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1.
United European Gastroenterol J ; 12(3): 339-351, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38279837

ABSTRACT

BACKGROUND: In the third year of the SARS-CoV-2 pandemic, little is known about the vaccine- and infection-induced immune response in liver transplant recipients (LTR) and liver cirrhosis patients (LCP). OBJECTIVE: This cross-sectional study assessed the vaccination coverage, infection rate, and the resulting humoral and cellular SARS-CoV-2-specific immune responses in a cohort of LTR and LCP at the University Medical Center Hamburg-Eppendorf, Germany between March and May 2023. METHODS: Clinical and laboratory data from 244 consecutive patients (160 LTR and 84 LCP) were collected via chart review and a patient survey. Immune responses were determined via standard spike(S)- and nucleocapsid-protein serology and a spike-specific Interferon-gamma release assay (IGRA). RESULTS: On average, LTR and LCP were vaccinated 3.7 and 3.3 times, respectively and 59.4% of patients received ≥4 vaccinations. Altogether, 68.1% (109/160) of LTR and 70.2% (59/84) of LCP experienced a SARS-CoV-2 infection. Most infections occurred during the Omicron wave in 2022 after an average of 3.0 vaccinations. Overall, the hospitalization rate was low (<6%) in both groups. An average of 4.3 antigen contacts by vaccination and/or infection resulted in a seroconversion rate of 98.4%. However, 17.5% (28/160) of LTR and 8.3% (7/84) of LCP demonstrated only low anti-S titers (<1000 AU/ml), and 24.6% (16/65) of LTR and 20.4% (10/59) of LCP had negative or low IGRA responses. Patients with hybrid immunity (vaccination plus infection) elicited significantly higher anti-S titers compared with uninfected patients with the same number of spike antigen contacts. A total of 22.2% of patients refused additional booster vaccinations. CONCLUSION: By spring 2023, high vaccination coverage and infection rate have resulted in a robust, mostly hybrid, humoral and cellular immune response in most LTR and LCP. However, booster vaccinations with vaccines covering new variants seem advisable, especially in patients with low immune responses and risk factors for severe disease.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , Cross-Sectional Studies , Vaccination Coverage , COVID-19/epidemiology , COVID-19/prevention & control , Liver Cirrhosis/epidemiology , Liver Cirrhosis/surgery , Antibodies , Immunity
2.
J Hosp Infect ; 112: 108-113, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33864891

ABSTRACT

BACKGROUND: The presence of coronaviruses on surfaces in the patient environment is a potential source of indirect transmission. Manual cleaning and disinfection measures do not always achieve sufficient removal of surface contamination. This increases the importance of automated solutions in the context of final disinfection of rooms in the hospital setting. Ozone is a highly effective disinfectant which, combined with high humidity, is an effective agent against respiratory viruses. Current devices allow continuous nebulization for high room humidity as well as ozone production without any consumables. AIM: In the following study, the effectiveness of a fully automatic room decontamination system based on ozone was tested against bacteriophage Φ6 (phi 6) and bovine coronavirus L9, as surrogate viruses for the pandemic coronavirus SARS-CoV-2. METHODS: For this purpose, various surfaces (ceramic tile, stainless steel surface and furniture board) were soiled with the surrogate viruses and placed at two different levels in a gas-tight test room. After using the automatic decontamination device according to the manufacturer's instructions, the surrogate viruses were recovered from the surfaces and examined by quantitative cultures. Then, reduction factors were calculated. FINDINGS: The ozone-based room decontamination device achieved virucidal efficacy (reduction factor >4 log10) against both surrogate organisms regardless of the different surfaces and positions confirming a high activity under the used conditions. CONCLUSION: Ozone is highly active against SARS-CoV-2 surrogate organisms. Further investigations are necessary for a safe application and efficacy in practice as well as integration into routine processes.


Subject(s)
Automation/instrumentation , COVID-19/prevention & control , Disinfectants/pharmacology , Disinfection/instrumentation , Disinfection/methods , Ozone/pharmacology , Animals , Bacteriophages/drug effects , COVID-19/transmission , Cattle , Coronavirus, Bovine/drug effects , Cross Infection/prevention & control , Cross Infection/virology , Decontamination/instrumentation , Decontamination/methods , Equipment and Supplies, Hospital/virology , Hospitals , Humans , SARS-CoV-2/drug effects
3.
Rechtsmedizin (Berl) ; 30(3): 184-189, 2020.
Article in English | MEDLINE | ID: mdl-32836897

ABSTRACT

Forensic medicine and pathology involve specific health risks, whereby health workers are dealing with microorganisms, cells or parasites, which are referred to as biological agents. Biological agents are divided into four categories according to § 3 of the Biological Agents Ordinance. The newly identified coronavirus, severe acute respiratory syndrome, coronavirus 2 (SARS-CoV-2) that has spread rapidly around the world is placed into category 3 of the Biological Agents Ordinance, meaning pathogens that can cause serious illnesses in humans and may pose a risk to workers. The Robert Koch Institute, the German government's central scientific institution in the field of biomedicine issued the announcement, that aerosol-producing measures (including autopsies) of SARS-CoV­2 infected bodies should be avoided, despite the fact that autopsies are an important source of understanding the pathomorphological course of new diseases. The first German case of death due to a proven SARS-CoV­2 infection is presented with global multifocal reticular consolidation in the post-mortem computed tomography (CT) scan, a macroscopic and microscopic viral pneumonia and viral RNA of SARS-CoV­2 in pharyngeal mucosa and lung tissue.

4.
Diagn Microbiol Infect Dis ; 96(4): 114977, 2020 Apr.
Article in English | MEDLINE | ID: mdl-31954596

ABSTRACT

Especially in immunocompromised and intensive care patients VRE sepsis is associated with high mortality. The GeneXpert vanA/vanB assay is marketed for fast molecular surveillance of VRE colonization in peri-anal and rectal swabs. The aim of this study was to evaluate this assay for its usefulness for rapid identification of the vanAB determinant from positive blood cultures. During an evaluation phase, 33/34 blood cultures (negative = 13; vanA = 1; and vanB = 19) were correctly identified. In the validation phase 205/211 blood cultures were correctly identified (negative, n = 160; vanA, n = 2; vanB, n = 43). Sensitivity and specificity calculated from valid tests was 100% (95% CI: 90.2-100%) and 100% (95% CI: 97.1-100%), respectively. The error rate was 2.8%. The Xpert vanA/vanB cartridge is a reliable tool in the rapid molecular identification of the vanA and vanB determinant from positive blood cultures with moderate inhibition rates (2.8%) and high PPV and NPV. However, additional methods for species identification are required.


Subject(s)
Blood Culture , Gram-Positive Bacterial Infections/microbiology , Molecular Diagnostic Techniques/methods , Vancomycin-Resistant Enterococci/genetics , Bacterial Proteins/genetics , Germany , Gram-Positive Bacterial Infections/blood , Gram-Positive Bacterial Infections/diagnosis , Humans , Molecular Diagnostic Techniques/instrumentation , Prospective Studies , Rectum/microbiology , Sensitivity and Specificity , Tertiary Care Centers , Vancomycin Resistance , Vancomycin-Resistant Enterococci/isolation & purification
6.
J Virol ; 90(20): 9018-28, 2016 10 15.
Article in English | MEDLINE | ID: mdl-27466424

ABSTRACT

UNLABELLED: HIV-1 establishes a pool of latently infected cells early following infection. New therapeutic approaches aiming at diminishing this persisting reservoir by reactivation of latently infected cells are currently being developed and tested. However, the reactivation kinetics of viral mRNA and viral protein production, and their respective consequences for phenotypical changes in infected cells that might enable immune recognition, remain poorly understood. We adapted a novel approach to assess the dynamics of HIV-1 mRNA and protein expression in latently and newly infected cells on the single-cell level by flow cytometry. This technique allowed the simultaneous detection of gagpol mRNA, intracellular p24 Gag protein, and cell surface markers. Following stimulation of latently HIV-1-infected J89 cells with human tumor necrosis factor alpha (hTNF-α)/romidepsin (RMD) or HIV-1 infection of primary CD4(+) T cells, four cell populations were detected according to their expression levels of viral mRNA and protein. gagpol mRNA in J89 cells was quantifiable for the first time 3 h after stimulation with hTNF-α and 12 h after stimulation with RMD, while p24 Gag protein was detected for the first time after 18 h poststimulation. HIV-1-infected primary CD4(+) T cells downregulated CD4, BST-2, and HLA class I expression at early stages of infection, proceeding Gag protein detection. In conclusion, here we describe a novel approach allowing quantification of the kinetics of HIV-1 mRNA and protein synthesis on the single-cell level and phenotypic characterization of HIV-1-infected cells at different stages of the viral life cycle. IMPORTANCE: Early after infection, HIV-1 establishes a pool of latently infected cells, which hide from the immune system. Latency reversal and immune-mediated elimination of these latently infected cells are some of the goals of current HIV-1 cure approaches; however, little is known about the HIV-1 reactivation kinetics following stimulation with latency-reversing agents. Here we describe a novel approach allowing for the first time quantification of the kinetics of HIV-1 mRNA and protein synthesis after latency reactivation or de novo infection on the single-cell level using flow cytometry. This new technique furthermore enabled the phenotypic characterization of latently infected and de novo-infected cells dependent on the presence of viral RNA or protein.


Subject(s)
CD4-Positive T-Lymphocytes/virology , Cytological Techniques/methods , HIV-1/physiology , Virology/methods , Virus Activation , Cells, Cultured , Human Immunodeficiency Virus Proteins/analysis , Humans , RNA, Messenger/analysis , RNA, Viral/analysis , Time Factors
7.
J Virol ; 90(16): 7579-7586, 2016 08 15.
Article in English | MEDLINE | ID: mdl-27279617

ABSTRACT

UNLABELLED: HIV-1-infected individuals with protective HLA class I alleles exhibit better control of viremia and slower disease progression. Virus control in these individuals has been associated with strong and potent HIV-1-specific cytotoxic-T-lymphocyte (CTL) responses restricted by protective HLA alleles, but control of viremia also occurs in the presence of selected CTL escape mutations. CTL escape mutations restricted by protective HLA class I molecules are frequently located in the conserved p24 Gag sequence of HIV-1 that encodes the conical capsid core and have been suggested to reduce viral replication capacity. In this study, the consequences of well-described CTL-associated p24 Gag sequence mutations for HIV-1 capsid stability were assessed using a cyclosporine (CsA) washout assay. The frequently occurring HLA-B57- and HLA-B27-associated CTL escape mutations T242N and R264K resulted in delayed capsid uncoating, suggesting modulation of capsid stability. The described compensatory mutations L268M and S173A observed in R264K viruses reconstituted the capsid-uncoating half-time. Interestingly, capsid stability was correlated with infectivity. Taken together, these data demonstrate that CTL-driven escape mutations within p24 Gag restricted by protective HLA class I alleles have a significant impact on capsid stability that might contribute to the persistent control of viral replication observed despite viral escape from CTL responses. IMPORTANCE: Sequence mutations within p24 Gag selected by CTL responses restricted by protective HLA class I alleles have been associated with reduced viral fitness. However, the precise mechanisms underlying the reduced viral replication capacity and lower viral loads associated with these mutations remain unclear. Here, we demonstrate that dominant HLA-B27-associated CTL escape mutations within HIV-1 capsid lead to enhanced capsid rigidity, providing a possible mechanism for the reduced viral fitness of these variants.


Subject(s)
Capsid/immunology , Chemical Phenomena , HIV Core Protein p24/genetics , HIV-1/immunology , Mutation, Missense , Selection, Genetic , T-Lymphocytes, Cytotoxic/immunology , Capsid/chemistry , Capsid/physiology , HIV Core Protein p24/immunology , HIV-1/chemistry , HIV-1/genetics , HIV-1/physiology , Suppression, Genetic , Virus Uncoating
8.
J Clin Microbiol ; 52(5): 1751-3, 2014 May.
Article in English | MEDLINE | ID: mdl-24622094

ABSTRACT

A universal PCR assay for bacteria and fungi detected meningitis pathogens in 65% of 20 cerebrospinal fluid (CSF) samples from patients with suspected central nervous system (CNS) infections compared to a 35% detection rate by culture and/or microscopy methods. Thus, the PCR assay can improve the diagnosis rate of infective meningitis when standard methods provide a negative result.


Subject(s)
Bacterial Infections/diagnosis , Bacterial Infections/microbiology , Central Nervous System Infections/diagnosis , Central Nervous System Infections/microbiology , Polymerase Chain Reaction/methods , Bacteria/genetics , DNA, Bacterial/genetics , Humans , Meningitis, Bacterial/diagnosis , Meningitis, Bacterial/microbiology
9.
Zoonoses Public Health ; 58(8): 567-72, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21824358

ABSTRACT

Infection with sorbitol-fermenting Shiga toxin-producing Escherichia coli O157:H- (sf STEC O157:H-) is rare, but emerging in Europe. The pathogen is typically isolated from paediatric patients with life-threatening haemolytic uraemic syndrome (HUS). It is unclear whether this observation primarily reflects the pathogen's virulence or its complex laboratory diagnosis, not routinely conducted in diarrhoeal patients. In summer 2009, four boys living in the same suburb in Germany developed diarrhoea-associated HUS: three were infected by sf STEC O157:H- and one died. We conducted two analytical epidemiological studies, an extensive search for diarrhoeal cases in potentially exposed groups, and an environmental investigation. Outbreak cases were residents of the suburb diagnosed with HUS, sf STEC O157:H- infection, or both between 24 July 2009 and 25 August 2009. Overall, we ascertained eight cases with a median age of 4 years (range: from 8 months to 9 years). Stool screening of 220 persons led to the identification of only four additional cases: two asymptomatic carriers and two diarrhoeal cases. HUS was strongly associated with visiting a local playground in July, particularly on 16th July (odds ratio = 42.7, P = 0.002). No other commonality, including food, was identified, and all environmental samples (n = 24) were negative. In this localized non-foodborne outbreak, the place of likely infection was a local playground. Sf STEC O157:H- infection apparently limits itself rarely to diarrhoeal illness and progresses frequently to HUS. Therefore, detection of and response to this hypervirulent pathogen primarily relies on HUS surveillance.


Subject(s)
Diarrhea/microbiology , Escherichia coli Infections/complications , Escherichia coli Infections/epidemiology , Escherichia coli O157 , Hemolytic-Uremic Syndrome/epidemiology , Hemolytic-Uremic Syndrome/microbiology , Child , Child, Preschool , Diarrhea/complications , Diarrhea/epidemiology , Disease Outbreaks , Environmental Exposure/adverse effects , Escherichia coli O157/isolation & purification , Escherichia coli O157/pathogenicity , Feces/microbiology , Female , Germany/epidemiology , Hemolytic-Uremic Syndrome/complications , Humans , Infant , Interviews as Topic , Male , Play and Playthings , Risk Factors , Shiga-Toxigenic Escherichia coli , Sorbitol/metabolism
10.
Z Gastroenterol ; 48(9): 1126-32, 2010 Sep.
Article in German | MEDLINE | ID: mdl-20839162

ABSTRACT

BACKGROUND: The incidence of chronic hepatitis B in Germany is approximately 0.5 %. Data regarding knowledge about HBV, prevention behaviour and treatment adherence in patients with chronic HBV are scarce. METHODS: In this prospective study 201 consecutive patients with CHB infection were studied from a large urban academic outpatient clinic at the University Medical Centre in Hamburg. Patients were interviewed with a questionnaire that contained 47 questions covering social demographic dates, knowledge about HBV, treatment adherence and prevention. The success rate of interviews was 100 % with free translation service offered. RESULTS: 20.4 % of the CHB patients were born in Germany, but the majority of the patients were immigrants (80.6 %). 51 % of the patients had a good, 34 % a moderate and 15 % a poor knowledge about HBV. 89 % of the patients knew that HBV can be transmitted through blood contacts, but 34 % believed that inadequate hygienic conditions and 24 % that food products may transmit the virus. 96 % of the patients had knowledge about the existence of an HBV vaccine. Furthermore, 82 % considered a vaccination of all persons in the household important. Despite the knowledge of the existence and importance of a vaccine, only 61,7 % of the 300 affected children/siblings of HBV-positive family members were vaccinated. However, the child vaccination rate was significantly higher among patients with knowledge about the protective effect of the vaccine (p < 0.001), the free of charge vaccination program for children up to 18 years (p < 0.001) and higher school education (p < 0.001). Migrants with poor German language skills had lower knowledge scores (p < 0.001) and showed lower vaccination rates (p = 0.016) compared to immigrants with good German language skills. 43 % of all patients were treated with nucleot(s)ide analogues with a median treatment duration of 2 - 5 years. 65 % of these patients declared to never have missed a dose and 27 % missed less than one dose per month. 90 % of the patients tolerated the antiviral drugs very well and between patients with or without side effects there was no significant difference in quality of life. CONCLUSION: Chronic hepatitis B in Germany is characterised by awareness problems and language barriers. More attention is needed for HBV-infected immigrants in the form of multilingual information about CHB and awareness campaigns.


Subject(s)
Health Behavior , Health Knowledge, Attitudes, Practice , Hepatitis B, Chronic/epidemiology , Hepatitis B, Chronic/prevention & control , Patient Compliance/statistics & numerical data , Patient Education as Topic/statistics & numerical data , Referral and Consultation/statistics & numerical data , Adult , Emigrants and Immigrants/statistics & numerical data , Female , Germany/epidemiology , Humans , Male , Prevalence , Treatment Outcome
11.
J Clin Virol ; 34 Suppl 1: S54-62, 2005 Dec.
Article in English | MEDLINE | ID: mdl-16461225

ABSTRACT

Enormous progresses in hepatitis B virus research have been made through the identification of avian and mammalian HBV related viruses, which offer ample opportunities for studies in naturally occurring hosts. However, none of these natural hosts belongs to the commonly used laboratory animals, and the development of various mouse strains carrying HBV transgenes offered unique opportunities to investigate some mechanisms of viral pathogenesis. Furthermore, the need to perform infection studies in a system harbouring HBV-permissive hepatocytes has lately led researchers to create new challenging human mouse chimera models of HBV infection. In this review, we will overview the type of animal models currently available in hepadnavirus research.


Subject(s)
Hepatitis B virus/physiology , Hepatitis B/virology , Virus Replication , Animals , Disease Models, Animal , Hepatitis B/genetics , Hepatitis B virus/genetics , Liver Neoplasms, Experimental/virology , Mutation
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