Udo Buchholz
Robert Koch Institute
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The New England Journal of Medicine | 2011
Christina Frank; Dirk Werber; Jakob P. Cramer; Mona Askar; Mirko Faber; Helen Bernard; Angelika Fruth; Rita Prager; Anke Spode; Maria Wadl; Alexander Zoufaly; Sabine Jordan; Markus J. Kemper; Per Follin; Luise Müller; Lisa A. King; Bettina Rosner; Udo Buchholz; Klaus Stark; Gérard Krause
BACKGROUND We describe an outbreak of gastroenteritis and the hemolytic-uremic syndrome caused by Shiga-toxin-producing Escherichia coli in Germany in May, June, and July, 2011. The consumption of sprouts was identified as the most likely vehicle of infection. METHODS We analyzed data from reports in Germany of Shiga-toxin-producing E. coli gastroenteritis and the hemolytic-uremic syndrome and clinical information on patients presenting to Hamburg University Medical Center (HUMC). An outbreak case was defined as a reported case of the hemolytic-uremic syndrome or of gastroenteritis in a patient infected by Shiga-toxin-producing E. coli, serogroup O104 or serogroup unknown, with an onset of disease during the period from May 1 through July 4, 2011, in Germany. RESULTS A total of 3816 cases (including 54 deaths) were reported in Germany, 845 of which (22%) involved the hemolytic-uremic syndrome. The outbreak was centered in northern Germany and peaked around May 21 to 22. Most of the patients in whom the hemolytic-uremic syndrome developed were adults (88%; median age, 42 years), and women were overrepresented (68%). The estimated median incubation period was 8 days, with a median of 5 days from the onset of diarrhea to the development of the hemolytic-uremic syndrome. Among 59 patients prospectively followed at HUMC, the hemolytic-uremic syndrome developed in 12 (20%), with no significant differences according to sex or reported initial symptoms and signs. The outbreak strain was typed as an enteroaggregative Shiga-toxin-producing E. coli O104:H4, producing extended-spectrum beta-lactamase. CONCLUSIONS In this outbreak, caused by an unusual E. coli strain, cases of the hemolytic-uremic syndrome occurred predominantly in adults, with a preponderance of cases occurring in women. The hemolytic-uremic syndrome developed in more than 20% of the identified cases.
Emerging Infectious Diseases | 2002
Stef L.A.M. Bronzwaer; Otto Cars; Udo Buchholz; Sigvard Mölstad; Wim G Goettsch; Irene K. Veldhuijzen; Jacobus Leen Kool; Marc Sprenger; John E. Degener
In Europe, antimicrobial resistance has been monitored since 1998 by the European Antimicrobial Resistance Surveillance System (EARSS). We examined the relationship between penicillin nonsusceptibility of invasive isolates of Streptococcus pneumoniae (an indicator organism) and antibiotic sales. Information was collected on 1998-99 resistance data for invasive isolates of S. pneumoniae to penicillin, based on surveillance data from EARSS and on outpatient sales during 1997 for beta-lactam antibiotics and macrolides. Our results show that in Europe antimicrobial resistance is correlated with use of beta-lactam antibiotics and macrolides.
American Journal of Epidemiology | 2010
Thorsten Suess; Udo Buchholz; Susann Dupke; Roland Grunow; Matthias an der Heiden; Alla Heider; Barbara Biere; Brunhilde Schweiger; Walter Haas; Gérard Krause
Essential epidemiologic and virologic parameters must be measured to provide evidence for policy/public health recommendations and mathematical modeling concerning novel influenza A/H1N1 virus (NIV) infections. Therefore, from April through August of 2009, the authors collected nasopharyngeal specimens and information on antiviral medication and symptoms from households with NIV infection on a daily basis in Germany. Specimens were analyzed quantitatively by using reverse transcriptase-polymerase chain reaction. In 36 households with 83 household contacts, 15 household contacts became laboratory-confirmed secondary cases of NIV. Among 47 contacts without antiviral prophylaxis, 12 became cases (secondary attack rate of 26%), and 1 (8%) of these was asymptomatic. The mean and median serial interval were 2.6 and 3 days, respectively (range: 1-3 days). On average, the authors detected viral RNA copies for 6.6 illness days (treated in time = 5.7 days, not treated in time = 7.1 days; P = 0.06), but they estimated that most patients cease to excrete viable virus by the fifth illness day. Shedding profiles were consistent with the number and severity of symptoms. Compared with other nasopharyngeal specimen types, nasal wash was the most sensitive. These results support the notion that epidemiologic and virologic characteristics of NIV are in many aspects similar to those of seasonal influenza.
Eurosurveillance | 2014
Esther Kissling; Marta Valenciano; Udo Buchholz; Amparo Larrauri; Jean-Marie Cohen; Baltazar Nunes; J. Rogalska; Daniela Pitigoi; Iwona Paradowska-Stankiewicz; Annicka Reuss; Silvia Jiménez-Jorge; I. Daviaud; Raquel Guiomar; Joan O’Donnell; Gheorghe Necula; M. Głuchowska; A. Moren
In the fifth season of Influenza Monitoring Vaccine Effectiveness in Europe (I-MOVE), we undertook a multicentre case-control study (MCCS) in seven European Union (EU) Member States to measure 2012/13 influenza vaccine effectiveness against medically attended influenza-like illness (ILI) laboratory confirmed as influenza. The season was characterised by substantial co-circulation of influenza B, A(H1N1)pdm09 and A(H3N2) viruses. Practitioners systematically selected ILI patients to swab ≤7 days of symptom onset. We compared influenza-positive by type/subtype to influenza-negative patients among those who met the EU ILI case definition. We conducted a complete case analysis using logistic regression with study as fixed effect and calculated adjusted vaccine effectiveness (AVE), controlling for potential confounders (age, sex, symptom onset week and presence of chronic conditions). We calculated AVE by type/subtype. Study sites sent 7,954 ILI/acute respiratory infection records for analysis. After applying exclusion criteria, we included 4,627 ILI patients in the analysis of VE against influenza B (1,937 cases), 3,516 for A(H1N1)pdm09 (1,068 cases) and 3,340 for influenza A(H3N2) (730 cases). AVE was 49.3% (95% confidence interval (CI): 32.4 to 62.0) against influenza B, 50.4% (95% CI: 28.4 to 65.6) against A(H1N1)pdm09 and 42.2% (95% CI: 14.9 to 60.7) against A(H3N2). Our results suggest an overall low to moderate AVE against influenza B, A(H1N1)pdm09 and A(H3N2), between 42 and 50%. In this season with many co-circulating viruses, the high sample size enabled stratified AVE by type/subtype. The low estimates indicate seasonal influenza vaccines should be improved to achieve acceptable protection levels.
Influenza and Other Respiratory Viruses | 2013
Helge Hollmeyer; Frederick G. Hayden; Anthony W. Mounts; Udo Buchholz
Please cite this paper as: Hollmeyer et al. (2012) Review: interventions to increase influenza vaccination among healthcare workers in hospitals. Influenza and Other Respiratory Viruses 7(4), 604–621.
PLOS ONE | 2012
Thorsten Suess; Cornelius Remschmidt; Susanne Schink; Brunhilde Schweiger; Alla Heider; Jeanette Milde; Andreas Nitsche; Kati Schroeder; Joerg Doellinger; Christian T. Braun; Walter Haas; Gérard Krause; Udo Buchholz
Background Influenza viral shedding studies provide fundamental information for preventive strategies and modelling exercises. We conducted a prospective household study to investigate viral shedding in seasonal and pandemic influenza between 2007 and 2011 in Berlin and Munich, Germany. Methods Study physicians recruited index patients and their household members. Serial nasal specimens were obtained from all household members over at least eight days and tested quantitatively by qRT-PCR for the influenza virus (sub)type of the index patient. A subset of samples was also tested by viral culture. Symptoms were recorded daily. Results We recruited 122 index patients and 320 household contacts, of which 67 became secondary household cases. Among all 189 influenza cases, 12 were infected with seasonal/prepandemic influenza A(H1N1), 19 with A(H3N2), 60 with influenza B, and 98 with A(H1N1)pdm09. Nine (14%) of 65 non-vaccinated secondary cases were asymptomatic/subclinical (0 (0%) of 21 children, 9 (21%) of 44 adults; p = 0.03). Viral load among patients with influenza-like illness (ILI) peaked on illness days 1, 2 or 3 for all (sub)types and declined steadily until days 7–9. Clinical symptom scores roughly paralleled viral shedding dynamics. On the first day prior to symptom onset 30% (12/40) of specimens were positive. Viral load in 6 asymptomatic/subclinical patients was similar to that in ILI-patients. Duration of infectiousness as measured by viral culture lasted approximately until illness days 4–6. Viral load did not seem to be influenced by antiviral therapy, age or vaccination status. Conclusion Asymptomatic/subclinical infections occur infrequently, but may be associated with substantial amounts of viral shedding. Presymptomatic shedding may arise in one third of cases, and shedding characteristics appear to be independent of (seasonal or pandemic) (sub)type, age, antiviral therapy or vaccination; however the power to find moderate differences was limited.
Emerging Themes in Epidemiology | 2005
Phillip Zucs; Udo Buchholz; Walter Haas; Helmut Uphoff
Influenza-associated excess mortality is widely used to assess the severity of influenza epidemics. In Germany, however, it is not yet established as a routine component of influenza surveillance. We therefore applied a simple method based on the annual distribution of monthly relative mortality (relative mortality distribution method, RMDM) to a time-series of German monthly all-cause mortality data from 1985–2001 to estimate influenza-associated excess mortality. Results were compared to those obtained by cyclical regression.Both methods distinguished stronger from milder influenza seasons, but RMDM gave the better fit (R2 = 0.80). For the years after reunification, i.e. 1990/91 through 2000/01, RMDM yielded an average of 6900 (conservative estimate) to13600 influenza-asssociated excess deaths per season (crude estimate). The most severe epidemics occurred during subtype A/H3N2 seasons. While German all-cause mortality declined over the study period, the number of excess deaths displayed an upward trend, coinciding with an increase of the proportion of the elderly population.
BMC Infectious Diseases | 2010
Christopher J. Williams; Brunhilde Schweiger; Genia Diner; Frank Gerlach; Frank Haaman; Gérard Krause; Albert Nienhaus; Udo Buchholz
BackgroundInfluenza immunisation for healthcare workers is encouraged to protect their often vulnerable patients but also due to a perceived higher risk for influenza. We aimed to compare the risk of influenza infection in healthcare workers in acute hospital care with that in non-healthcare workers over the same season.MethodsWe conducted a prospective, multicentre cohort study during the 2006/07 influenza season in Berlin, Germany. Recruited participants gave serum samples before and after the season, and completed questionnaires to determine their relevant exposures and possible confounding factors. The main outcome measure was serologically confirmed influenza infection (SCII), defined as a fourfold or greater rise in haemagglutination inhibition antibody titres to a circulating strain of influenza (with post-season titre at least 1:40).Weekly mobile phone text messages were used to prompt participants to report respiratory illnesses during the influenza season. A logistic regression model was used to assess the influence of potential risk factors.ResultsWe recruited 250 hospital healthcare workers (mean age 35.7 years) and 486 non-healthcare workers (mean age 39.2 years) from administrative centres, blood donors and colleges.Overall SCII attack rate was 10.6%. Being a healthcare worker was not a risk factor for SCII (relative risk 1.1, p = 0.70). The final multivariate model had three significant factors: living with children (odds ratio [OR] 3.7, p = 0.005), immunization (OR 0.50, p = 0.02), and - among persons living in households without children - ownership of a car (OR 3.0, p = 0.02). Living with three or more children (OR 13.8, p < 0.01) was a greater risk than living with one or two children (OR 5.3, p = 0.02). 30% of participants with SCII reported no respiratory illness. Healthcare workers were at slightly higher risk of reporting any respiratory infection than controls (adjusted OR 1.3, p = 0.04, n = 850).ConclusionsOur results suggest that healthcare workers in hospitals do not have a higher risk of influenza than non-healthcare workers, although their risk of any respiratory infection is slightly raised. Household contacts seem to be more important than exposure to patients. Car ownership is a surprise finding which needs further exploration. Asymptomatic infections are common, accounting for around a third of serologically confirmed infections.
BMC Infectious Diseases | 2012
Thorsten Suess; Cornelius Remschmidt; Susanne Schink; Brunhilde Schweiger; Andreas Nitsche; Kati Schroeder; Joerg Doellinger; Jeanette Milde; Walter Haas; Irina Koehler; Gérard Krause; Udo Buchholz
BackgroundPrevious controlled studies on the effect of non-pharmaceutical interventions (NPI) - namely the use of facemasks and intensified hand hygiene - in preventing household transmission of influenza have not produced definitive results. We aimed to investigate efficacy, acceptability, and tolerability of NPI in households with influenza index patients.MethodsWe conducted a cluster randomized controlled trial during the pandemic season 2009/10 and the ensuing influenza season 2010/11. We included households with an influenza positive index case in the absence of further respiratory illness within the preceding 14 days. Study arms were wearing a facemask and practicing intensified hand hygiene (MH group), wearing facemasks only (M group) and none of the two (control group). Main outcome measure was laboratory confirmed influenza infection in a household contact. We used daily questionnaires to examine adherence and tolerability of the interventions.ResultsWe recruited 84 households (30 control, 26 M and 28 MH households) with 82, 69 and 67 household contacts, respectively. In 2009/10 all 41 index cases had a influenza A (H1N1) pdm09 infection, in 2010/11 24 had an A (H1N1) pdm09 and 20 had a B infection. The total secondary attack rate was 16% (35/218). In intention-to-treat analysis there was no statistically significant effect of the M and MH interventions on secondary infections. When analysing only households where intervention was implemented within 36 h after symptom onset of the index case, secondary infection in the pooled M and MH groups was significantly lower compared to the control group (adjusted odds ratio 0.16, 95% CI, 0.03-0.92). In a per-protocol analysis odds ratios were significantly reduced among participants of the M group (adjusted odds ratio, 0.30, 95% CI, 0.10-0.94). With the exception of MH index cases in 2010/11 adherence was good for adults and children, contacts and index cases.ConclusionsResults suggest that household transmission of influenza can be reduced by the use of NPI, such as facemasks and intensified hand hygiene, when implemented early and used diligently. Concerns about acceptability and tolerability of the interventions should not be a reason against their recommendation.Trial registrationThe study was registered with ClinicalTrials.gov (Identifier NCT00833885).
Bone Marrow Transplantation | 2013
Nicola Lehners; Paul Schnitzler; Steffen Geis; J. Puthenparambil; M. A. Benz; B. Alber; T. Luft; Peter Dreger; Christoph Eisenbach; C. Kunz; A. Benner; Udo Buchholz; Elisabeth Aichinger; U. Frank; Klaus Heeg; Anthony D. Ho; Gerlinde Egerer
Respiratory syncytial virus (RSV) usually causes self-limiting upper respiratory tract infections, but can be associated with severe lower respiratory tract infection disease (LRTID) in infants and in patients with hematologic malignancies. We have analyzed the risk factors and the measures for containment within an outbreak of nosocomial RSV infections in a hematology and SCT unit. A total of 56 patients were affected (53 RSV-A and 3 RSV-B) including 32 transplant patients (16 allogeneic and 16 autologous). Forty (71%) of the 56 patients suffered from LRTID and 14 (35%) of the patients with LRTID subsequently died. However, because of concomitant infections with fungal and bacterial pathogens, the impact of RSV on the fatal outcome was difficult to assess. Multivariate analysis showed that low levels of IgG were significantly associated with fatal outcome (P=0.007), treatment with oral ribavirin represented a protective factor (P=0.02). An extremely protracted viral shedding was observed in this cohort of patients (median=30.5 days, range: 1–162 days), especially pronounced in patients after allogeneic transplantation (P=0.002). Implementation of rigorous isolation and barrier measures, although challenged by long-term viral carriers, was effective in containment of the outbreak.