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In September 2010, an outbreak of acute hepatitis B virus (HBV) infections in a nursing home was notified to public health authorities in Northern Germany. To identify the route of transmission and prevent further cases a retrospective cohort study was conducted. Blood samples of residents were tested for serologic markers of HBV infection and HBV subgenotypes and sequences were analyzed. Outbreak-related cases were defined as residents of the nursing home with detection of hepatitis B surface antigen (HBsAg) and the HBV DNA sequence of the outbreak strain in 2010. Information on possible risk factors as patient care, invasive diagnostic, and therapeutical procedures was collected using a standardized questionnaire. Risk ratios (RR) and 95% confidence intervals (CI) were estimated with exact Poisson regression and binomial regression. Sixty-four residents were included in the study, 5 of them were outbreak-related cases, 12 had a past HBV infection. The outbreak strain belonged to HBV genotype D2 (HBsAg subtype ayw3, Ala118) which is not prevalent in Germany but in Eastern Europe. All cases (median age 81) were female, had diabetes, blood glucose monitoring, and chiropody. In multivariable analysis only blood glucose monitoring was associated with HBV infection (RR = 22, 95%CI 3.0-∞). Blood glucose monitoring was reported to be done by nursing home staff with patient-based reusable lancet devices. In nursing home settings the use of single use lancets for blood glucose monitoring is recommended strongly to prevent transmission. National guidelines on the handling of point-of-care devices and reusable equipment in long-term care facilities should be developed.

Heterogeneities in the density of hepatitis C virus (HCV)-RNA-carrying material from human sera (1.03-1.20 g/ml) are partially due to the binding of lipoproteins [low density (LDL), very low density (VLDL), high density (HDL) lipoproteins] and immunoglobulins. In this study we demonstrate the binding of recombinant HCV envelope protein (El/E2) to human LDL, VLDL and HDL on a molecular basis. The binding of lipoproteins was restricted to the middle part of the El gene product (amino acids 222-336) and the C-terminal part of the E2 protein (amino acids 523-809). Lipoproteins did not bind to recombinant HCV core protein.

The hepatitis C virus (HCV) interferon-alpha (IFN-alpha) sensitivity-determining region (ISDR) has been shown to suppress double-stranded RNA-dependent protein kinase (PKR) activity in vitro in a yeast PKR expression system. Since variability of ISDR was shown to correlate with nonresponsiveness to IFN-alpha therapy in chronically HCV-infected patients, it has been suggested that prototype ISDR might be a viral inhibitor of cellular PKR. The present study evaluates the biological significance of ISDR variability in situ, relating it to PKR-mediated cellular antiviral responses within the liver. ISDR variability was determined in patients chronically infected with HCV genotypes 1a, 1b, and 3a by direct sequencing using liver-derived RNA preparations as starting material. As surrogate parameters for PKR-mediated cellular responses, hepatic endogenous IFN-alpha gene expression as well as MxA expression were analysed by a competitive, quantitative reverse transcription-polymerase chain reaction technique. Irrespectively of intra- or intergenotypic ISDR amino acid substitutions, ISDR variability was found not to correlate with endogenous hepatic IFN-alpha or with hepatic MxA gene expression. The data suggest that at least two prominent PKR-mediated cellular responses might be largely unaffected by HCV ISDR variability.

Chronic hepatitis C virus (HCV) infection in humans is treated at present with interferon (IFN)-α. Because the proportion of patients responding to therapy with sustained or even just with transient elimination of viral RNA is low, several potential prognostic parameters have been evaluated to predict the outcome of the therapy. The present study aimed to prove the validity of a predictive parameter described previously for initial virological response, namely the ratio of serum γ-glutamyltransferase/alanine transaminase (γ-GT/ALT) activity in connection with virus genotypes 1a, 1b, and 3a, prospectively and to compare the predictive value of these combined parameters with amino acid variability within the interferon sensitivity determining region (ISDR). The prospective analysis confirmed previous data on the predictive value of the serum γ-GT/ALT ratio. Concerning ISDR variability, the majority of ISDR sequences obtained from the mostly nonresponding type 1b-infected individuals (23/28) resembled nonmutant types (27/28). Isolates from type 3a-infected patients responding to therapy in the majority of cases (13/20) exclusively resembled nonmutant types when compared with databank type 3a sequences, but were mutant when compared with the prototype sequence HCV-J. However, the initial virological responsiveness among both type 1b- and type 3a-infected patients did not correlate to ISDR variability. In contrast, virological responsiveness was closely related to serum γ-GT/ALT ratio. The data are not necessarily contrary to the concept that the number of amino acid exchanges within the ISDR compared with the prototype HCV-J sequence is related to some extent to IFN-α sensitivity. The ratio of serum γ-GT/ALT in combination with HCV genotype, however, was found to be a more reliable and stringent predictive parameter. J. Med. Virol. 58:227–234, 1999. © 1999 Wiley-Liss, Inc.

Hepatitis C virus (HCV) binds to different human cell lines in vitro. However, the efficiency of adsorption is very low due mainly to a relatively small fraction of the virus being able to bind to these cells. Free low density lipoprotein (LDL > 200 μg/ml) is able to block the attachment of HCV to human fibroblasts in vitro completely. COS-7 cells being primarily not able to bind HCV were transfected with a vector containing the entire coding sequence of the human LDL-receptor (LDLR). HCV was now bound to these cells. We propose that HCV and LDL are competitive for the cellular LDLR and that LDL in sera of patients may regulate the binding of HCV to this target. J. Med. Virol. 57:223–229, 1999. © 1999 Wiley-Liss, Inc.

Treating acute hepatitis C with interferon alpha prevents chronicity in nearly all cases when therapy is initiated within 3 months after infection. However, 15-50% of untreated patients may clear the hepatitis C virus (HCV) spontaneously. Therefore, factors are needed to identify patients prior to therapy who have a higher or lower risk for developing a chronic course to avoid unnecessary treatment. The role of the HCV genotype for spontaneous recovery from acute hepatitis C has been discussed controversially. In the year 2002, all 1,176 new incoming prisoners in a Northern German prison for young men (age 16-24) were screened for anti-HCV antibodies and 92 tested positive. Ninety eight percent of these reported i.v.-drug abuse for a median of 32 months prior to imprisonment. HCV-RNA negative individuals (21%) were serotyped and HCV-RNA positive patients were genotyped. The prevalence of HCV genotype 3 was significantly higher among individuals who had cleared HCV spontaneously as compared to chronically infected patients (86% vs. 38%; P = 0.002). Ninety three percent of individuals exposed to HCV genotype 1 but only 63% of individuals exposed to genotype 3 experienced a chronic course of the infection (P = 0.006). Thus, acute infection in young Caucasian men with HCV genotype 3 leads more often to spontaneous clearance than infection with HCV genotype-1. Considering also the high chance of successful treatment of chronic HCV genotype 3 infection with pegylated-interferon in combination with ribavirin, we suggest not to treat acute hepatitis C genotype 3 infection early but rather to wait at least 3 months after the onset of symptoms when chronicity becomes likely.

Shiga toxin (Stx)-producing Escherichia coli (STEC) is a major cause of sporadic cases of disease as well as serious outbreaks worldwide. The spectrum of illnesses includes mild nonbloody diarrhea, hemorrhagic colitis, and hemolytic-uremic syndrome. STEC produces one or more Stxs, which are subdivided into two major classes, Stx1 and Stx2. The ingestion of contaminated food or water, person-to-person spread, and contact with animals are the major transmission modes. The infective dose of STEC may be less than 100 organisms. Effective prevention of infection is dependent on rapid detection of the causative bacterial pathogen. In the present study, we examined 295 stool specimens for the presence of Stx-producing E . coli by three different methods: an Stx enzyme-linked immunosorbent assay, a conventional PCR assay, and a LightCycler PCR (LC-PCR) assay protocol recently developed by our laboratory at the Institute of Medical Microbiology at Hannover Medical School. Our intent was to compare these three methods and to examine the utility of the STEC LC-PCR protocol in a clinical laboratory. The addition of a control DNA to each sample to clearly discriminate inhibited specimens from negative ones enhanced the accuracy of the LC-PCR protocol. From our results, it can be concluded that LC-PCR is a very useful tool for the rapid and safe detection of STEC in clinical samples.

Association of the hepatitis C virus (HCV) with apolipoprotein B containing lipoproteins has been suggested, and this led to the concept that the low-density lipoprotein (LDL) receptor may also serve as a candidate receptor for HCV uptake into the liver. We have investigated whether heparin-induced extracorporeal LDL precipitation (HELP) LDL apheresis treatment reduces HCV plasma load in 6 patients, all infected for more than 4 years with HCV and resistant against established anti-HCV therapy. HELP apheresis treatment caused an HCV-RNA decrease of 77.3% in mean. This decline was not correlated with LDL-cholesterol reduction. HCV-RNA was retained on the HELP filter as shown for 1 patient. The effect of RNA lowering was only transient due to the high turnover of HCV. However, HELP apheresis may open a window of opportunity for an immune-modulating and antiviral therapy in the interval between two apheresis procedures in patients with high virus load.

Infection with hepatitis C virus (HCV) is still a serious problem in hemodialysis patients, despite screening of blood products for anti-HCV antibodies. The prevalence of HCV in HD patients is between 15% and 30% in Germany. We report the molecular epidemiology of an HCV outbreak in a hemodialysis unit in 1997 is determined. HCV hypervariable region 1 (HVR1) was amplified from serum samples of 19 patients by polymerase chain reaction (PCR) and sequenced directly. In addition, HCV isolates from 3 of these 19 patients were cloned and sequenced. 14 newly infected patients and two patients, who had been infected for several years had very closely related HCV isolates. Unrelated HCV isolates as well as sequences obtained from an HCV outbreak in a plasmapheresis center were found in different, distantly related branches. These findings provide strong evidence for nosocomial transmission of the virus, despite following strict general hygiene precautions. The production of anti-HCV antibody was delayed significantly or seroconversion did not occur at all during the period of observation in 8 out of 14 newly infected HCV RNA positive patients. Close-meshed reverse transcription-polymerase chain reaction (RT-PCR) analyses on apparently non infected patients within hemodialysis units and upon admission of new patients is strongly recommended for the early detection and prevention of outbreaks of HCV.

Hepatitis B virus DNA was extracted from serial serum samples of a hepatitis B surface antigen-negative patient with antibodies to the core protein as the only marker of an infection with hepatitis B virus. This patient showed no symptoms of hepatic injury. Sequencing of the amplified viral DNA demonstrated multiple amino acid changes clustering in surface-exposed regions of the surface protein. Synthesis and association of the middle (M) and small (S) surface proteins could be shown in vitro. The variant surface antigens were recognized neither by monoclonal antibodies to the surface antigen nor by the vaccinee’s sera. Consequences for hepatitis B surface antigen testing and vaccine development are discussed.

Background The association of HCV with apolipoprotein B containing lipoproteins has been observed and this led to the assumption that the LDL receptor may also serve as a candidate receptor for HCV. H.E.L.P.-LDL apheresis is suggested to be an effective and rapid tool to safely eliminate apolipoprotein B containing lipoproteins. Materials and methods In this pilot study, we have investigated whether H.E.L.P. treatment would reduce HCV load in five patients, all infected for more than 4 years with HCV and resistant against established anti-HCV therapy (interferon, ribaverin). HCV-RNA was determined by RT-PCR in plasma immediately before the start of apheresis (SA) and after treatment of 2500 mL plasma (AA). Results H.E.L.P. apheresis led to a mean decrease of 77.3% (16th percentile 36.5%, 84th percentile 89.6%) of HCV-RNA when AA values were compared to SA values. This decline was reproducible during nine treatment procedures, but was not correlated to the decrease in LDL cholesterol. Conclusions This investigation shows for the first time that HCV load can be reduced by H.E.L.P. apheresis, which is an established and approved therapy for hypercholesterolemia. Even though the efficiency of viral load reduction varied between single procedures and did not correlate to LDL removal, this extracorporeal therapy opens the possibility to treat patients with established immune modulatory and antiviral therapy in the interval between two apheresis procedures.