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Biomedical subjects

B Nalpas

Publications and source records attributed to B Nalpas.

At least 37 records · Page 2Linked to original sources
PubMed1998

Predictive factors for development of cirrhosis in parenterally acquired chronic hepatitis C: a comparison between immunocompetent and immunocompromised patients.

BACKGROUND/AIMS: The aim of this study was to evaluate the impact of the host immune status and of virological and environmental parameters on the development of cirrhosis during chronic hepatitis C virus infection. METHODS: Liver histology (cirrhosis or not, Knodell score) was evaluated according to age, sex, route and age of contamination, alcohol consumption and immune status in a large series of 553 HBsAg-negative patients (whose duration of hepatitis C virus infection could be precisely evaluated) divided into three groups: group 1 consisted of 462 immunocompetent subjects (46.1% intravenous drug users, 53.9% transfused), infected for a mean of 12.5+/-6.7 years, including 16.6% of alcohol abusers (>80 g/day); groups 2a and 2b consisted of 91 immunocompromised patients, 52 human immunodeficiency virus-coinfected patients corresponding to group 2a and 39 kidney recipients undergoing immunosuppressive therapy for group 2b, having been infected by hepatitis C virus for a mean of 12.6+/-5.3 and 11.5+/-5.3 years, respectively. RESULTS: Group 1: cirrhosis was present in 11.0% of group 1 patients and in 23.6% of immunocompetent patients with a duration of hepatitis C virus infection of 20 years or more. Forty-three percent of patients with cirrhosis and with hepatitis C virus infection for more than 20 years were alcohol abusers. The time taken to develop cirrhosis was 14+/-7 years in patients infected before the age of 40 years as compared to 8+/-5 years in those infected after 40 years (p<0.001). Groups 2a and 2b: cirrhosis was present in 19.8% of immunocompromised patients, a significantly higher rate than in immunocompetent patients (p<0.01). Alcohol abuse did not increase the risk of cirrhosis in this group. All patients but one were infected by hepatitis C virus before the age of 40 and the calculated time elapsed until the occurrence of cirrhosis was 12.4+/-5.5 years. In groups 1, 2a and 2b, there was no relation between histological severity, hepatitis C virus genotype and viral load. Four variables were independently associated with the occurrence of cirrhosis in the multivariate analysis: age over 40 at time of contamination (RR=9.3 in age range 40 to 59 and 91.2 in > or =60 years); long duration (> or =20 years) of hepatitis C virus infection (RR=15.4); alcohol consumption over 80 g/d (RR=2.9); and human immunodeficiency virus-coinfection (RR=2.6). CONCLUSIONS: Our study on a large series of well-characterized patients provides an accurate evaluation of the risk of cirrhosis in parenterally-contaminated immunocompetent hepatitis C virus-infected patients, with an overall figure of 11%. It also demonstrates the impact of the host immune status on the risk of severe histological lesions during chronic hepatitis C virus infection. It finally establishes the importance of age at the time of viral infection in the occurrence of cirrhosis, as well as the importance of alcohol consumption. Thus, at least following parenteral infection, both host-related and environmental cofactors play a major role in the severity of the liver lesions associated with hepatitis C virus infection.

Adult↗
PubMed1998

Retrospective analysis of the impact of HIV infection and alcohol use on chronic hepatitis C in a large cohort of drug users.

BACKGROUND/AIM: This retrospective study aimed to better define the respective biological and pathological impact of human immunodeficiency virus infection and chronic alcohol consumption on the course of hepatitis C virus infection in intravenous drug users. METHODS: Two hundred and ten consecutive anti-HCV positive intravenous drug users, among whom 60 were also anti-HIV positive, took part in the study at the University Hospital, Paris, France. RESULTS: The activity of aspartate aminotransferase and gamma-glutamyl transpeptidase was significantly increased in serum from anti-HIV positive patients. The mean hepatitis activity index was significantly higher in anti-HIV positive patients (p<0.05), among whom there was also a higher proportion of patients with cirrhosis as compared to anti-HIV negative patients (30.0 vs 15.3%, p<0.0001). Excessive alcohol drinking (recorded in around 35% of the patients, whatever their HIV status), as compared to non-excessive drinking, was more often associated with cirrhosis in anti-HIV negative (24.5 vs 11.3%, p<0.05) than in anti-HIV positive patients (30.4 vs 29.7%, not significant). In a multivariate analysis, HIV infection (relative risk 2.2, confidence interval 1.1-4.5) and excessive alcohol drinking (relative risk 1.9, confidence interval 1.0-3.9) were the variables independently associated with the risk of cirrhosis. CONCLUSION: Human immunodeficiency virus infection worsens the course of chronic hepatitis C in intravenous drug users. Excessive alcohol drinking also appears to be a crucial negative cofactor, and therefore alcohol withdrawal should be proposed as an integral part of the therapy.

Adult↗
PubMed1998

Hepatitis G virus infection in hepatitis C virus-positive patients co-infected or not with hepatitis B virus and/or human immunodeficiency virus.

This was a retrospective study to evaluate the prevalence and impact of hepatitis G virus (HGV) infection in hepatitis C virus (HCV)-positive drug addicts, according to the serological status of hepatitis B virus (HBV) and human immunodeficiency virus (HIV) coinfection. Two hundred and thirty-five randomly selected intravenous drug addicted patients (147 French, 88 Italian) were studied. All patients were positive for antibodies to HCV (anti-HCV). HGV RNA positivity was measured by reverse transcriptase-polymerase chain reaction (RT-PCR). Comparisons of HCV RNA positivity rate, and biological and histopathological variables, were made between HGV RNA-positive and negative patients, according to their HBV and HIV status. HGV prevalence was around 30% in both French and Italian groups. No clear association between HGV infection and a particular HCV genotype was observed. The rate of HCV RNA positivity did not differ between HGV-positive and HGV-negative patients after stratification for hepatitis B surface antigen (HBsAg) and HIV positivity. Histological severity of the underlying chronic hepatitis did not differ according to the HGV status; however, in HIV-positive HBsAg-negative patients, the hepatitis activity was moderately increased in HGV-positive patients. A striking negative influence of HBsAg positivity on HCV replication was observed in HIV-negative patients; an HCV RNA-positive rate of 25% was found in HBsAg-positive patients vs 86% in HBsAg-negative patients; similar significant results were observed in HIV-positive patients, although to a lesser extent. The underlying chronic hepatitis was significantly more severe in HBsAg-positive than in HBsAg-negative HIV-negative patients. Hence, HGV infection is highly prevalent in anti-HCV positive drug addicts but the co-infection with HCV does not seem to influence HCV replication nor to worsen the underlying chronic hepatitis, in HIV-negative patients at least. Reciprocal influence between HBV, HCV and HIV appears rather complex, HBsAg carriage seeming to exert per se a negative effect on HCV replication, particularly in HIV-negative patients, suggesting that interactions between hepatitis viruses should always be analysed in the light of HIV status.

Adult↗
PubMed1998

Medical practices regarding hepatitis C virus infection in Europe.

Six hundred and ninety-three European Association for the Study of the Liver (EASL) members, belonging to one of the 15 European Union (EU) member-states, were surveyed, through a standardized 45-item questionnaire, on their medical practices regarding hepatitis C virus (HCV) infection. The response rate was 45%, roughly similar in all the countries concerned. Responders were classified into three groups according to their geographical origin: North, Centre and South. A consensus existed with regard to the necessity of HCV screening in well-defined situations, such as history of blood transfusion, haemodialysis, haemophilia or intravenous drug addiction (90% of positive answers) while opinions substantially differed for vertical and nosocomial transmission of HCV. For the prevention of sexual and vertical transmission, opinions differed greatly: 22% were in favour of barrier methods for HCV-positive subjects while 34% were against; 49% allowed breast-feeding for babies born to HCV-positive mothers while 14% were against. Conversely, there was relative homogeneity in the issue of domestic prevention (70% in favour of precautions). Algorithms for prescription of virological tests were inhomogeneous (recombinant immunoblot assay was used by 60%; polymerase chain reaction was requested by 77% when alanine amino-transferase (ALT) was elevated vs 89% when normal): medical evaluation varied according to ALT values: liver biopsy and liver ultrasonography were carried out in 90 and 91% vs 40 and 70% for increased and normal ALT, respectively. Thirty per cent of respondents advised patients to stop alcohol consumption and 60% advised moderation. Two-thirds of the responders did not take into account histological severity and virological parameters before initiating antiviral therapy. Eighty per cent of the participants claimed that they administered interferon (IFN) for 12 months. For most of the items studied, there was a large variation, not only between the three groups, but also within each group. Ninety-two per cent of the responders claimed that they were well trained on HCV but they were rather critical of the quality of the information diffused (satisfaction rate: 45%). Altogether, our survey demonstrates that preventive and medical practices towards HCV are not homogeneous throughout the EU; this suggests the need for a European consensus conference in this regard.

Europe↗
PubMed1998

Gender, menstrual cycle, oral contraceptives and red blood cell deformability in healthy adult subjects.

Gender, menstrual cycle and oral contraceptives may have influence on mechanical properties of Red Blood Cell (RBC) and particularly on RBC deformability. So cell transit parameters have been assessed by filtration with the Cell Transit Analyser (CTA) for a large healthy adult population (seventy-nine males and one-hundred-fifteen females). The CTA provides the distribution of cell transit times of 5000 red blood cells, the mean transit time of the population and different percentiles such as p50, p75, p90 and p95. No effect of oral contraceptives was found. Nevertheless, influence of sex and menstrual cycle were demonstrated. A significant increase of the filtration parameters measured in the female population with respect to the male population and during menstruation, preovulation and post-ovulation periods was observed. During ovulation, the CTA parameters are comparable to the same parameters found in males.

Adult↗
PubMed1997

Hepatitis C virus genome complexity correlates with response to interferon therapy: a study in French patients with chronic hepatitis C.

Recent studies performed in Japan have suggested that hepatitis C virus (HCV) genome heterogeneity might be taken as a predictive virological parameter of response to interferon alfa (IFN-alpha) treatment. However, there is presently no information on the impact of this virological parameter in patients from Western countries infected by different HCV genotypes. We have investigated this issue by using amplification of HCV E2 hypervariable region 1, followed by single-strand conformation polymorphism assay (PCR-SSCP). We have studied 95 French patients infected with various genotypes and treated with IFN-alpha-2b. We analyzed the impact of the following parameters by univariate and multivariate analyses: HCV heterogeneity, HCV genotype, viral load, and liver histology in response to therapy. Age >40 years (P < .01), viral load >35 x 10(5) Eq/mL (P < .01), genotype 1 (P < .01), and a number of SSCP bands >3 (P < .001) were significantly associated with nonresponse or relapse; cirrhosis was associated with nonresponse. In multivariate analysis, three variables were independently associated with the absence of long-term response: SSCP bands >3, genotype 1, and viral load >35 x 10(5) with odds ratios of 19, 7.5, and 11.8, respectively. Our data establish the major importance of HCV genome heterogeneity in patients infected with both HCV types associated with low (genotype 1b) or high (genotype 3a) response to IFN-alpha.

Adult↗
PubMed1997

Spontaneous and iatrogenic spreading of liver-derived cells into peripheral blood of patients with primary liver cancer.

The prognosis for patients with primary liver cancer (PLC) often depends on tumor recurrence and the development of extrahepatic metastases, particularly after liver transplantation. We have developed a sensitive test to detect both spontaneous circulation of tumor cells and the spread of liver cells due to chemoembolization and alcoholization. Reverse-transcription polymerase chain reaction was used to search for cells expressing alpha-fetoprotein (AFP) messenger RNA in the peripheral blood of 84 patients with PLC and 102 controls (55 patients with chronic hepatitis and/or cirrhosis, 10 patients with benign liver tumors or liver metastases from intestinal cancers, and 37 healthy individuals). By spiking the blood of healthy volunteers with HepG2 cells, we assessed the sensitivity limit: one HepG2 cell mixed with 10(7) leukocytes. All 102 controls tested negative. In contrast, 28 patients (33.3%) with PLC tested positive. Positivity for the test was significantly associated with portal thrombosis, tumor size, intravascular tumor emboli, serum AFP level, and extrahepatic metastases. Patients were followed up for a mean period of 39 +/- 51 weeks: the probability of developing extrahepatic metastases was significantly higher in positive than in negative patients. Eighteen negative patients with PLC were tested before, 1 hour after, and 24 hours after locoregional therapy: 9 tested positive either 1 or 24 hours after alcoholization or chemoembolization. In conclusion, we have developed a highly specific and sensitive test to detect circulating tumor cells in patients with PLC. This test is likely to be clinically useful in evaluating the risk of developing extrahepatic metastases and the possibility of iatrogenic spreading of liver-derived, possibly tumorous, cells.

Female↗
PubMed1997

A comparative study between carbohydrate-deficient transferrin and gamma-glutamyltransferase for the diagnosis of excessive drinking in a liver unit.

AIM: To compare the efficacy of carbohydrate-deficient transferrin and gamma-glutamyltransferase for the diagnosis of excessive alcohol intake in patients admitted in a liver unit. METHODS: The 346 patients were divided into three groups of alcoholics: 57 patients (31 men, 26 women) with a normal liver, 77 patients (51 men, 26 women) with non-cirrhotic alcoholic liver disease, and 61 patients (43 men, 18 women) with alcoholic cirrhosis; and three groups of non-alcoholics: 35 abstainers (21 men, 14 women), and 58 healthy blood donors (26 men, 32 women), and 58 patients (32 men, 26 women) who had a non-alcoholic liver disease. Carbohydrate-deficient transferrin and gamma-glutamyltransferase were measured at admission using commercially available kits. RESULTS: Carbohydrate-deficient transferrin was more sensitive than gamma-glutamyltransferase in patients without alcoholic liver disease, in both men (85 vs 54%) and women (64 vs 36%). Carbohydrate-deficient transferrin sensitivity decreased slightly but not significantly according to the severity of the liver disease in men and women. The sensitivity of gamma-glutamyltransferase which was low in men and women without alcoholic liver disease, improved in groups with moderate or severe alcoholic liver disease: not less than 80% in men and up to 100% in women. The specificity of carbohydrate-deficient transferrin in patients with non-alcoholic liver disease was consistently higher than that of gamma-glutamyltransferase (80% vs 60%). CONCLUSIONS: In liver units, carbohydrate-deficient transferrin can help to identify excessive drinkers without liver disease with a higher efficacy than that of gamma-glutamyltransferase; carbohydrate-deficient transferrin can also be used to distinguish between alcoholics with moderate liver disease and patients with non-alcoholic liver diseases.

Adult↗
PubMed1997

Mutations in the nonstructural 5A region of hepatitis C virus and response of chronic hepatitis C to interferon alfa.

BACKGROUND & AIMS: Mutations in hepatitis C virus (HCV) nonstructural protein 5A (NS5A) may correlate with response to interferon in Japanese patients with chronic hepatitis C. The aim of this study was to examine whether these findings could be expanded to European patients infected with genotypes associated to low (1b) or high (3a) response rates. METHODS: Pretreatment serum samples of 66 patients with chronic HCV infection, 48 infected with genotype 1b and 18 with 3a, were analyzed. RESULTS: Among patients infected with genotype 3a, 1 of 7 long-term responders and none of 11 nonresponders showed NS5A amino acid mutations. Among patients infected with genotype 1b, all 7 long-term responders, but also 27 of 41 nonresponders, showed NS5A mutations. There was no correlation between number of mutations and response to therapy. In 10 patients, sequences obtained before and after treatment were compared and failed to show any change. Serum HCV RNA levels did not differ between patients with and without mutations in NS5A sequence. CONCLUSIONS: No significant correlation was found in patients infected with genotypes 1b or 3a between NS5A sequence and response to interferon alfa. NS5A mutations do not correlate with viral load. Changes in this region were not found during interferon alfa treatment.

Adult↗
PubMed1996

Interactions between alcohol and hepatitis viruses in the liver.

There is a high frequency of hepatitis B virus (HBV) and hepatitis C virus (HCV) infections among individuals with alcoholic liver disease (ALD) and alcohol-associated hepatocellular carcinoma (HCC), suggesting that these viruses are implicated in the pathogenesis of these diseases. Alcohol may act synergistically by promoting the development and progression of liver disease. The interactions of alcohol with infected hepatocytes and with antiviral immunity may result in altered patterns of virus gene expression and replication, making diagnosis difficult in some cases of ALD and HCC. The potential association of ALD and alcoholic HCC with serologically negative virus variants raises major difficulties in the epidemiologic assessment of cause and effect, providing major challenges for the future.

Animals↗
PubMed1995

Hepatitis C virus type 1b (II) infection in France and Italy. Collaborative Study Group.

OBJECTIVE: To analyze the distribution of hepatitis C virus (HCV) genotypes among patients positive for antibody to HCV (anti-HCV) according to age, severity of liver disease, and duration of infection; to investigate the influence of HCV genotypes on response to interferon-alpha therapy; and to study HCV viremia levels in relation to genotypes and severity of liver disease. DESIGN: Cross-sectional study. SETTING: 3 university hospitals and 2 research units. PATIENTS: 3 groups of French and Italian patients with chronic HCV infection and detectable serum HCV RNA: Group 1 included 35 patients with hepatocellular carcinoma; group 2, 71 patients with cirrhosis who did not have hepatocellular carcinoma; and group 3, 114 patients with chronic active hepatitis. 106 of the patients with chronic hepatitis or cirrhosis were treated with interferon-alpha (3 MU subcutaneously 3 times/wk for > or = 6 months). MEASUREMENTS: Genotyping by polymerase chain reaction with capsid-specific primers; serum HCV RNA by branched DNA (bDNA) signal amplification. RESULTS: Hepatitis C virus genotype 1b (II) was the most prevalent genotype (61.8%). In a univariate analysis, it was associated with older age (< 40 years, 47.4%; > or = 60 years, 80.4%; P = 0.001), longer duration of disease (< or = 10 years, 40.4%; > or = 20 years, 86.7%; P = 0.005), and cirrhosis with or without hepatocellular carcinoma (78.4% compared with 53.8% for chronic hepatitis; P < 0.001). Viremia levels did not differ between patients infected with HCV type 1b (II) and those infected with other HCV genotypes. Patients with HCV type 1b (II) responded to interferon-alpha therapy significantly less than did patients with other HCV genotypes (P = 0.01). In a multivariate analysis, age and cirrhosis were independently associated with HCV genotype 1b (II). Genotype and HCV viremia level were independent predictors of response to interferon-alpha therapy. CONCLUSIONS: The prevalence of HCV genotypes in French and Italian patients has been changing; the prevalence of HCV type 1b (II) infection has progressively decreased, although it still accounts for most HCV-related cirrhosis and hepatocellular carcinoma. High HCV viremia levels and HCV genotype type 1b (II) are independent predictors for poor response to interferon-alpha therapy and should be considered in the management of patients with HCV infection.

Adult↗
PubMed1995

Serum secretory IgA and secretory component in patients with non-cirrhotic alcoholic liver diseases.

Elevated levels of secretory IgA in serum have been demonstrated in several liver dysfunctions such as hepatic cytolysis and cholestasis. However, these possible alterations at an early stage of liver diseases have not yet been investigated. We studied a cohort of chronic alcoholic patients without cirrhosis in order to assess the changes in serum secretory IgA and other forms of secretory component, the split product of the polymeric Ig-receptor of epithelial cells. The possible diagnostic value of these measurements in the assessment of alcoholic disease was compared to that of serum gamma-glutamyl transpeptidase activity. Serum levels of secretory IgA and IgM and free secretory component, were quantified by an enzyme-linked immunosorbent assay in 71 patients with chronic alcoholic liver disease without cirrhosis and in 45 healthy controls. Patients were divided into two groups according to the severity of the liver abnormalities. In addition, the reversibility of serum secretory IgA, IgM and free secretory component abnormalities after alcohol withdrawal was evaluated in 15 patients. Serum levels of the three molecular forms of secretory component were significantly higher than those measured in control subjects, both in the whole population of patients and in the two groups of alcoholic patients without cirrhosis. In all groups, serum secretory IgA levels were correlated to free secretory component but not to total IgA levels. Serum secretory IgA levels were as discriminative as gammaglutamyl transferase activity in distinguishing between chronic alcoholic patients without cirrhosis and non-alcoholic subjects. The abnormalities of serum secretory IgA concentrations were reversible after alcohol withdrawal.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Effects of ethanol on hepatitis B virus Pre-S/S gene expression in the human hepatocellular carcinoma derived HEP G2 hepatitis B DNA positive cell line.

BACKGROUND/AIMS: Among the reported interactions between ethanol and hepatitis B virus (HBV), studies of transgenic mice have suggested an effect of ethanol on the secretion of viral envelope proteins. METHODS: We further investigated these interactions in vitro by determining HBs antigen levels and performing northern blots of viral mRNA in human cell culture (HepG2 HBV positive cells) exposed for 3 to 12 days to various concentrations of ethanol. RESULTS: In cultures exposed to 200 mM ethanol, HBs antigen concentrations increased in the medium (p < 0.05) after 3 days as Pre-S1 and Pre-S2 protein concentrations. This increase was not specific, as albumin and ferritin increased in the same proportions. Ethanol also increased the HBs antigen concentration in the cells (p < 0.05), whereas levels of viral mRNA encoding surface proteins were unaffected. CONCLUSIONS: These findings show that short-term ethanol exposure in vitro can induce HBs antigen overexpression via a post-transcriptional mechanism.

Acetaldehyde↗
PubMed1995

Serum hepatitis C virus (HCV) RNA: a reliable tool for evaluating HCV-related liver disease in anti-HCV-positive blood donors with persistently normal alanine aminotransferase values.

BACKGROUND: The significance of hepatitis C virus (HCV) antibodies in blood donors with persistently normal alanine aminotransferase (ALT) levels requires evaluation. STUDY DESIGN AND METHODS: The serum and the liver were assayed for HCV RNA. Liver histology was analyzed in 14 HCV-positive subjects who had repeatedly normal ALT values over a follow-up period of at least 3 months. RESULTS: HCV RNA was not detected in liver and serum, and liver histology showed minimal changes in more than one-half of the subjects (8/14), even if third-generation recombinant immunoblot assay was positive; this demonstrated that HCV can be eradicated spontaneously. Moderately histopathological liver lesions were usually found in HCV RNA-positive subjects (6/14), but one subject had active disease that required interferon therapy; this shows that chronic hepatitis may be present in HCV-positive individuals despite repeatedly normal transaminase values. HCV genotypes other than 1b (II) were usually identified, and the presence or absence of serum and liver HCV RNA correlated completely in all 14 patients. CONCLUSION: Serum HCV RNA should be assayed in those HCV-positive donors having repeatedly normal transaminase activity; if it is positive, indicating an ongoing HCV infection, a liver biopsy should be performed to measure the degree of the liver disease and determine the appropriate antiviral therapy.

Adult↗
PubMed1995

Clinical impact of drug addiction in alcoholics.

Careful interviewing of alcoholics who wish to undergo alcohol withdrawal programmes reveals that some are past intravenous drug abusers. As these two potentially hepatotoxic types of substance abuse could cause liver disease or influence its clinical course, we studied biological, histological and virological features in 26 alcoholics with a past history of intravenous (i.v.) drug abuse, compared with paired controls (alcoholics without i.v. drug abuse). There were no differences with regard to routine liver test results. In contrast, the former drug abusers had a significantly higher prevalence of serum markers of hepatitis C (76.9%) and hepatitis B viruses (76.9%) than the other patients (16.7 and 12.5%, respectively). Eight patients, all of whom were HBs Ag negative, were positive for serum HBV-DNA; three were former drug abusers and five were not, giving an overall prevalence of HBV markers in the two groups of 80.8 and 25%, respectively. Two former drug abusers had anti-HIV antibodies and one had anti-hepatitis delta virus antibodies. Ten of the 17 former drug abusers who underwent liver biopsy had histological signs of viral infection. These data underline the need for careful interviews of alcoholic patients, together with serological tests for viral infections and histological analysis of the liver, as some will have liver-damaging viral diseases and may be candidates for anti-viral (i.e. interferon) treatment.

Adult↗
PubMed1995

[Cost-benefit analysis of vaccinal prevention of hepatitis B policy].

Morbidity and mortality related to hepatitis B (VHB) induce heavy costs even in low endemia countries as France. Recent changes in patterns of virus transmission (increasing heterosexual contamination) lead to discuss the opportunity of re-evaluation of current VHB vaccine policies aiming primarily at most exposed populations (patients under dialysis, hospital workers, infants born to VHB+ mothers). Using cost-benefit methodology, in a context where epidemiological and economical pertinent data are quite rare, this article evaluates different strategies ("no vaccination", "universal vaccination" and "vaccination after screening") for four different populations with contrasted exposure (French general population, young men adults, homosexual men and intravenous drug users). The cost-benefit ratios indicate that thresholds are, for low-risk populations, very far from usually accepted values attributed to epidemiological and economical parameters. If vaccine is administrated to young men adults, the cost-per-hepatitis saved relative to "no vaccination" is 36,000 F. For high-risk exposure groups, vaccination may be considered cost-benefit for attack rates near (homosexual men) or greater (drug users) than that observed; optimal strategy could be obtained if drug users are screened and vaccined. This is the result of combination of relatively low incidence of VHB and variability of medical course and chronic sequalae. Consequently, if universal vaccination has to be chosen, it would mean that the implicit value attributed to the prevention of one hepatitis is very high.

Adolescent↗