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1.
Outbreak of Hepatitis B among injecting drug users in Denmark.   总被引:2,自引:0,他引:2  
BACKGROUND: The incidence of hepatitis B is low in Denmark, but injecting drug users (IDUs) remains a high-risk group for this infection. OBJECTIVES: The aim of the study was to describe a hepatitis B outbreak among IDUs by comparing existing registers. Additionally, we wanted to analyze the genetic variation of the hepatitis B virus involved in the outbreak. STUDY DESIGN: In the County of Funen, registers of laboratory diagnosis, hospital records and reports from clinicians to the Medical Officer of Health (MOH) were compared between 1992 and 1998. HBsAg positive sera recovered from the epidemic were sequenced and compared to known HBV strains. RESULTS: We identified 648 cases of hepatitis B of which 51% (332) were acute infections. The laboratory database identified 96% (319/332) of these, 45% (150/332) were admitted to hospital and 38% (127/332) were reported to public health. By capture-recapture analysis based on MOH reports and hospital records the estimated total number of acute cases were 334 (95% C.I. 283-385). We sequenced 75 HBsAg positive samples and identified two very similar strains of genotype D (serotype ayw3) among IDUs involved in the outbreak. CONCLUSIONS: The current surveillance system did not detect the majority of acute hepatitis B cases in County of Funen. We suggest laboratory-based surveillance of hepatitis B to be implemented at a national level as this may identify new outbreaks faster and more complete than the current surveillance system.  相似文献   

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3.
Five patients with acute hepatitis B and four with fulminant hepatitis B were selected for sequencing of the precore/core gene of the virus strains. Furthermore, identical sequencing was done with the HBV of the infectious sources, i.e., the sexual partner in eight cases and a natural child (chronic carrier) infecting the mother in one case. Of the subjects responsible for the infection, four were healthy HBV carriers, three suffered from chronic hepatitis B, and one from acute and one from fulminant hepatitis B. The nucleotide sequences of HBV from both the patients and the implicated sources of infection exhibited perfect identity of the precore region and perfect or high identity of the core region. The completely or nearly identical strain of virus seemed to proliferate successively in the patients following the transmission from the infecting individuals regardless of sequence variations and infectious status. In two cases a peculiar pattern of infection and disease was found: In one married couple the husband, during the incubation period of acute hepatitis B, infected his wife, who developed fulminant hepatitis. In another married couple, both partners ultimately developed fulminant hepatitis (the wife being the source of the infection). © 1994 Wiiey-Liss, Inc.  相似文献   

4.
Occult hepatitis B is defined by the presence of hepatitis B virus (HBV) DNA in the serum in absence of hepatitis B surface antigen (HBsAg). Studies were conducted to screen for occult HBV infection among family members of HBV carriers, incidentally detected positive for HBV infection with a view to assess the pattern of virus transmission among them. Nested PCR assay, employing independent sets of primers to surface and core genes, was used for detection of HBV DNA in serum samples from 28 index cases with asymptomatic HBV infection, and in serum samples from 72 HBsAg negative/anti-HBc positive family members. HBV DNA was detected in 15 HBsAg negative family members of 10 HBsAg positive index patients and was studied in detail. Direct sequencing of S gene region of 25 isolates (10 index cases and 15 contacts) and phylogenetic analysis with data base sequences revealed that genotypes A, C, and D and subtype adw2, adr, and ayw3 were present among them. Evidence of transmission from outside family sources was found in addition to intrafamilial transmission among individuals with occult infection. Mutations in the major hydrophilic loop (MHL) of the S gene region were also detected, including the 'vaccine escape' mutation G145R in three cases. Although majority of the occult infection was associated with low viral load, 3/15 (20%) cases were with higher viral load and potential infectivity. These cases are especially notable in diagnostic, blood banking, and transplantation services.  相似文献   

5.
BACKGROUND: The Rosenheim report, published in 1972, was aimed at decreasing the transmission of hepatitis B virus (HBV) in the renal unit. A review in 1996, revealed the non-compliance of some centres with the guidance to vaccinate individuals against HBV. OBJECTIVES: To describe two events of acute hepatitis B virus (HBV) infection within 9 weeks in individuals attending the renal unit and the steps taken to prevent further transmission. STUDY DESIGN: Serological and molecular testing was carried out on the two individuals with acute HBV and other HBV carriers in the unit. Epidemiological information was collected along with information on HBV vaccination and HBsAg screening. RESULTS: There were 15 known HBV carriers in the unit. HBV genotype E was transmitted from a carrier to patient 1 when they were in the same ward. Transmission to patient 2 occurred when he followed patient 1 on the theatre list. Breaks in infection control were identified and steps were taken to prevent further transmission events. CONCLUSIONS: Breaks in infection control procedures were rectified. No further transmission of HBV was identified. This highlights the need for vigilance regarding infection control practices in the renal unit setting.  相似文献   

6.
OBJECTIVE: To estimate the prevalence of HIV and hepatitis C virus (HCV) and hepatitis B virus (HBV) coinfections and current risk behaviors among HIV-positive and -negative injection drug users (IDUs) in Chennai, India. METHODS: Cross-sectional analysis of a convenience sample of 912 IDUs recruited between March 2004 and April 2005. Specimens were tested for HIV, HBV, and HCV. Adjusted prevalence ratios (PRs) were estimated using Poisson regression with robust variance estimates. RESULTS: The prevalence of HIV, hepatitis B surface antigen, and anti-HCV were 29.8%, 11.1%, and 62.1%, respectively. Among HIV-infected IDUs, prevalence of coinfection with anti-HCV and hepatitis B surface antigen/anti-HCV were 86% and 9.2%, respectively. In multivariate analysis, injecting at a dealer's place (PR: 1.57) and duration of injection drug use >or=11 years (PR: 3.02) were positively associated with prevalent HIV infection. Contrastingly, alcohol consumption >or=1 per week (PR: 0.55) was negatively associated with HIV. HIV-positive IDUs were as or more likely compared with HIV-negative IDUs to report recent high-risk injection-related behaviors. CONCLUSIONS: There is a high burden of HIV, HCV, and HBV among IDUs that needs to be addressed by improving access to therapies for these infections; furthermore, preventive measures are urgently needed to prevent further spread of HIV, HBV, and HCV in this vulnerable population.  相似文献   

7.
Hepatitis B virus (HBV), with a G-to-A point mutation at nucleotide 83 in the precore region (mutant HBV83), accounts for most cases of hepatitis B e antigen (HBeAg)-defective HBV. However, it is still not clear how mutant HBV83 is associated with HBe seroconversion. Twenty-six HBeAgpositive patients with chronic hepatitis B who received oral prednisolone (30 mg/day) for 3 weeks were studied to clarify the prevalence of mutant HBV83 during the treatment using polymerase chain reaction with a restriction fragment length polymorphism assay. Twelve (46%) patients seroconverted to anti-HBe 1 year after treatment, whereas 14 (54%) did not. The proportion of mutant HBV83 to whole HBV remained unchanged in both groups during an acute exacerbation induced by withdrawal of corticosteroids. Among 12 anti-HBe-0seroconverted patients, five (56%) of nine patients with only wild-type HBV at baseline developed detectable levels of mutant HBV83 while all three patients with a mixed viral population of wild-type HBV and mu tant HBV83 at baseline developed a higher pro portion of mutant HBV83 one year after treat ment. In contrast, these changes were observed in only one (14%) of seven who failed to seroconvert. The results indicate that a flare-up of hepa titis precedes emergence or selection of mutant HBV83, followed by HBe seroconversion in patients with chronic hepatitis B. © 1995 WiIey-Liss, Inc.  相似文献   

8.
To gain insight into the spread of hepatitis B among various risk groups in Amsterdam a 6-year (1992-1997) retrospective DNA sequencing study was carried out on isolates from stored sera from reported primary cases of acute hepatitis B infection. Cases were classified according to risk behavior, as determined in interviews. Of the available serum, a selected region of hepatitis B-virus-DNA was amplified and sequenced. The nucleotide alignments were subjected to phylogenetic tree analysis. When nucleotide alignments were subjected to phylogenetic analysis, the strains of 54 isolates, 26% of the 204 reported primary cases, clustered in five genotypes: A, C, D, E, and F. In genotype A, a cluster related to men having sex with men was identified. In genotype D, two subclusters could be identified: one was related to injecting drug use and another was related to the Moroccan population in Amsterdam. The remaining strains showed a high genetic variability within three different genotypes: F, E, and C. Of the 14 identical isolates in the "homosexual men cluster," one was isolated from a female heterosexual. Of the 14 identical strains in the "drug users strain," six were from non-drug using heterosexual active individuals. In the cluster of twelve isolates related to hepatitis B-endemic areas, probable modes of transmission were varied. Sequence analysis provides important insight into the spread of hepatitis B among various high-risk groups. The analysis indicates that the prevention strategy in The Netherlands fails to stop transmission of hepatitis B from persistently infected individuals originating from hepatitis B endemic countries.  相似文献   

9.
Vertical transmission from mother to child, the main route of chronic hepatitis B virus (HBV) infection in the East Asia, is considered one of the most important predictors for the response to antiviral therapies as well as its complications such as cirrhosis and hepatocellular carcinoma. Therefore, it is critical in both etiologic and prognostic aspects to confirm whether or not chronic HBV infection is acquired vertically. This study investigated whether mother-to-child infection could be proved by the phylogenetic analyses of HBV pre-S/S genes ever since several decades have elapsed in mother-child pairs with presumed vertical transmission. The pre-S and S regions of HBVs were compared and analyzed phylogenetically in a total of 36 adults (18 mother-child pairs) with chronic HBV infection. All of the isolates of HBV were genotype C and serotype adr. The divergence between mothers and offsprings was 0 to 1.5%. Phylogenetic trees revealed that 17 of 18 pairs (94%) with presumed vertical transmission were grouped into the same cluster. Vertical transmission from mother to child could be strongly suggested even in adults with a history of several decades of HBV infection using the phylogenetic analyses of pre-S and S genes.

Graphical Abstract

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10.
To gain insight into hepatitis B virus (HBV) transmission in the Netherlands, epidemiological data and sera were collected from reported cases of acute HBV infections in the Netherlands in 2004. Cases were classified according to mode of transmission. A fragment of the S-gene of HBV (648 bp) was amplified, sequenced, and subjected to phylogenetic analysis. Of the 291 acute HBV cases reported in 2004, 158 (54%) were available for genotyping. Phylogenetic analysis identified 6 genotypes: A (64%), B (3%), C (3%), D (21%), E (5%) and F (5%). Of HBV infected men having sex with men, 86% were infected with genotype A, accounting for 43% of all patients infected with this genotype. There were only three reported cases of injecting drug use of which one was available for sequencing (genotype A). Unlike the genotype A cluster, sequences within the genotype B-E clusters were heterogenic. Within genotype F, several isolates had identical sequences, but patients could not be epidemiologically linked. Sexual transmission, particularly by men having sex with men was the most important transmission route for HBV. Injecting drug use plays a minor role. Genotype A is predominant in the Netherlands, especially among men having sex with men. In addition to imported strains, there seems to be a pool of related but non-identical strains circulating among chronic carriers in the migrant population, from which occasionally new patients are infected, primarily by heterosexual transmission.  相似文献   

11.
BACKGROUND: The virological and clinical impact of hepatitis C virus (HCV) superinfection in chronic hepatitis B virus (HBV) carriers has been poorly characterized. OBJECTIVE: To evaluate the viral interaction, clinical presentation and course of the disease in four HBsAg/HBV-DNA positive chronic hepatitis patients who developed acute HCV infection. STUDY DESIGN: To evaluate clinical, virological and laboratory data for at least 6 months from the onset of acute HCV infection in patients with chronic HBV infection. RESULTS: Three patients with acute HCV infection had a normal clinical course, but the remaining patient had severe disease with ascites and a marked decrease in prothrombin activity. In all cases, plasma HBV-DNA, which had been detectable prior to the HCV infection, was no longer detectable when the acute HCV infection occurred. The inhibition exerted by HCV on HBV-DNA persisted throughout the follow-up period in three patients, but was temporary in the one patient who experienced an acute exacerbation of chronic HBV infection. HCV-RNA became persistently undetectable in two patients and reduced to low levels in the other two. CONCLUSIONS: Acute HCV infection in the four HBV chronic carriers was characterized by a reciprocal inhibition of HBV-HCV genomes and, in one case, by a severe course of disease.  相似文献   

12.
35型庚型肝炎临床及酶学变化观察   总被引:3,自引:1,他引:3  
For the purpose of making sure the clinical significance of hepatitis G virus, RT-nested PCR was applied to detect HGV RNA in 165 hepatitis patients, which included 24 acute hepatitis, 78 chronic hepatitis, 18 hepatitic cirrhosis, 4 hepatocellularcarcinom and 41 HBV and HCV carriers. The results showed that the infection of HGV existed in all kinds of hepatitis patients. Among the acute hepatitis 12.5% (3/24) was HGV RNA positive. 19 (24.4%) cases were HGV RNA positive in chronic hepatitis, among which 4 cases were simply HGV RNA positive (5.13%). The serum ALT level in 3 cases of simple acute HGV patients was between 488 +/- 65 U/L, the value of AST between 452 +/- 71 U/L, the TBiL at about 77.1 +/- 14.3 mumol/L. All these showed that only HGV infection could lead to acute hepatitis. The rising enzyme dropped to normal about a month later in acute hepatitis while HGV RNA would remain. The problem whether HGV infection is caused by simple acute and chronic hepatitis infection is under investigation.  相似文献   

13.
Hepatitis B virus genotypes are associated with transmission pattern, virological and clinical features and outcome of the chronic infection course. HBV genotypes other than Genotype F (HBV/F) are considered a reflection of human migration into South America. A total of 487 individuals in Bolivia, including Japanese immigrants (n=287) and natives (n=200), were screened for HBV serological markers. Overall 22/487 (4.5%) of the subjects were positive for HBsAg, 217/487 (44.5%) for anti-HBc and 162/487 (33.3%) for anti-HBs. Genotypes were determinable in 22 cases by EIA, followed by sequencing and phylogenetic analysis in 17 cases. HBV genotype distribution in Japanese and Bolivians was HBV/F (4 and 8); HBV/C (5 and 3); and HBV/B (1 and 1), respectively. Phylogenetic analyses of nine complete and eight partial (HBsAg/pre-core/core region) genomes, revealed that HBV/F strains cluster with previously reported regional strains, whereas HBV/B and HBV/C strains belonged to Asian subgenotype B2 (Ba) and C2 (Ce), respectively. Japanese immigrants might have introduced HBV/B and HBV/C to natives in Bolivia, conversely, exposed to the indigenous HBV/F. This report provides evidence of an inter-communities transmission of HBV revealed by its genotypes. Further study is required to investigate peculiarities of the genotypes in different ethnic groups in Bolivia.  相似文献   

14.
Whether resistant hepatitis B virus (HBV) strains are transmissible and can lead to chronic infection remains to be studied. The aim of this study was to investigate the clinical characteristics of patients with acute hepatitis B caused by lamivudine (LAM)‐resistant strains. Sera were collected from 234 Chinese patients with acute hepatitis B. LAM‐resistance mutations were identified by direct polymerase chain reaction (PCR) sequencing. LAM‐resistant HBV variants were detected in 11 of the 234 (4.7%) patients. Among these patients, six harbored the rtM204I mutation, two harbored the rtL180M + rtM204I mutations, one harbored the rtM204I + rtM204V mutations, one harbored the rtL80I + rtM204I mutations, and one harbored the rtV173L + rtL180M + rtM204V mutations. Three patients were infected with genotype B HBV and eight patients were infected with genotype C HBV. Two patients infected with viruses with LAM‐resistance mutations developed severe acute hepatitis. One patient developed chronic hepatitis B. This patient was infected with genotype C HBV that had LAM‐resistance mutations (rtL180M + rtM204I). The patient was diagnosed with an occult hepatitis B virus infection based on the presence of HBV DNA in the liver and the absence of detectable hepatitis B surface antigen (HBsAg) in the serum. LAM‐resistant HBV strains in China are transmissible, can cause acute hepatitis B, and can even progress to chronic infection in China. J. Med. Virol. 84:1558–1561, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   

15.
The long-term persistence of immunity following universal infant immunization against hepatitis B virus (HBV) and the need for a subsequent booster dose in adolescence remain under debate. With data derived from Long'an County, Guangxi, China, we reported previously that the prevalence of hepatitis B surface antigen (HBsAg) among adults born from 1987 to 1993 increases with age, although these individuals had received a first dose of the vaccine within 24 hours of birth. Here, we sought the source of transmission by comparison of genotypes among their family members using phylogenetic analysis of complete HBV S gene sequences. For comparison, we screened 2199 vaccinated individuals aged 5 to 17 in Cang Wu County and 1592 vaccinated individuals aged 3 to 7 in Ling Shan County in Guangxi for HBsAg carriers and investigate their family members. In total, 50 asymptomatic HBsAg carriers who were vaccinated at birth and 152 family members were analyzed. The results showed that 25% (95% CI: 6.0-44.0) of the HBsAg-positive children had not acquired their HBV infection from their mothers. This phenomenon showed a trend that increases with age. Antibody escape mutations were detected in 22.9% (95% CI: 11.0-34.8) of the isolates. In conclusion, a booster dose may be necessary for adolescence who were vaccinated at birth in highly endemic countries.  相似文献   

16.
During 35 years from 1971 to 2005, 153 patients with acute and 4,277 with chronic HBV infection visited the Toranomon Hospital in Tokyo, Japan. They were grouped into seven 5-year periods, and HBV genotypes/subgenotypes were determined. Patients with acute HBV infection were younger (P = 0.046), predominantly male (P = 0.004), possessed higher alanine aminotransferase levels (P < 0.001), positive more frequently for HBeAg (P < 0.001), and had lower HBV DNA loads (P = 0.014) than those with chronic infection. Sexual transmission was more frequent in patients with acute than chronic HBV infection (67% vs. 3%, P < 0.001). The number of patients with acute infection increased throughout 1971-2005. Patients with chronic infection increased since 1971, peaked in 1986-1990 and then decreased. The number of patients increased since 1990-2000 again, however, reflecting recent boost of acute HBV infection. The distribution of HBV genotypes was considerably different between patients with acute and chronic infections (A, B, and C: 28.6%, 10.3%, and 59.5% vs. 3.0%, 12.3%, and 84.5%, respectively, P < 0.001). Since 1991, genotype A foreign to Japan started to increase sharply in patients with acute infection, and gradually in those with chronic infection. There was a trend for the foreign subgenotype B2/Ba to increase recently (P < 0.05). Despite immunoprophylaxis of high-risk babies born to carrier mothers with hepatitis B e antigen, implemented nationally since 1986, acute and chronic infections with HBV have been increasing in Japan. Based on genotypes/subgenotypes changing with time, the resurgence of hepatitis B could be attributed to infections, with foreign HBV genotypes/subgenotypes, spreading swiftly by sexual contact.  相似文献   

17.
Human immunodeficiency virus type 2 (HIV-2) infection is endemic in West Africa, where it is responsible for many cases of AIDS. HIV-2-infected subjects have been described in other countries, mainly African immigrants, although infection in native individuals has been reported as well. The first cases of HIV-2 infection in Spain were identified in 1988. Through December 1995, 56 HIV-2-infected individuals have been diagnosed, primarily in large urban areas (23 cases in Madrid and 18 in Barcelona). All are African immigrants, except for 12 natives (21.4%), six of whom acquired the infection in endemic areas; the remaining six (2 women with numerous sexual partners and 4 homo/bisexual men) acquired the infection in Spain. Heterosexual transmission was probable in all but seven cases: five homo/bisexual males, a subject who likely acquired infection through parenteral exposure, and a child born to an HIV-2-infected mother. Nine patients (all Spanish bom) have developed AIDS (16%), six of whom have died. In conclusion, HIV-2 infection is present in Spain at a low rate, and there is little evidence supporting an emerging ongoing transmission outside the population of African immigrants.  相似文献   

18.
An outbreak of acute hepatitis cases in a small community took place 6 months after the community's arrival to the Brazilian Amazon. An epidemiological investigation was performed and included residents aged more than two years. Study subjects were interviewed and bled to test for hepatitis markers by enzyme immunoassays. Around 80% of the village population was surveyed. The overall prevalence of hepatitis B virus (HBV) markers was 75.1% (281/374). The surface antigen of HBV (HBsAg) and the IgM class antibody against hepatitis B core antigen (IgM anti-HBc) were present in 10.4% and 9.6%, respectively. Evidence of HBV–HDV (Delta virus) coinfection or hepatitis C infection was not found. IgM class antibody against hepatitis A virus was uncommon (3.7%). Follow-up evaluation 6 and 12 months later were carried out to identify new HBV infections. An incidence rate of 7.2 new infections per 100 exposed subjects per month was found. Average individual risk for HBV infection among susceptible inhabitants of the village between June 1995 and June 1996 can be estimated at 57.6%. The predominant HBsAg subtype found (ayw3) suggests that immigrants may have carried HBV from the original area. Time living in the study region was significantly associated with HBV markers in analysis for linear trend and logistic regression analysis. Environmentally related factors may have facilitated HBV transmission. J. Med. Virol. 56:4–9, 1998. © 1998 Wiley-Liss, Inc.  相似文献   

19.
One hundred ten consecutive patients (60 males and 50 females; age, mean +/- standard deviation [SD], 22.6 +/- 6.4 years; range 16-48 years) who were clinically diagnosed with sporadic acute hepatitis between December 2004 and January 2005 in Ulaanbaatar, Mongolia, were studied. IgM antibodies to hepatitis A virus were detected in 18 patients (16.4%), IgM antibodies to hepatitis B core (anti-HBc IgM) in 38 patients (34.5%) including two patients with concurrent hepatitis delta virus (HDV) infection, and hepatitis C virus RNA in nine patients (8.2%). There were 30 hepatitis B virus (HBV) carriers who had detectable hepatitis B surface antigen and antibodies to HDV but were negative for anti-HBc IgM, suggesting that they acquired type D acute hepatitis due to superinfection of HDV on a background of chronic HBV infection. None had IgM antibodies to hepatitis E virus (HEV). Consequently, 16.4, 32.7, 6.4, 1.8, and 27.3% of the patients were diagnosed as having acute hepatitis of type A, B, C, type B + D (HBV/HDV coinfection), and type D (superinfection of HDV), respectively. The cause of hepatitis was not known in the remaining 17 patients (15.5%). All 18 HAV isolates were genotyped as IA, all 9 HCV isolates were genotyped as 1b, and all 32 HDV isolates were classified into genotype I. The distribution of HBV genotypes among the 67 HBV isolates was A (1.5%, n = 1) and D (98.5%, n = 66). The present study indicates that de novo infections of HAV, HBV, HCV, and HDV are prevalent among young adults in Mongolia.  相似文献   

20.
The antibody against the core component of the Dane particle (anti-HBc) is generally detected in the sera of individuals with acute type B hepatitis and in chronic HBsAg carriers. While the serological demonstration of HBsAg with or without anti-HBc indicates continued replication of viral antigens, the co-occurrence of anti-HBs and anti-HBc is considered a marker of recent HBV replication. The demonstration of anti-HBc in the absence of HBsAg and anti-HBs is in agreement with at least four different states of HBV infection. As this pattern indicates persistent HBV infection in some cases and recovery from an acute type B hepatitis in others, current efforts focus on further characterization of this pattern, using additional test methods such as anti-HBe and anti-HBc of the IgM class.  相似文献   

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