253 research outputs found
Reply to: “Similar risk of hepatocellular carcinoma during long-term entecavir or tenofovir therapy in Caucasian patients with chronic hepatitis B”
No full textSchool closure is currently the main strategy to mitigate influenza A(H1N1)v: a modeling study
No full textConcerns about an imminent influenza pandemic have been intensified after the emergence of the new influenza A(H1N1)v strain. Mathematical modeling was employed on recent epidemiological data from Mexico in order to assess the impact of intervention strategies on the spread of influenza A(H1N1)v in the setting of the European region. When initiating the intervention of 100% school closure in a community of 2,000 people at a threshold of 1% cumulative attack rate, the total number of symptomatic cases is predicted to decrease by 89.3%, as compared to the non-intervention scenario. When this measure is coupled with treatment and home isolation of symptomatic cases as well as a 50% reduction of social contacts, a 94.8% decline in the cumulative attack rate is predicted along with a much shorter duration of influenza A(H1N1)v transmission. Active surveillance that will ensure timely treatment and home isolation of symptomatic cases in combination with school closure seem to form an efficient strategy to control the spread of influenza A(H1N1)v.
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Assessing the impact of biomedical research in academic institutions of disparate sizes
No full textBackground. The evaluation of academic research performance is nowadays a priority issue. Bibliometric indicators such as the number of publications, total citation counts and h-index are an indispensable tool in this task but their inherent association with the size of the research output may result in rewarding high production when evaluating institutions of disparate sizes. The aim of this study is to propose an indicator that may facilitate the comparison of institutions of disparate sizes. Methods. The Modified Impact Index (MII) was defined as the ratio of the observed h-index (h) of an institution over the h-index anticipated for that institution on average, given the number of publications (N) it produces i.e. ( and denote the intercept and the slope, respectively, of the line describing the dependence of the h-index on the number of publications in log10 scale). MII values higher than 1 indicate that an institution performs better than the average, in terms of its h-index. Data on scientific papers published during 20022006 and within 36 medical fields for 219 Academic Medical Institutions from 16 European countries were used to estimate and and to calculate the MII of their total and field-specific production. Results. From our biomedical research data, the slope governing the dependence of h-index on the number of publications in biomedical research was found to be similar to that estimated in other disciplines (0.4). The MII was positively associated with the average number of citations/publication (r = 0.653, p < 0.001), the h-index (r = 0.213, p = 0.002), the number of publications with 100 citations (r = 0.211, p = 0.004) but not with the number of publications (r = -0.020, p = 0.765). It was the most highly associated indicator with the share of country-specific government budget appropriations or outlays for research and development as % of GDP in 2004 (r = 0.229) followed by the average number of citations/publication (r = 0.153) whereas the corresponding correlation coefficient for the h-index was close to 0 (r = 0.029). MII was calculated for first 10 top-ranked European universities in life sciences and biomedicine, as provided by Times Higher Education ranking system, and their total and field-specific performance was compared. Conclusion. The MII should complement the use of h-index when comparing the research output of institutions of disparate sizes. It has a conceptual interpretation and, with the data provided here, can be computed for the total research output as well as for field-specific publication sets of institutions in biomedicine. © 2009 Sypsa and Hatzakis
Incidence of liver- and non-liver-related outcomes in patients with HCV-cirrhosis after SVR
No full textBackground & aims: As the long-term benefits of a sustained virological response (SVR) in HCV-related cirrhosis following direct-acting antiviral (DAA) treatment remain undefined, we assessed the incidence and predictors of liver-related events (LREs), non-liver-related events (NLREs) and mortality in DAA-treated patients with cirrhosis.
Methods: Consecutive patients with cirrhosis and SVR were enrolled in a longitudinal, single-center study, and divided into 3 cohorts: Cohort A (Child-Pugh A without a previous LRE), Cohort B (Child-Pugh B or Child-Pugh A with prior non-hepatocellular carcinoma [HCC] LREs), Cohort C (previous HCC).
Results: A total of 636 patients with cirrhosis (median 65 years-old, 58% males, 89% Child-Pugh A) were followed for 51 (8-68) months (Cohort A n = 480, Cohort B n = 89, Cohort C n = 67). The 5-year estimated cumulative incidences of LREs were 10.4% in Cohort A vs. 32.0% in Cohort B (HCC 7.7% vs. 19.7%; ascites 1.4% vs. 8.6%; variceal bleeding 1.3% vs. 7.8%; encephalopathy 0 vs. 2.5%) vs. 71% in Cohort C (HCC only) (p <0.0001). The corresponding figures for NLREs were 11.7% in Cohort A vs. 17.9% in Cohort B vs. 17.5% in Cohort C (p = 0.32). The 5-year estimated probabilities of liver-related vs. non-liver-related deaths were 0.5% vs. 4.5% in Cohort A, 16.2% vs. 8.8% in Cohort B and 12.1% vs. 7.7% in Cohort C. The all-cause mortality rate in Cohort A was similar to the rate expected for the general population stratified by age, sex and calendar year according to the Human Mortality Database, while it was significantly higher in Cohort B.
Conclusions: Patients with cirrhosis and an SVR on DAAs face risks of liver-related and non-liver-related events and mortality; however, their incidence is strongly influenced by pre-DAA patient history.
Lay summary: In this large single-center study enrolling patients with hepatitis C virus (HCV)-related cirrhosis cured by direct-acting antivirals, pre-treatment liver disease history strongly influenced long-term outcomes. In patients with HCV-related cirrhosis, hepatocellular carcinoma was the most frequent liver-related complication after viral cure. Due to improved long-term outcomes, patients with cirrhosis after HCV cure are exposed to a significant proportion of non-liver-related events
Transmission dynamics of carbapenemase-producing Klebsiella pneumoniae and anticipated impact of infection control strategies in a surgical unit
No full textBackground: Carbapenemase-producing Klebsiella pneumoniae (CPKP) has been established as important nosocomial pathogen in many geographic regions. Transmission from patient to patient via the hands of healthcare workers is the main route of spread in the acute-care setting. Methodology/Principal Findings: Epidemiological and infection control data were recorded during a prospective observational study conducted in a surgical unit of a tertiary-care hospital in Greece. Surveillance culture for CPKP were obtained from all patients upon admission and weekly thereafter. The Ross-Macdonald model for vector-borne diseases was applied to obtain estimates for the basic reproduction number R0 (average number of secondary cases per primary case in the absence of infection control) and assess the impact of infection control measures on CPKP containment in endemic and hyperendemic settings. Eighteen of 850 patients were colonized with CPKP on admission and 51 acquired CPKP during hospilazation. R0 reached 2 and exceeded unity for long periods of time under the observed hand hygiene compliance (21%). The minimum hand hygiene compliance level necessary to control transmission was 50%. Reduction of 60% to 90% in colonized patients on admission, through active surveillance culture, contact precautions and isolation/cohorting, in combination with 60% compliance in hand hygiene would result in rapid decline in CPKP prevalence within 8-12 weeks. Antibiotics restrictions did not have a substantial benefit when an aggressive control strategy was implemented. Conclusions/Significance: Surveillance culture on admission and isolation/cohorting of colonized patients coupled with moderate hand hygiene compliance and contact precautions may lead to rapid control of CPKP in endemic and hyperendemic healthcare settings. © 2012 Sypsa et al
Food insecurity among people who inject drugs in Athens, Greece: A study in the context of ARISTOTLE programme
No full textObjective: To measure the prevalence of food insecurity and explore related characteristics and behaviours among people who inject drugs (PWID). Design: Cross-sectional analysis of a community-based programme for HIV infection among PWID (ARISTOTLE programme). Food insecurity was measured by the Household Food Insecurity Access Scale. Computer-assisted interviews and blood samples were also collected. Setting: A fixed location in Athens Metropolitan Area, Greece, during 2012-2013. Participants: In total, 2834 unique participants with history of injecting drug use in the past 12 months were recruited over four respondent-driven sampling rounds (approximately 1400/round). Results: More than 50 % of PWID were severely or moderately food insecure across all rounds. PWID were more likely to be severely food insecure if they were older than 40 years [adjusted OR (aOR): 1.71, 95 % CI: 1.33-2.19], were women (aOR: 1.49, 95 % CI: 1.17-1.89), from Middle East countries (aOR v. from Greece: 1.80, 95 % CI: 1.04-3.11), had a lower educational level (primary or secondary school v. higher education; aOR: 1.54, 95 % CI: 1.29-1.84), had no current health insurance (aOR: 1.45, 95 % CI: 1.21-1.73), were homeless (aOR: 17.1, 95 % CI: 12.3-23.8) or were living with another drug user (aOR: 1.55, 95 % CI: 1.26-1.91) as compared with those living alone or with family/friends. HIV-infected PWID were more likely to be severely food insecure compared with uninfected (59.0 % v. 51.0 %, respectively, P = 0.002); however, this difference was attributed to the confounding effect of homelessness. Conclusions: Moderate/severe food insecurity was a significant problem, reaching > 50 % in this sample of PWID and closely related to socio-demographic characteristics and especially homelessness. © Authors 2020
Transmission Potential of Human Monkeypox in Mass Gatherings
No full textSince May 2022, a large number of monkeypox cases have been reported in Europe, the United States, and other nonendemic settings. Taking into account the strict measures implemented due to the coronavirus disease 2019 pandemic and the desire of people to reclaim what is perceived as lost time, mass gatherings this summer were highly attended. Based on data for the secondary attack rate among unvaccinated contacts from endemic countries, we estimate that, on average, >1 secondary case is anticipated per infectious person if he/she has a high number of group contacts (>30) or >8 close contacts. Although the role of group contacts in mass gatherings is uncertain (less likely to involve physical contact, shorter duration), close contacts associated with the event (eg, intimate/sexual contact with other attendees) might be the amplifying event. Enforcing awareness, early recognition, and engaging affected populations in the monkeypox response are important to control transmission. © 2022 The Author(s). Published by Oxford University Press on behalf of Infectious Diseases Society of America
Estimating the disease Burden of 2009 pandemic influenza a(H1N1) from surveillance and household surveys in Greece
No full textBackground: The aim of this study was to assess the disease burden of the 2009 pandemic influenza A(H1N1) in Greece. Methodology/Principal Findings: Data on influenza-like illness (ILI), collected through cross-sectional nationwide telephone surveys of 1,000 households in Greece repeated for 25 consecutive weeks, were combined with data from H1N1 virologic surveillance to estimate the incidence and the clinical attack rate (CAR) of influenza A(H1N1). Alternative definitions of ILI (cough or sore throat and fever>38°C [ILI-38] or fever 37.1-38°C [ILI-37]) were used to estimate the number of symptomatic infections. The infection attack rate (IAR) was approximated using estimates from published studies on the frequency of fever in infected individuals. Data on H1N1 morbidity and mortality were used to estimate ICU admission and case fatality (CFR) rates. The epidemic peaked on week 48/2009 with approximately 750-1,500 new cases/100,000 population per week, depending on ILI-38 or ILI-37 case definition, respectively. By week 6/2010, 7.1%-15.6% of the population in Greece was estimated to be symptomatically infected with H1N1. Children 5-19 years represented the most affected population group (CAR:27%-54%), whereas individuals older than 64 years were the least affected (CAR:0.6%-2.2%). The IAR (95% CI) of influenza A(H1N1) was estimated to be 19.7% (13.3%, 26.1%). Per 1,000 symptomatic cases, based on ILI-38 case definition, 416 attended health services, 108 visited hospital emergency departments and 15 were admitted to hospitals. ICU admission rate and CFR were 37 and 17.5 per 100,000 symptomatic cases or 13.4 and 6.3 per 100,000 infections, respectively. Conclusions/Significance: Influenza A(H1N1) infected one fifth and caused symptomatic infection in up to 15% of the Greek population. Although individuals older than 65 years were the least affected age group in terms of attack rate, they had 55 and 185 times higher risk of ICU admission and CFR, respectively. © 2011 Sypsa et al
Schematic representation of the S(V)EIR epidemic model for the baseline scenario of immunity waning.
No full textSchematic representation of the S(V)EIR epidemic model for the baseline scenario of immunity waning.</p
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