Publications (19)65.01 Total impact
-
Article: Seroprevalence and incidence of hepatitis E virus infection in German blood donors.
[show abstract] [hide abstract]
ABSTRACT: BACKGROUND: Hepatitis E virus (HEV) is transmissible by transfusion. More data are needed about seroprevalence, incidence, and viremia in blood donors for the assessment of risk of transfusion-transmitted (TT)-HEV infections. STUDY DESIGN AND METHODS: Samples from 1019 whole blood donors were tested for anti-HEV immunoglobulin (Ig)G by enzyme-linked immunosorbent assay and Western blot. The incidence of HEV and presence of HEV RNA in donors who seroconverted were determined by testing archive samples and recipients of viremic donations were traced. Anti-HEV IgM and alanine transaminase (ALT) testing were also performed to assess the value of such measures in the prevention of TT-HEV infections. RESULTS: A total of 69 of 1019 donors tested positive for anti-HEV IgG (6.8% seroprevalence), and seroconversion for anti-HEV IgG occurred in seven of 69 donors within 2 years (incidence, 0.35%/year). Three of seven (42.8%) seroconverting donors provided an archive sample in which HEV RNA was detectable. One recipient of these donations was traceable; anti-HEV IgG, IgM, and HEV RNA testing were negative 41 days after transfusion. Neither ALT levels nor anti-HEV IgM detection correlated with the presence of HEV RNA. CONCLUSIONS: The seroprevalence of HEV was 6.8%, and the annual incidence 0.35%. HEV RNA was detectable in several seroconverting donors, without evidence for HEV transmission in the only traceable recipient. Since neither ALT nor anti-HEV IgM testing correlate with the presence of HEV RNA, HEV nucleic acid testing currently provides the only method for the prevention of TT-HEV infection. However, before implementation, more data about clinical relevance of TT-HEV infections and infectious dose of HEV are required.Transfusion 02/2013; · 3.22 Impact Factor -
Article: Inactivation and neutralization of parvovirus B19 Genotype 3.
[show abstract] [hide abstract]
ABSTRACT: Parvovirus B19 (B19V) is a common contaminant of human plasma donations. Three B19V genotypes have been defined based on their DNA sequence. Reliable detection of Genotype 3 DNA has proved problematic because of unexpected sequence variability. B19V Genotype 3 is found primarily in West Africa, but was recently detected in plasma from a North American donor. The safety of plasma-derived medicinal products, with respect to B19V, relies on exclusion of high-titer donations, combined with virus clearance at specific manufacturing steps. Studies on inactivation of B19V are difficult to perform and inactivation of Genotype 3 has not yet been investigated. Inactivation of B19V Genotypes 3 and 1 by pasteurization of human serum albumin and incubation at low pH was studied using a cell culture assay for infectious virus particles. Infected cells were detected by reverse transcription-polymerase chain reaction analysis of virus capsid mRNA. Neutralization of B19V Genotype 3 was investigated using human immunoglobulin preparations. Genotypes 1 and 3 displayed comparable inactivation kinetics during pasteurization of albumin at 56°C, as well as by incubation at various low-pH conditions (pH 4.2 at 37°C and pH 4.5 at 23°C, respectively) used in immunoglobulin manufacturing. Both Genotypes were readily neutralized by pooled immunoglobulin preparations of North American or European origin. Pasteurization and low-pH treatment were equally effective in inactivating B19V Genotypes 1 and 3. Neutralization experiments indicated that pooled immunoglobulin of North American or European origin is likely to be equally effective in treatment of disease induced by both genotypes.Transfusion 02/2012; 52(7):1490-7. · 3.22 Impact Factor -
Article: Standardization of hepatitis E virus (HEV) nucleic acid amplification technique-based assays: an initial study to evaluate a panel of HEV strains and investigate laboratory performance.
[show abstract] [hide abstract]
ABSTRACT: The performance of hepatitis E virus (HEV) RNA nucleic acid amplification (NAT)-based assays has been investigated using a panel of HEV-containing plasma samples. The panel comprised 22 HEV-positive plasma samples representing 10-fold serial dilutions of HEV genotypes 3a, 3b, 3f, and 4c obtained from blood donors. Two negative-control plasma samples were included. All samples were blinded. The plasma samples were prepared as liquid/frozen materials and distributed to participants on dry ice. Laboratories were requested to test the panel using their routine HEV assays and to score samples as either positive or negative and could optionally return data in copies/ml for HEV RNA. Twenty laboratories from 10 different countries participated in the study. Data were returned by all participating laboratories; 10 laboratories returned quantitative data. All assays except one were developed in-house using conventional or real-time reverse transcriptase PCR (RT-PCR) methodologies. There was a 100- to 1,000-fold difference in sensitivity between the majority of assays, independent of the virus strain. Although the quantitative data were limited, for the samples in the range of ∼6 to 4 log(10) copies/ml, the standard deviations of the geometric means of the samples ranged between 0.38 and 1.09. Except for one equivocal result, HEV RNA was not detected in the negative samples. The variability of assay sensitivity highlights the need for the standardization of HEV RNA NAT assays.Journal of clinical microbiology 02/2011; 49(4):1234-9. · 4.16 Impact Factor -
Article: Analysis of porcine circovirus type 1 detected in Rotarix vaccine.
[show abstract] [hide abstract]
ABSTRACT: A metagenomic analysis of live human vaccines has recently demonstrated the presence of porcine circovirus type 1 (PCV1) DNA in the paediatric vaccine Rotarix used in the prevention of acute gastroenteritis. Using real-time PCR for PCV1, titres of PCV1 DNA in several batches of Rotarix were found to be in the order of 6-7 log(10) copies per dose. Pre-treatment of the reconstituted vaccine with the nuclease Benzonase, followed by extraction of nucleic acid and quantification of PCV1 DNA by real-time PCR, revealed that there was no loss of PCV1 DNA titre compared to untreated controls, suggesting that the porcine viral DNA was present in the vaccine in an encapsidated form. PCV1 permissive PS cells, human HEK293 and Vero cells, used for vaccine production, were infected with Rotarix or PCV1, respectively, and subjected to immune fluorescence and RT-PCR. Viral genomes were present in Rotarix-incubated as well as PCV1-infected cells, while viral transcription was seen only in PCV1-infected cells. Similarly, PCV1-specific protein expression was observed in PCV1-infected cells, but not in cells treated with Rotarix. Passaging of the supernatant indicated productive infection in PCV1-infected PS cells, but not in HEK293 and Vero cells or in any cell line incubated with Rotarix. PCV1 DNA present in Rotarix was protected from Benzonase digestion; however, PCV1 was not recognized in immune electron microscopy and unable to infect PS, HEK293 or Vero cells, suggesting that the high amount of PCV1 DNA present in Rotarix does not reflect a corresponding proportion of biologically active virus particles.Vaccine 01/2011; 29(4):690-7. · 3.77 Impact Factor -
Article: Identification and characterization of acute infection with parvovirus B19 genotype 2 in immunocompromised patients in Poland.
[show abstract] [hide abstract]
ABSTRACT: Parvovirus B19 (B19V) is divided into three genotypes. Genotypes 2 and 3 may cause diagnostic difficulties and their epidemiology is not well understood. In the present study the prevalence of B19V genotypes in patients with symptomatic infection in Poland was evaluated and the course of infection in patients infected with non-genotype 1 strains is described. Real-time PCR, able to detect all three genotypes of B19V was used to screen patient plasma samples. Sixty-nine, mainly acute-phase B19V DNA positive cases were identified in patients from hematological and obstetric/gynecological wards between 2004 and 2008. Thirty patients were studied in greater detail and genotyping was performed by analysis of the NS1/VP1u region. The majority of samples were genotype 1. However two (6.6%) strains were identified as genotype 2, associated with high viremia and identified in a kidney transplant recipient with anemia and a leukemia patient, following chemotherapy, with pancytopenia. A change of immunosuppression treatment in the former and treatment with intravenous immunoglobulin in latter, resulted in normalization of clinical parameters, and whilst viral loads fell, B19V DNA was still detectable. The kidney transplant recipient subsequently became pregnant with no clinical complications, although persistently infected with B19V genotype 2. This is the first description of symptomatic cases of genotype 2 B19V infection in Eastern Europe suggesting that acute infection, particularly among immunocompromised patients with these virus strains may be more prevalent than thought.Journal of Medical Virology 01/2011; 83(1):142-9. · 2.82 Impact Factor -
Article: Hepatitis E virus and blood donors in Germany.
Vox Sanguinis 02/2010; 98(3 Pt 2):479. · 2.86 Impact Factor -
Article: Absence of detection of novel human parvoviruses in German plasma donations.
Transfusion 01/2010; 50(1):266-7. · 3.22 Impact Factor -
Article: Establishment of the 1st World Health Organization international standards for human papillomavirus type 16 DNA and type 18 DNA.
[show abstract] [hide abstract]
ABSTRACT: A World Health Organization collaborative study was conducted to evaluate candidate international standards for human papillomavirus (HPV) Type 16 DNA (NIBSC code 06/202) and HPV Type 18 DNA (NIBSC code 06/206) for use in the amplification and detection steps of nucleic acid-based assays. The freeze-dried candidate international standards were prepared from bulk preparations of cloned plasmid containing full-length HPV-16 or HPV-18 genomic DNA. Nineteen laboratories from 13 countries participated in the study using a variety of commercial and in-house quantitative and qualitative assays. The data presented here indicate that, upon freeze-drying, there is no significant loss in potency for the candidate HPV-18 DNA and a slight loss in potency for the candidate HPV-16 DNA; although this is likely not scientifically relevant when assay precision is considered. In general, the individual laboratory mean estimates for each study sample were grouped +/- approximately 2 log(10) around the theoretical HPV DNA concentration of the reconstituted ampoule (1 x 10(7) HPV genome equivalents/mL). The agreement between laboratories is improved when potencies are made relative to the candidate international standards, demonstrating their utility in harmonizing amplification and detection steps of HPV-16 and -18 DNA assays. Degradation studies indicate that the candidate international standards are extremely stable and suitable for long-term use. Based on these findings, the candidate standards were established as the 1st WHO international standards for HPV-16 DNA and HPV-18 DNA, each with a potency of 5 x 10(6) international units (IU) per ampoule or 1 x 10(7) IU mL(-1) when reconstituted as directed.International Journal of Cancer 11/2009; 126(12):2969-83. · 5.44 Impact Factor -
Article: Development of working reference materials for clinical virology.
[show abstract] [hide abstract]
ABSTRACT: Nucleic acid amplification technique (NAT)-based assays are replacing traditional diagnostic methods in clinical laboratories. However, many of these assays are developed in-house and the lack of standardised reference materials has hindered assay implementation and control. Consequently, in the UK, the Clinical Virology Network (CVN), the National Institute for Biological Standards and Control (NIBSC), and the Health Protection Agency (HPA), are working in collaboration to develop working standards or 'run controls' for diagnostic NAT-based assays, particularly real-time PCR. These run controls are intended for use in microbiology laboratories and are designed to be extracted and amplified in the same way as clinical samples and included in each assay run. The aim is to enable clinical laboratories to continuously monitor the performance of their diagnostic NAT assays on a run-by-run basis allowing inter-laboratory comparisons, and ultimately improving the consistency of results. At present, eight candidate run controls representing clinically relevant viral targets have been prepared for evaluation by CVN laboratories. Data have been returned on the performance of each run control in routine diagnostic assays. Preliminary results presented here indicate a high level of variability in intra- and inter-assay detection of these targets, highlighting the need for standardisation of assays within molecular diagnostics.Journal of Clinical Virology 10/2008; 43(4):367-71. · 3.97 Impact Factor -
Article: Persistence of novel human parvovirus PARV4 in liver tissue of adults.
[show abstract] [hide abstract]
ABSTRACT: Human parvovirus 4 (PARV4) is a recently identified virus whose biology, epidemiology and pathogenic potential have yet to be determined. Recently, it was reported that PARV4 DNA persists in tissues of some HIV-infected individuals, whilst PARV4 DNA was not detected in tissues of subjects not infected with HIV. In the present study, liver tissue from 87 individuals, none of who were infected with HIV, with the exception of a single subject, was analyzed for the presence of PARV4 DNA. Overall, PARV4 DNA was detected in 13 specimens (15%). In other tissues examined, PARV4 genotype 2 (also termed PARV5) DNA was detected in one of four paired bone marrow specimens. Tissue viral loads did not exceed 100 copies per microg of genomic DNA. In addition, serum samples from 40 of these individuals all tested negative for PARV4 DNA. In the subjects analyzed in this study, PARV4 genotype 2 appeared to be genetically more heterogeneous than PARV4 genotype 1. The results show that PARV4 DNA can be detected in liver, and that infection with PARV4 is not restricted to HIV-infected individuals. Previous studies showing the presence of PARV4 in plasma, suggest that during infection with PARV4, a viraemic stage occurs, allowing systemic spread to a variety of tissues.Journal of Medical Virology 03/2008; 80(2):345-51. · 2.82 Impact Factor -
Article: Establishment of the 1st World Health Organization International Standard for Plasmodium falciparum DNA for nucleic acid amplification technique (NAT)-based assays.
[show abstract] [hide abstract]
ABSTRACT: In order to harmonize results for the detection and quantification of Plasmodium falciparum DNA by nucleic acid amplification technique (NAT)-based assays, a World Health Organization (WHO) collaborative study was performed, evaluating a series of candidate standard preparations. Fourteen laboratories from 10 different countries participated in the collaborative study. Four candidate preparations based upon blood samples parasitaemic for P. falciparum were evaluated in the study. Sample AA was lyophilized, whilst samples BB, CC and DD were liquid/frozen preparations. The candidate standards were tested by each laboratory at a range of dilutions in four independent assays, using both qualitative and quantitative NAT-based assays. The results were collated and analysed statistically. Twenty sets of data were returned from the participating laboratories and used to determine the mean P. falciparum DNA content for each sample. The mean log10 "equivalents"/ml were 8.51 for sample AA, 8.45 for sample BB, 8.35 for sample CC, and 5.51 for sample DD. The freeze-dried preparation AA, was examined by accelerated thermal degradation studies and found to be highly stable. On the basis of the collaborative study, the freeze-dried material, AA (NIBSC code No. 04/176) was established as the 1st WHO International Standard for P. falciparum DNA NAT-based assays and has been assigned a potency of 10(9) International Units (IU) per ml. Each vial contains 5 x 10(8) IU, equivalent to 0.5 ml of material after reconstitution.Malaria Journal 01/2008; 7:139. · 3.19 Impact Factor -
Article: Analysis of two human parvovirus PARV4 genotypes identified in human plasma for fractionation.
[show abstract] [hide abstract]
ABSTRACT: The presence of the novel parvovirus PARV4 and a related variant, PARV5, was recently demonstrated in pooled plasma used in the manufacture of blood and plasma-derived medicinal products. DNA sequence analysis of nearly full-length genomes of four PARV4 and two PARV5 strains from manufacturing plasma pools is now presented. Like PARV4, PARV5 encodes two non-overlapping open reading frames (ORF1 and ORF2), homologous to the non-structural and capsid proteins of other parvoviruses, respectively. A highly conserved region in ORF2 contains phospholipase A2 motifs involved in parvovirus infectivity. Hybridization of strand-specific probes to DNA extracted from high-titre, PARV4-positive plasma revealed that the positive and negative strands are packaged into PARV4 virions in similar quantities. This extended analysis of nearly full-length PARV4 and PARV5 sequences suggests that they are closely related genotypes and the use of a single virus name, PARV4, comprising genotypes 1 and 2 (previously termed PARV5) is proposed.Journal of General Virology 09/2007; 88(Pt 8):2162-7. · 3.36 Impact Factor -
Article: Frequent detection of the parvoviruses, PARV4 and PARV5, in plasma from blood donors and symptomatic individuals.
[show abstract] [hide abstract]
ABSTRACT: Plasma pools used in the manufacture of blood- and plasma-derived medicinal products are frequently contaminated with parvovirus B19. The presence of the novel human parvovirus PARV4 and a related variant PARV5 in manufacturing plasma pools was recently demonstrated. Another recently identified parvovirus, human bocavirus (HBoV), has been identified in respiratory samples from children with lower respiratory tract disease. Recent and archived manufacturing plasma pools, as well as plasma from healthy blood donors (individual donations; pools of 16 donations) and febrile patients, were examined for the presence of PARV4 and PARV5 with conventional and TaqMan polymerase chain reaction assays. In addition, highly sensitive assays were used to examine the presence of HBoV DNA in manufacturing pools. Of 351 recent manufacturing plasma pool samples, 14 (4%) tested positive for the presence of PARV4 and PARV5. This frequency was elevated in the archived pools. Viral loads ranged from less than 100 up to 4 million copies per mL plasma, with some pools containing a mixture of both viruses. In individual plasma samples from healthy blood donors and febrile patients, the frequencies of detection were 2 and 6 percent, respectively. No HBoV sequences were identified in manufacturing plasma pools (n = 167). PARV4 and PARV5 are readily detected in manufacturing plasma pools, test pools (constructed from 16 donations), and individual donations derived from healthy blood donors. The prevalence of these viruses was increased in plasma samples from febrile patients. Despite the use of highly sensitive assays for HBoV, it was not possible to identify manufacturing plasma pools containing HBoV sequences.Transfusion 07/2007; 47(6):1054-61. · 3.22 Impact Factor -
Article: Parvoviruses PARV4/5 in hepatitis C virus-infected patient.
Emerging infectious diseases 02/2007; 13(1):175-6. · 6.17 Impact Factor -
Article: Effects of probe binding mutations in an assay designed to detect parvovirus B19: implications for the quantitation of different virus genotypes.
[show abstract] [hide abstract]
ABSTRACT: Quantitative real-time PCR is being widely used in the identification of plasma donations that contain high levels of parvovirus B19, to ensure their exclusion from start pools used in the manufacture of plasma derived medicinal products. In this study, the primers and probe of one such published assay, are examined for their ability to quantify different genotypes of parvovirus B19. Under standard assay conditions, there is a failure to detect and quantify one genotype 3 subtype. Alterations in assay conditions can restore quantitation of this subtype.Journal of Virological Methods 02/2007; 139(1):97-9. · 2.01 Impact Factor -
Article: Novel parvovirus and related variant in human plasma.
[show abstract] [hide abstract]
ABSTRACT: We report a novel parvovirus (PARV4) and related variants in pooled human plasma used in the manufacture of plasma-derived medical products. Viral DNA was detected by using highly selective polymerase chain reaction assays; 5% of pools tested positive, and amounts of DNA ranged from <500 copies/mL to >106 copies/mL plasma.Emerging infectious diseases 02/2006; 12(1):151-4. · 6.17 Impact Factor -
Article: Evaluation of different assays for the detection of parvovirus B19 DNA in human plasma.
[show abstract] [hide abstract]
ABSTRACT: Human parvovirus B19 is a frequent contaminant of blood and plasma-derived medicinal products and transmission of this virus has been shown to occur through the administration of contaminated products. Inactivation of the virus has proved difficult and as a consequence, manufacturers of blood products have implemented screening measures to reduce the load of parvovirus B19 in manufacturing plasma pools by the use of nucleic acid amplification techniques (NAT). We present data comparing the performance of two commercially available kits for the detection and quantitation of parvovirus B19 DNA using the LightCycler, and determine their applicability for the detection of recently discovered variants of the virus. Parvovirus B19 DNA was readily quantified using both commercial assays. However, one kit failed to detect any of the variant viruses. The second kit detected the variant viruses although there was a marked difference in the sensitivity of detection of the different virus genotypes. To improve the detection of these variant viruses a novel assay has been developed and data are presented to show its use for screening pooled plasma for the presence of parvovirus B19 DNA and the variants identified recently.Journal of Virological Methods 11/2004; 121(1):7-16. · 2.01 Impact Factor -
Article: Simian cytomegalovirus and contamination of oral poliovirus vaccines.
[show abstract] [hide abstract]
ABSTRACT: In the 1950s the use of primary rhesus macaque kidney cultures to propagate poliovirus for vaccine production led to the contamination of vaccines with simian virus 40 (SV40). African green monkey kidney (AGMK) cultures free of SV40 were used as an alternative cell substrate for vaccine manufacture. In this study we evaluate oral poliovirus seeds, vaccine bulks and vaccines themselves for the presence of a common contaminant of AGMK cultures, simian cytomegalovirus (SCMV). Using sensitive polymerase chain reaction (PCR) techniques, nearly half of the samples analysed were found to be contaminated with SCMV sequences. However, vaccine bulks, positive by PCR for SCMV failed to show any evidence of infectious virus in these studies. One poliovirus vaccine and one seed, propagated on rhesus macaque kidney cultures were found to be positive for the rhesus monkey CMV by PCR.Biologicals 04/2003; 31(1):63-73. · 1.70 Impact Factor -
Article: Simian cytomegalovirus and contamination of oral poliovirus vaccines
[show abstract] [hide abstract]
ABSTRACT: In the 1950s the use of primary rhesus macaque kidney cultures to propagate poliovirus for vaccine production led to the contamination of vaccines with simian virus 40 (SV40). African green monkey kidney (AGMK) cultures free of SV40 were used as an alternative cell substrate for vaccine manufacture. In this study we evaluate oral poliovirus seeds, vaccine bulks and vaccines themselves for the presence of a common contaminant of AGMK cultures, simian cytomegalovirus (SCMV). Using sensitive polymerase chain reaction (PCR) techniques, nearly half of the samples analysed were found to be contaminated with SCMV sequences. However, vaccine bulks, positive by PCR for SCMV failed to show any evidence of infectious virus in these studies. One poliovirus vaccine and one seed, propagated on rhesus macaque kidney cultures were found to be positive for the rhesus monkey CMV by PCR.Biologicals 31(1):63-73. · 1.70 Impact Factor
Top co-authors
Top Journals
Institutions
-
2010–2012
-
Paul-Ehrlich-Institut
Langen, Hesse, Germany
-
-
2003–2008
-
National Institute for Biological Standards and Control
- Division of Virology
Potters Bar, ENG, United Kingdom
-
