Christos Hadjichristodoulou

Prof. Christos Hadjichristodoulou

Department of Hygiene & Epidemiology, Faculty of Medicine, University of Thessaly
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orcid

Research Focus & Metrics

Academic Career Length

33Years (1994-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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16 August 2018 in Eurosurveillance
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Journal Article
Open access
PNPatricia Ndumbi
Patricia Ndumbi
GFGudrun S Freidl
Gudrun S Freidl
CWChristopher J Williams
Christopher J Williams
OMOtilia Mårdh
Otilia Mårdh
CVCarmen Varela
Carmen Varela
MTMembers of the European Hepatitis A Outbreak Investigation Team
Members of the European Hepatitis A Outbreak Investigation Team
Between 1 June 2016 and 31 May 2017, 17 European Union (EU) and European Economic Area countries reported 4,096 cases associated with a multi-country hepatitis A (HA) outbreak. Molecular analysis identified three co-circulating hepatitis A virus (HAV) strains of genotype IA: VRD_521_2016, V16–25801 and RIVM-HAV16–090. We categorised cases as confirmed, probable or possible, according to the EU outbreak case definitions. Confirmed cases were infected with one of the three outbreak strains. We investigated case characteristics and strain-specific risk factors for transmission. A total of 1,400 (34%) cases were confirmed; VRD_521_2016 and RIVM-HAV16–090 accounted for 92% of these. Among confirmed cases with available epidemiological data, 92% (361/393) were unvaccinated, 43% (83/195) travelled to Spain during the incubation period and 84% (565/676) identified as men who have sex with men (MSM). Results depict an HA outbreak of multiple HAV strains, within a cross-European population, that was particularly driven by transmission between non-immune MSM engaging in high-risk sexual behaviour. The most effective preventive measure to curb this outbreak is HAV vaccination of MSM, supplemented by primary prevention campaigns that target the MSM population and promote protective sexual behaviour.

1 February 2018 in Food Microbiology
Verified
Journal Article
Closed access
PPPanagiotis Papadopoulos
Panagiotis Papadopoulos
TPTheofilos Papadopoulos
Theofilos Papadopoulos
AAApostolos S. Angelidis
Apostolos S. Angelidis
EBEvridiki Boukouvala
Evridiki Boukouvala
AZAntonios Zdragas
Antonios Zdragas
DSDaniel Sergelidis
Daniel Sergelidis

22 September 2021 in Nature
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Journal Article
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HBHamsa Bastani
Hamsa Bastani
KDKimon Drakopoulos
Kimon Drakopoulos
VGVishal Gupta
Vishal Gupta
IVIoannis Vlachogiannis
Ioannis Vlachogiannis
Christos HadjichristodoulouChristos Hadjichristodoulou
Christos Hadjichristodoulou
Sotirios TsiodrasSotirios Tsiodras
Sotirios Tsiodras

1 August 2015 in Antimicrobial Agents and Chemotherapy
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Journal Article
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KDKonstantina Dafopoulou
Konstantina Dafopoulou
OZOlympia Zarkotou
Olympia Zarkotou
EDEvangelia Dimitroulia
Evangelia Dimitroulia
Christos HadjichristodoulouChristos Hadjichristodoulou
Christos Hadjichristodoulou
VGVasiliki Gennimata
Vasiliki Gennimata
Athanasios TsakrisAthanasios Tsakris
Athanasios Tsakris
We compared six colistin susceptibility testing (ST) methods on 61 carbapenem-nonsusceptible Klebsiella pneumoniae ( n = 41) and Acinetobacter baumannii ( n = 20) clinical isolates with provisionally elevated colistin MICs by routine ST. Colistin MICs were determined by broth microdilution (BMD), BMD with 0.002% polysorbate 80 (P80) (BMD-P80), agar dilution (AD), Etest, Vitek2, and MIC test strip (MTS). BMD was used as the reference method for comparison. The EUCAST-recommended susceptible and resistant breakpoints of ≤2 and >2 μg/ml, respectively, were applied for both K. pneumoniae and A. baumannii . The proportions of colistin-resistant strains were 95.1, 77, 96.7, 57.4, 65.6, and 98.4% by BMD, BMD-P80, AD, Etest, MTS, and Vitek2, respectively. The Etest and MTS methods produced excessive rates of very major errors (VMEs) (39.3 and 31.1%, respectively), while BMD-P80 produced 18% VMEs, AD produced 3.3% VMEs, and Vitek2 produced no VMEs. Major errors (MEs) were rather limited by all tested methods. These data show that gradient diffusion methods may lead to inappropriate colistin therapy. Clinical laboratories should consider the use of automated systems, such as Vitek2, or dilution methods for colistin ST.

3 August 2020 in Metabolites
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Journal Article
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MKMichalis Koureas
Michalis Koureas
PKParaskevi Kirgou
Paraskevi Kirgou
Grigoris AmoutziasGrigoris Amoutzias
Grigoris Amoutzias
Christos HadjichristodoulouChristos Hadjichristodoulou
Christos Hadjichristodoulou
Konstantinos I. GourgoulianisKonstantinos I. Gourgoulianis
Konstantinos I. Gourgoulianis
Andreas TsakalofAndreas Tsakalof
Andreas Tsakalof
The aim of the present study was to investigate the ability of breath analysis to distinguish lung cancer (LC) patients from patients with other respiratory diseases and healthy people. The population sample consisted of 51 patients with confirmed LC, 38 patients with pathological computed tomography (CT) findings not diagnosed with LC, and 53 healthy controls. The concentrations of 19 volatile organic compounds (VOCs) were quantified in the exhaled breath of study participants by solid phase microextraction (SPME) of the VOCs and subsequent gas chromatography-mass spectrometry (GC-MS) analysis. Kruskal–Wallis and Mann–Whitney tests were used to identify significant differences between subgroups. Machine learning methods were used to determine the discriminant power of the method. Several compounds were found to differ significantly between LC patients and healthy controls. Strong associations were identified for 2-propanol, 1-propanol, toluene, ethylbenzene, and styrene (p-values < 0.001–0.006). These associations remained significant when ambient air concentrations were subtracted from breath concentrations. VOC levels were found to be affected by ambient air concentrations and a few by smoking status. The random forest machine learning algorithm achieved a correct classification of patients of 88.5% (area under the curve—AUC 0.94). However, none of the methods used achieved adequate discrimination between LC patients and patients with abnormal computed tomography (CT) findings. Biomarker sets, consisting mainly of the exogenous monoaromatic compounds and 1- and 2- propanol, adequately discriminated LC patients from healthy controls. The breath concentrations of these compounds may reflect the alterations in patient’s physiological and biochemical status and perhaps can be used as probes for the investigation of these statuses or normalization of patient-related factors in breath analysis.

1 August 2007 in PLOS ONE
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Athanasios MichosAthanasios Michos
Athanasios Michos
VSVasiliki Syriopoulou
Vasiliki Syriopoulou
Christos HadjichristodoulouChristos Hadjichristodoulou
Christos Hadjichristodoulou
GDGeorge L. Daikos
George L. Daikos
ELEvagelia Lagona
Evagelia Lagona
MTMaria Theodoridou
Maria Theodoridou
Non-polio human enteroviruses are the leading cause of aseptic meningitis in children. The role of enterovirus PCR for diagnosis and management of aseptic meningitis has not been fully explored. A retrospective study was conducted to determine the epidemiological, clinical, and laboratory characteristics of aseptic meningitis and to evaluate the role of enterovirus PCR for the diagnosis and management of this clinical entity. The medical records of children who had as discharge diagnosis aseptic or viral meningitis were reviewed. A total of 506 children, median age 5 years, were identified. The annual incidence rate was estimated to be 17/100,000 children less than 14 years of age. Most of the cases occurred during summer (38%) and autumn (24%). The dominant clinical symptoms were fever (98%), headache (94%) and vomiting (67%). Neck stiffness was noted in 60%, and irritation in 46% of the patients. The median number of CSF cell count was 201/mm3 with polymorphonuclear predominance (>50%) in 58.3% of the cases. Enterovirus RNA was detected in CSF in 47 of 96 (48.9%) children tested. Children with positive enterovirus PCR had shorter hospitalization stay as compared to children who had negative PCR or to children who were not tested (P = 0.01). There were no serious complications or deaths. Enteroviruses accounted for approximately one half of cases of aseptic meningitis. PCR may reduce the length of hospitalization and plays important role in the diagnosis and management of children with aseptic meningitis.