HCV) is now known to account for the majority of the parenterally transmitted non-A, non-B hepatitis and hepatitis E virus (HEV) is the major cause of the epidemics of enterally transmitted non-A, non-B hepatitis in the less developed countries, mainly through contaminated water supplies. While 80% of those who were infected with HCV will become chronic carriers, there is no known chronic carrier state for HEV. To date, 6 major genotypes of HCV were identified, with various variants of genotype 6 described in Southeast Asia. In Singapore, the majority of our chronic hepatitis C patients are infected with genotype 1. The seroprevalence rate of HEV is 10% to 14% in Singapore. This probably reflects our suboptimal sanitary condition in the past rather than a reflection of a currently high HEV infection rate in our population. However, local cases of acute hepatitis E have been reported. As for the most recently cloned hepatitis G virus, its aetiologic role in the remaining cases of non-A, non-B hepatitis is still unclear. Some preliminary evidence suggests that it may be just an innocent bystander with limited pathogenicity and it certainly cannot account for all the remaining cases of non A-E hepatitis. Hence, the search for yet another hepatitis virus continues.  相似文献   

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BACKGROUND: The G6PD deficiency is a red cell enzymopathy very frequent in certain Mediterranean countries. In Menorca (Balearic Islands), a relatively high incidence of favism carried us to study the prevalence of this alteration, taking advantage of the "Campaign for detection of heterozygous beta-thalassaemia to prevent the homozygous beta-thalassaemia" that we make annually. METHODS: We studied a total of 1139 school boys between 13-14 years old for three consecutive school years. We used the methylene blue as screening test and the deficiency of G6PD was confirmed with enzymatic quantification in the haemolysate. We also analysed the clinical manifestations and studied the relatives. RESULTS: We have confirmed 11 cases of G6PD deficiency (prevalence of 9.7/1000), all of them native of the island. The clinical manifestations were: in 6 cases (54.5%) no clinical manifestations were found, 5 cases (45.4%) had presented neonatal jaundice and 2 cases (18.2%) had suffered a favism crisis. The study of relatives permitted us to analyse 26 additional samples (17 women and 9 men), detecting in 8 of them (4 women and 4 men) the enzymopathy . CONCLUSIONS: The prevalence of G6PD deficiency in Menorca is one of the highest in Spain. Most of the carriers are asymptomatic, the most important clinical manifestations being the neonatal jaundice and favism. The screening test used is efficient for unmistakable hemizygotes detection.  相似文献   

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OBJECTIVE: To compare seroconversion using hepatitis B vaccine between hemodialysis (HD) and peritoneal dialysis (PD) patients. DESIGN: Data on PD patients vaccinated were collected retrospectively for the period 1992 to 1995. The data on HD patients were collected prospectively from 1991 to 1994. SETTING: A university outpatient dialysis center. PARTICIPANTS: All adult patients who received all four doses of hepatitis B vaccine while on dialysis were included (47 PD and 50 HD patients). INTERVENTION: Recombinant hepatitis B vaccine (Engerix), 40 micrograms IM was administered at 0, 1, 2, and 6 months. MAIN OUTCOME MEASURE: Seroconversion was measured after completion of the vaccination series. RESULTS: 74% of the HD patients seroconverted compared to 53% of PD patients (p = 0.03). Older, heavier patients compared to all the other patients had a lower seroconversion rate in both the HD patients (55% vs. 78 %) and PD patients (38% vs. 59%) (p = 0.03). CONCLUSION: The seroconversion rate to recombinant hepatitis B vaccine is lower in patients on PD than on HD for unclear reasons. Further studies are required to determine the etiology of this difference.  相似文献   

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OBJECTIVE: To assess baseline health status of a medical school employee population and to assess this population's acceptance of vaccination and other interventions to reduce risk of disease transmission. DESIGN: A retrospective review of an employee health records database for a 4-year period. SETTING: A large, urban university hospital. PARTICIPANTS: 5,007 employees screened by employee health for immunity to vaccine-preventable illnesses and tuberculosis. RESULTS: 9.4% of the employees had positive tuberculin skin tests, with a conversion rate of 6.4% for those who had negative tests within the previous 2 years. Two individuals were identified who had active pulmonary tuberculosis. Fewer than 10% of the individuals for whom isoniazid chemoprophylaxis was recommended completed the 6 months of therapy. Most clinical employees (96.1%) did not have a history of prior hepatitis B virus (HBV) infection or immunization, but 77% of them subsequently completed the vaccination series. Most employees with a negative history for infection with or immunization against rubella, rubeola, and varicella had serological evidence of immunity (90.2%, 97.9%, and 87.2%, respectively). CONCLUSIONS: Review of aggregate employee health databases may assist individuals who must establish strategies for prevention of occupational illness and disease transmission in this specialized setting. While many employees at risk for HBV complete the vaccination series, strategies for improving this rate could be helpful. Substantial work is needed to analyze reasons why so few individuals for whom isoniazid chemoprophylaxis is recommended complete the therapy, and strategies tailored to the impediments identified should be implemented.  相似文献   

13.
BACKGROUND/AIMS: Patients with chronic hepatitis C are often coinfected with the new identified Flaviviridae-like agent, termed hepatitis G virus (HGV). The aim of the study was to investigate the responsiveness of hepatitis G virus to interferon alpha and to evaluate whether a hepatitis G virus coinfection negatively influences the outcome of treatment in chronic hepatitis C. METHODS: One hundred and fifteen patients with histologically proven chronic hepatitis C were treated with interferon alpha and investigated for the presence of hepatitis G virus coinfection by nested polymerase chain reaction with primers from the helicase region of hepatitis G virus. All patients received at least 3 MU (range 3-6) interferon alpha thrice weekly for at least 6 months (mean 8, range 6-12). Polymerase chain reaction products of seven pre- and post-treatment hepatitis G virus positive patients were directly sequenced for identification of sequence variability during the follow-up. RESULTS: Eighteen (16%) patients were coinfected with hepatitis G virus. Although nine (50%) of these patients became HGV RNA negative during interferon alpha therapy, only three patients (17%) remained HGV RNA negative at the end of follow-up (mean 24 months). The rate of sustained response of chronic hepatitis C was not significantly different between patients with hepatitis C virus infection and HCV/HGV coinfection (19% vs 28%). Severity of liver disease as determined by alanine aminotransferase levels, histology and hepatitis C virus viremia was not significantly different in patients with hepatitis C virus or HCV/HGV coinfection. Sequence analysis of the helicase region revealed that our isolates all belonged to the hepatitis G virus and not to the GBV-C like genotype. No amino acid exchanges during the observation period of up to 48 months were observed, indicating that this region is highly conserved. CONCLUSIONS: The responsiveness of hepatitis G virus to interferon alpha in chronic HCV/HGV coinfected patients is similar to that observed in chronic hepatitis C. Hepatitis G virus coinfection seems not to interfere with the efficacy of interferon alpha treatment in patients with chronic hepatitis C.  相似文献   

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BACKGROUND: There are few reports in Mexico on the prevalence of infection by virus D. OBJECTIVE: The aim of the present study was to study the hepatitis D virus infection prevalence in patients entering to the University Hospital. METHODS: Seventy three HBsAg positive patients sera were studied. There were 38 patients with acute hepatitis, 28 patients with chronic liver disease and 7 were asymptomatic HBsAg carriers. Serological markers for hepatitis viruses B, D and C were detected by means of ELISA test (Abbott). RESULTS: Anti-HDV was detected in 3 cases (4%). The first two cases were men with acute hepatitis B. Both had a coinfection by viruses B and D, however IgM anticore could not be demonstrated in the first case, this patient developed hepatic cirrhosis within 13 months, in addition he had a concurrent infection by hepatitis C virus with a positive second generation ELISA antibody. The second case recovered from the acute hepatitis. The third case was a female nurse with acute hepatitis and a coinfection by viruses B and D who recovered from the acute attack. Antibody to hepatitis C was present in 3 out of 22 patients with chronic liver disease (13.6%), one of them having an hepatocellular carcinoma. CONCLUSIONS: Our results coincide with the previously reported low incidence of hepatitis D and represent the first report in Mexico of concurrent infections by viruses B-C and B-D-C.  相似文献   

15.
Liver involvement was retrospectively evaluated in 137 patients with murine typhus. Fifteen (10.9%) were jaundiced. One patient had been subjected to cholecystectomy after misdiagnosis of acute cholecystitis. Serum aminotransferase levels were abnormal in 48/52 measurements, and there were elevations of > 5-fold in 14 patients. Liver biopsies and/or necropsies from four jaundiced patients showed portal tract and sinusoidal infiltrates, cloudy swelling/and necrosis of the hepatocytes and occasional pseudogranuloma formation. There were striking mitoses even in the early stage, suggesting rapid hepatocellular regeneration. Haemolytic diseases (G6PD deficiency or haemoglobinopathies), alcoholism, and a second infection probably also contributed to the pathogenesis of jaundice in murine typhus. This rickettsiosis should be included among differential diagnoses of acute hepatitis in patients exposed to areas endemic for Rickettsia typhi.  相似文献   

16.
OBJECTIVE: To determine the hepatitis B vaccination status of juvenile offenders in a custodial setting, their perceived risk of hepatitis B infection, and factors influencing vaccine uptake. DESIGN: 130 males aged 14-17 years resident at the Melbourne Juvenile Justice Centre for at least one week between mid-January and mid-December 1996 were invited to participate; 90 (69%) completed a doctor-administered questionnaire, and blood for serological testing was obtained from 83 of these participants. MAIN OUTCOME MEASURES: Whether hepatitis B vaccine had been offered; whether hepatitis B vaccine had been given; the presence of antibodies to hepatitis B and C; risk factors and self-perceived risk of hepatitis B. RESULTS: About a quarter of participants (22/83) had protective levels of antibody to hepatitis B surface antigen (anti-HBs). Forty (44%) participants reported having been offered hepatitis B vaccine; they were more likely to be vaccinated and have protective levels of anti-HBs. Perceived risk for bloodborne virus infection was low, although two-thirds of participants were at high risk of hepatitis B infection. On serological testing, 6.4% (5/78) were positive for antibody to hepatitis B core antigen (anti-HBc), and a further 2.6% (2) had equivocal antibody levels. Of the 71 who were negative for anti-HBc, 51 (71.8%) were negative for anti-HBs. CONCLUSIONS: The targeted hepatitis B vaccination program has not adequately protected this group at high lifetime risk of hepatitis B. Failure to deliver vaccine may reflect lack of contact with healthcare services, oversight in offering vaccine and reluctance of youth to participate in preventive healthcare measures, often through not seeing themselves to be at risk. Universal approaches to vaccination may be more successful in vaccinating this group.  相似文献   

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Hepatitis A virus infection is major cause of acute hepatitis in the United States, accounting for approximately 75,000 cases of clinical illness each year. These infections occur among persons in every age group and are associated with a variety of exposures related to fecal-oral transmission. Recently, the U.S. Food and Drug Administration approved licensure of two inactivated hepatitis A vaccines. Both vaccines are highly immunogenic and have been licensed in pediatric and adult formulations. The prevention of hepatitis A virus infection is directly related to many aspects of family practice, and family physicians may see patients in a variety of settings that warrant administration of hepatitis A vaccine. Groups for whom vaccination is currently recommended include international travelers, children in communities with high rates of hepatitis A virus infection, men who have sex with men, Illicit drug users, patients with chronic liver disease and persons with clotting factor disorders.  相似文献   

18.
It was recently reported that mutations in the precore and core promoter region of hepatitis B virus (HBV) are associated with fulminant hepatitis. The aim of this study was to investigate the association of mutations in the precore and core promoter region of HBV with fulminant and severe acute hepatitis. We studied Japanese patients with acute HBV infection, including seven patients with fulminant hepatitis, 12 with severe acute hepatitis and 41 with acute self-limited hepatitis. The presence of HBV mutants was examined by using a point mutation assay to detect a G to A transition at position 1896 in the precore region and an A to T transition at position 1762 and a G to A transition at position 1764 in the core promoter region. Significant differences in the proportion of mutations in the precore or core promoter region were present between patients with fulminant hepatitis and self-limited acute hepatitis (7/7 (100%) vs 4/41 (9.8%), P<0.01) and between severe acute hepatitis and self-limited acute hepatitis (6/12 (50.0%) vs 4/41 (9.8%), P<0.01). The frequency of mutation increased proportionately with the severity of disease in patients with acute HBV infection. Fulminant hepatitis B in Japan is closely associated with mutations in the core promoter and precore gene of HBV. Point mutation assays for HBV precore and core promoter analysis may be useful to predict the outcome of liver disease in patients with acute HBV infection.  相似文献   

19.
Hepatitis B virus (HBV) accounted for 24% to 54% of the reported acute viral hepatitis cases in Singapore from 1982 to 1996. The prevalence of HBV infection, as indicated by the presence of markers of HBV, increased from 9.3% in children below 5 years of age to 54.6% in adults above 55 years. The overall hepatitis B surface antigen (HBsAg) prevalence was 5.7% for males and 3.4% for females, with the highest rate among the Chinese. About 39% of the HBsAg carriers were hepatitis B 'e' antigen positive. The main mode of transmission during the first year of life was perinatal, with 43% of the babies born to HBsAg-positive mothers developing the carrier state. Horizontal transmission within the infected household was significantly associated with sharing of personal and household articles. Based on the findings of seroprevalence surveys in various population groups and clinical trials on the safety, immunogenicity and efficacy of various doses and schedules with the plasma-based and yeast-derived hepatitis B vaccines in newborn babies, a national childhood hepatitis B vaccination programme was formulated and implemented in phases, starting with babies born to carrier mothers on 1 October 1985 and finally extending to all newborns on 1 September 1987. The hepatitis B prevention and control programme has been successful. During the period 1994 to 1996, more than 90% of children completed the full schedule of immunisation by below one year of age, and 85% had evidence of vaccination at school entry at age six. Follow-up of 2 cohorts of vaccinated children showed that perinatal transmission has been reduced by 80% to 100%. Horizontal transmission has also declined through other public health measures. The efficacy of the hepatitis B vaccine and the adequacy of reduced doses in the long-term protection of chronic carrier state have been shown in children and adults. The incidence of acute hepatitis B has declined from 10.4 per 100,000 in 1985 to 4.8 per 100,000 in 1996. There is a noticeable reduction in HBsAg prevalence in selected population (school children, national servicemen and antenatal women). The age-standardised incidence rate of primary liver cancer among males had also dropped from 27.8 per 100,000 per year during 1978 to 1982 to 19.0 per 100,000 per year during 1988 to 1992.  相似文献   

20.
Currently, six distinct types of hepatitis virus have been identified: A, B, C, D, E, and G. Hepatitis A virus infection does not cause a chronic carrier state, and perinatal transmission is extremely uncommon. Hepatitis B can be transmitted perinatally, but immunization of the newborn with hepatitis B immune globulin and hepatitis B vaccine markedly reduces the risk of neonatal infection. Hepatitis D virus is dependent on coinfection with the hepatitis B virus for replication. Immunoprophylaxis against hepatitis B also is effective against hepatitis D. Hepatitis C virus is primarily transmitted by the parenteral route and is particularly likely to cause chronic liver disease. Perinatal transmission of hepatitis C principally occurs in women who have high titers of HCV-RNA or who are coinfected with human immunodeficiency virus. At this time, no immunoprophylaxis for hepatitis C is available. Hepatitis G, a recently described organism, is related to hepatitis C. Its clinical significance remains undetermined. Hepatitis E is transmitted in a manner similar to hepatitis A. Perinatal transmission is unusual, but maternal disease is often severe.  相似文献   

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