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Q fever is a worldwide spread zoonotic disease, caused by the gram-negative intracellular bacillus Coxiella burnetii. Apart from its most common manifestations, Q fever has been reported to occasionally mimic autoimmune diseases. We herein present a case of acute Q fever in a 69-year-old man, manifesting as prolonged fever with pneumonitis, in whom biopsy of the temporal artery revealed giant cell arteritis. Moreover, PCR testing of the biopsy specimen was positive for Coxiella burnetii, thus further supporting the possibly infectious etiology of some cases of biopsy proven giant cell arteritis, with implications for treatment.

Snakebite envenoming is a major health issue in many parts of the world, especially in rural areas. Vipera ammodytes is the commonest cause of snakebite in Greece. We report our experience with a patient bitten by such a snake, who developed massive intravascular hemolysis characterized by a spherocytic rather than microangiopathic hemolytic picture. This case illustrates the potential of snakebite envenoming to cause spherocytic hemolytic anemia associated with hemoglobinuria and acute renal failure, and represents the first report of V. ammodytes in this context. Another important point is that antivenom was rapidly effective in reversing spherocytic hemolytic anemia, even though several hours had elapsed since the bite.

Human populations are chronically exposed to mixtures of toxic chemicals. Predicting the health effects of these mixtures require a large amount of information on the mode of action of their components. Xenobiotic metabolism by bacteria inhabiting the gastrointestinal tract has a major influence on human health. Our review aims to explore the literature for studies looking to characterize the different modes of action and outcomes of major chemical pollutants, and some components of cosmetics and food additives, on gut microbial communities in order to facilitate an estimation of their potential mixture effects. We identified good evidence that exposure to heavy metals, pesticides, nanoparticles, polycyclic aromatic hydrocarbons, dioxins, furans, polychlorinated biphenyls, and non-caloric artificial sweeteners affect the gut microbiome and which is associated with the development of metabolic, malignant, inflammatory, or immune diseases. Answering the question ‘Who is there?’ is not sufficient to define the mode of action of a toxicant in predictive modeling of mixture effects. Therefore, we recommend that new studies focus to simulate real-life exposure to diverse chemicals (toxicants, cosmetic/food additives), including as mixtures, and which combine metagenomics, metatranscriptomics and metabolomic analytical methods achieving in that way a comprehensive evaluation of effects on human health.

Hotel water systems colonized with Legionella spp. have been the source of travel-associated Legionnaires’ disease and cases, clusters or outbreaks continue to be reported worldwide each year. A total of 132 hotels linked with travel-associated Legionnaires’ disease, as reported through the European Legionnaires’ Disease Surveillance Network, were inspected and tested for Legionella spp. during 2000–2019 by the public health authorities of the island of Crete (Greece). A total of 3,311 samples were collected: 1,885 (56.93%) from cold water supply systems, 1,387 (41.89%) from hot water supply systems, 37 (1.12%) were swab samples and two (0.06%) were soil. Of those, 685 (20.69%), were collected from 83 (62.89%) hotels, testing positive (≥ 50CFU/L) for Legionella pneumophila) serogroups 1-10, 12-14 and non-pneumophila species (L. anisa, L. erythra, L. tusconensis, L. taurinensis, L. birminghamensis, L. rubrilucens, L. londiniesis, L. oakridgensis, L. santicrusis, L. brunensis, L. maceacherii). The most frequently isolated L. pneumophila serogroups were 1 (27.92%) and 3 (17.08%). Significantly higher isolation rates were obtained from hot water supply systems (25.96%) versus cold water systems (16.98%) and swab samples (13.51%). A Relative Risk (R.R.) > 1 (p < 0.0001) was calculated for hot water temperature

A predictive mathematical model describing the effect of temperature on the inactivation of Legionella pneumophila in water was developed. Thermal inactivation of L. pneumophila was monitored under isothermal conditions (51 - 61°C). A primary log-linear model was fitted to the inactivation data and the estimated D values ranged from 0.23 to 25.31 min for water temperatures from 61 to 51°C, respectively. The effect of temperature on L. pneumophila inactivation was described using a secondary model, and the model parameters z value and Dref (D-value at 55°C) were estimated at 5.54°C and 3.47 min, respectively. The developed model was further validated under dynamic temperature conditions mimicking various conditions of water thermal disinfection in plumbing systems. The results indicated that the model can satisfactorily predict thermal inactivation of the pathogen at dynamic temperature environments and effectively translate water temperature profiles to cell number reduction. The application of the model in combination with effective temperature monitoring could provide the basis of an integrated preventive approach for the effective control of L. pneumophila in plumbing systems.

The current systematic review investigates the antibiotic susceptibility pattern of Legionella pneumophila isolates from the 1980s to the present day, deriving data from clinical and/or water samples from studies carried out all over the world. Eighty-nine papers meeting the inclusion criteria, i.e., “Legionella pneumophila” and “resistance to antibiotics”, were evaluated according to pre-defined validity criteria. Sixty articles referred to clinical isolates, and 18 articles reported water-related L. pneumophila isolates, while 11 articles included both clinical and water isolates. Several methods have been proposed as suitable for the determination of MICs, such as the E-test, broth and agar dilution, and disk diffusion methods, in vivo and in vitro, using various media. The E-test method proposed by the European Society of Clinical Microbiology and Infectious Diseases (EUCAST) seems to be the second most frequently used method overall, but it is the preferred method in the most recent publications (2000–2019) for the interpretation criteria. Erythromycin has been proved to be the preference for resistance testing over the years. However, in the last 19 years, the antibiotics ciprofloxacin (CIP), erythromycin (ERM), levofloxacin (LEV) and azithromycin (AZM) were the ones that saw an increase in their use. A decrease in the sensitivity to antibiotics was identified in approximately half of the reviewed articles.

Testing for vector-borne pathogens in livestock is largely reliant upon blood and tissue. The role of biopsy samples remains poorly explored for detecting tick-borne bacteria in animals.In a 2-year survey, animals of veterinary importance from farms throughout the northern part of Greece were routinely checked for the presence of biopsy samples. Where detected, either a portion or a biopsy was collected together with whole blood samples and any ticks at the site of the biopsy sample. Molecular testing was carried out by real-time PCR targeting the internal transcribed spacer gene of Bartonella species. A total of 68 samples (28 blood samples, 28 biopsy samples and 12 ticks (nine Rhipicephalus bursa and three Rhipicephalus turanicus)) were collected from goats (64 samples) and cattle (four samples). Eight (11.8%) of the 68 samples were positive for Bartonella species. Of the biopsy and whole blood samples, four (14.3%) of each type were positive for Bartonella species. None of the ticks tested positive for Bartonella species. All pairs of positive biopsy samples/whole blood samples originated from the same animals. Positive samples were identified as Bartonella vinsonii subsp. arupensis. Although many more samples from a much wider spectrum of animal species is required before concluding upon the merit of biopsy samples in the study of tick-borne diseases, the significance of our finding warrants further study, both for clinical consequences in small ruminants and for those humans who are farming infected animals. Keywords: Animals of veterinary importance, Bartonella, biopsy sample, tick

The COVID-19 pandemic has urged many countries to issue new regulations to assure safety in pool environments. Greece enforced stricter requirements in 2020 and 2021 for hotel pools. However, even though regulations are important, they can only be effective when accepted by the pool managers and users. The aim of this study was to (a) assess the acceptability of the regulations by hotel managers; (b) assess compliance during the summer touristic periods in 2020 and 2021; and (c) identify challenges during the implementation of the regulations that need to be addressed. Several non-compliances from the regulations were identified. Continuous chlorination with an automatic chlorinator was not a regular practice and suggested water circulation rates were poorly met. The microbiological and chemical testing frequency of the pool water and keeping the number of bathers allowed per surface area in the pool were reported as the most difficult requirements to meet. Most pool managers agreed that new measures contribute to the pool users’ safety; however, they reported increased cost as the main impediment for their implementation. The modernization of regulations governing swimming pools’ function, in terms of risk assessment orientation, will contribute to the adoption of an integrated compliance strategy on emerging health issues, such as COVID-19.

The golden jackal (Canis aureus) is a medium-sized canid species native to Europe. This species is characterized by rapid large-scale expansion. A similar trend is also observed in Serbia, where the species is now distributed in more than a half of the territory. Although jackals prefer habitats in human-dominated landscapes, these animals have not been studied well enough from an eco-epidemiological point of view, and little is known about their potential for carrying zoonotic pathogens. In a study conducted during a three-year period (01/2010-02/2013), a total of 216 hunted or road-killed golden jackals were collected from 10 localities in Serbia. Ticks, when present, were removed, and after necropsy, spleen samples were collected from each animal. All tick and spleen samples were tested for the DNA of bacterial and protozoan tick-borne pathogens (Borrelia species, Bartonella species, Rickettsia species, Anaplasma species, Coxiella burnetii, Francisella species and Babesia species) by multiplex real-time PCR, conventional PCR and sequencing analyses. The DNA of Babesia canis was detected in nine out of 216 (4.2%) spleen samples, and two samples (0.9%) tested positive for Anaplasma phagocytophilum. In 118 ticks collected from jackals, the DNA of two Babesia species (Ba. canis and Ba. microti), three Borrelia species (Bo. garinii, Bo. valaisiana, and Bo. lusitaniae) and A. marginale was detected. From the aspect of public health surveillance, the potential role of the golden jackal in the maintenance of vector-borne zoonotic pathogens in Serbia must be considered, and further eco-epidemiological studies should be performed to determine the precise role of this animal species in zoonotic disease transmission cycles.

Despite the intensive implementation of control programmes goat, sheep and human brucellosis remains endemic in Greece. As the discrimination between field endemic strains and vaccine strain Rev.1 is not feasible, it is essential to develop new diagnostic tools for brucellosis diagnosis. Moreover, effective disease control requires enhanced epidemiological surveillance in both humans and animals including robust laboratory support. Two new multiplex (duplex) polymerase chain reactions (PCRs) were developed and the results were compared with those obtained by real‐time PCR and bacteriological biotyping. A total of 71 Brucella spp. Greek endemic strains were identified at species and biovar level, using both molecular and conventional techniques. Their discrimination from the vaccine strain Rev.1 was achieved, using polymerase chain reaction‐restriction fragment length polymorphism assay (PCR‐RFLP). All 71 strains were identified as Brucella melitensis by multiplex PCR as well as by real‐time PCR and conventional biotyping. Sixty‐two (87.3%) out of 71 strains were identified as B. melitensis biovar 3, eight (11,3%) strains as biovar 1 and only one (1,4%) as biovar 2. Digestion with PstI restriction enzyme revealed that all strains were field endemic strains, as they gave different patterns from the vaccine strain Rev.1. Brucella melitensis biovar 3 appears to be the predominant type in Greece. The novel multiplex PCR produced results concordant to ones obtained by real‐time PCR and conventional biotyping. This technique could support and facilitate the surveillance of Brucellosis in Greece contributing in the control of the disease.

Background Brucellosis remains a disease that is very difficult to control and eradicate in Greece. Information exchange between the responsible authorities is crucial in order to support public health infrastructure in the sense of the 'One-Health' strategy model. Methods The data for 2007-2012 were retrieved from the notifiable diseases system and analysed statistically for correlations between human brucellosis cases and the disease in small ruminants. Disease-related risk factors were also estimated with parallel exploitation mapping software. Results In Greece the dominant strain for brucellosis is Brucella melitensis. The average incidence in Greece was estimated to be 1.43/100,000. The majority of human cases were males (67.60%). The age distribution of brucellosis patients differs significantly between men and women. Brucellosis in male patients was related to high risk jobs and animal contact, while brucellosis in females was related to recent consumption of dairy products. Seasonality of the disease was different in relation to the European countries an observation attributed to the traditional customs. There was a statistically significant difference in human brucellosis incidence between the eradication and vaccination zones. Conclusion The updated information on brucellosis in Greece revealed differences in seasonality and transmission patterns. A more active cooperation between the involved public health-related sectors should be followed in order to effectively fight brucellosis as there are still foci of brucellosis in Greece.

Coxiella burnetii, the causative agent of Q fever, is an intracellular bacterial pathogen. Studies on Coxiella have shown that a type IVB secretion system (T4BSS) contributes to the establishment of the infection by transferring protein molecules. In this report, we focus on two core proteins of the Coxiella T4BSS, namely the IcmG/DotF protein (CBU_1626) and the IcmK/DotH protein (CBU_1628). Here we present a method for the recombinant expression of IcmG and IcmK in E. coli. IcmG was purified by Strep-Tactin affinity chromatography and size exclusion chromatography, while for the purification of IcmK an additional anion exchange chromatography step was introduced. The yields of the purified IcmG and IcmK proteins were 1.2 mg/L and 3 mg/L, respectively. The purified proteins showed predominant band on SDS-PAGE gel of 37 kDa for the IcmG and 40 kDa for the IcmK. Protein folding is confirmed by circular dichroism spectroscopy. The dynamic light scattering experiment indicated that IcmG and IcmK existed in a homogenous form. Further Blue native PAGE indicates the presences of a monomeric form for the IcmK and IcmG. Our work lays the basis for functional exploration and structural determination of IcmG and IcmK proteins of Coxiella's secretion system.

Objectives: Although a number of human Legionnaires' disease in tourists are recorded annually in Europe, there are few cases where a direct link can be made between the infected person and the source of infection (hotel or other accommodation). We present a scheme followed in order to track down and identify the source of infection in a tourist suffering from L. pneumophila sg 5 infection, who was accommodated in seven different hotels during his holidays in the island of Crete, and we comment on various difficulties and draw-backs of the process. Method: Water samples were collected from the seven hotels where the patient had resided and analyzed at the regional public health laboratory using cultivation and molecular tests. Results: Of 103 water samples analyzed, 19 (18.4%) were positive for Legionella non-pneumophila and 8 (7.8%) were positive for L. pneumophila. A successful L. pneumophila sg 5 match was found between the clinical and environmental sample, which led us to the final identification of the liable hotel. Conclusion: Timely notification of the case, within the the European Legionnaires' Disease Surveillance Network (ELDSNet) of the partners involved, is crucial during a course of travel associated with Legionella case investigation. Moreover, the urinary antigen test alone cannot provide sufficient information for the source identification. However, acquiring clinical as well as environmental isolates for serogroup and SBT identification is highly important for the successful matching.

Graphical abstract, Canine tick-borne pathogens such as Ehrlichia canis and Hepatozoon canis are widespread in the Mediterranean basin but have never been reported or investigated in Cyprus. We describe herein the presence of canine tick-borne pathogens in three dogs with clinical signs compatible with vector-borne diseases from Paphos area of Cyprus. Molecular and phylogenetic analysis revealed the presence of E. canis, Anaplasma platys, H. canis, Babesia vogeli and Mycoplasma haemocanis in Cyprus. One dog co-infected with E. canis, H. canis, B. vogeli and M. haemocanis is, to the best of our knowledge, the first report of this multiple co-infection in dogs. The tick-borne pathogens reported in the current study should be considered in the differential diagnoses in dogs exposed to ticks in Cyprus.

Introduction: Advancements in microbial identification occur increasingly faster as more laboratories explore, refine and extend the use of mass spectrometry in the field of microbiology.Areas covered: This review covers the latest knowledge found in the literature for quick identification of various classes of bacterial pathogens known to cause human infection by the use of MALDI-TOF MS technology. Except for identification of bacterial strains, more researchers try to ‘battle time’ in favor of the patient. These novel approaches to identify bacteria directly from clinical samples and even determine antibiotic resistance are extensively revised and discussed.Expert commentary: Mass spectrometry is the future of bacterial identification and creates a new era in modern microbiology. Its incorporation in routine practice seems to be not too far, providing a valuable alternative, especially in terms of time, to conventional techniques. If the technology further advances, quick bacterial identificatio...

Snakebite envenoming is a major health issue in many parts of the world, especially in rural areas. Vipera ammodytes is the commonest cause of snakebite in Greece. We report our experience with a patient bitten by such a snake, who developed massive intravascular hemolysis characterized by a spherocytic rather than microangiopathic hemolytic picture. This case illustrates the potential of snakebite envenoming to cause spherocytic hemolytic anemia associated with hemoglobinuria and acute renal failure, and represents the first report of V. ammodytes in this context. Another important point is that antivenom was rapidly effective in reversing spherocytic hemolytic anemia, even though several hours had elapsed since the bite.

Coxiella burnetii is the causative agent of acute and chronic Q fever in humans. Although the isolates studied so far showed a difference in virulence potential between those causing the two forms of the disease, implying a difference in their proteomic profile, the methods used so far to diagnose the two forms of the disease do not provide sufficient discriminatory capability, and human infections may be often misdiagnosed. The aim of the current study was to identify the outer membrane Com1 (CBU_1910) as a candidate protein for serodiagnostics of Q fever. The protein was cloned, expressed, purified, and used as an antigen in ELISA. The protein was then used for the screening of sera from patients suffering from chronic Q fever endocarditis, patients whose samples were negative for phase I immunoglobulin G (IgG), patients for whom at least one sample was positive for phase I IgG, and patients suffering from any kind of rheumatoid disease. Blood donors were used as the control group. Following statistical analysis, 92.4% (122/132) of the samples tested agreed with the negative clinical diagnosis, and 72.2% (26/36) agreed with the positive clinical diagnosis. Moreover, a significant correlation to the presence of the disease (p = 0.00) was calculated. The results support the idea that a Com1 antigen-based serodiagnostic test may be useful for differential diagnosis of chronic Q fever. Further studies are required to compare more immunogenic proteins of the bacterium against samples originating from patients suffering from different forms of the disease.

Vibrio harveyi is a Gram-negative, bioluminescent, marine bacterium in the genus Vibrio. It was originally described as Photobacterium fischeri [1], was later named after Beneckea harveyi [2] until it was given its final name, V. harveyi, by Baumann [3].

Hotel water systems colonized with Legionella spp. have been the source of travel-associated Legionnaires’ disease, and cases, clusters and outbreaks continue to be reported worldwide each year. A total of 132 hotels linked with travel-associated Legionnaires’ disease, as reported through the European Legionnaires’ Disease Surveillance Network, were inspected and tested for Legionella spp. during 2000–2019 by the public health authorities of the island of Crete (Greece). A total of 3311 samples were collected: 1885 (56.93%) from cold water supply systems, 1387 (41.89%) from hot water supply systems, 37 (1.12%) were swab samples and two (0.06%) were soil. Of those, 685 (20.69%), were collected from 83 (62.89%) hotels, testing positive (≥50 CFU/L) for Legionella pneumophila) serogroups 1–10, 12–14 and non-pneumophila species (L. anisa, L. erythra, L. tusconensis, L. taurinensis, L. birminghamensis, L. rubrilucens, L. londiniesis, L. oakridgensis, L. santicrusis, L. brunensis, L. maceacherii). The most frequently isolated L. pneumophila serogroups were 1 (27.92%) and 3 (17.08%). Significantly higher isolation rates were obtained from hot water supply systems (25.96%) versus cold water systems (16.98%) and swab samples (13.51%). A Relative Risk (R.R.) &gt, 1 (p &lt, 0.0001) was calculated for hot water temperature &lt, 55 °C (R.R.: 4.43), chlorine concentrations &lt, 0.2 mg/L (R.R.: 2.69), star ratings &lt, 4 (R.R.: 1.73) and absence of Water Safety Plan implementation (R.R.: 1.57).

Advancements in microbial identification occur increasingly faster as more laboratories explore, refine and extend the use of mass spectrometry in the field of microbiology. Areas covered: This review covers the latest knowledge found in the literature for quick identification of various classes of bacterial pathogens known to cause human infection by the use of MALDI-TOF MS technology. Except for identification of bacterial strains, more researchers try to 'battle time' in favor of the patient. These novel approaches to identify bacteria directly from clinical samples and even determine antibiotic resistance are extensively revised and discussed. Expert commentary: Mass spectrometry is the future of bacterial identification and creates a new era in modern microbiology. Its incorporation in routine practice seems to be not too far, providing a valuable alternative, especially in terms of time, to conventional techniques. If the technology further advances, quick bacterial identification and probable identification of common antibiotic resistance might guide patient decision-making regarding bacterial infectious diseases in the near future.

Global changes have caused a worldwide increase in reports of Vibrio-associated diseases with ecosystem-wide impacts on humans and marine animals. In Europe, higher prevalence of human infections followed regional climatic trends with outbreaks occurring during episodes of unusually warm weather. Similar patterns were also observed in Vibrio-associated diseases affecting marine organisms such as fish, bivalves, and corals. Following a possible human case of infection due to V. cholerae in the island of Kos (eastern Aegean, Greece), environmental samples were collected and tested for the presence of Vibrio species. Using chromogenic agar and MALDI-TOF MS, V. parahaemolyticus, V. vulnificus V. furnisii, V. alginolyticus, and V. fluvialis were isolated and/or identified. The presence of V. cholerae was established by PCR-sequencing analysis only. Following the susceptibility testing of the Vibrio isolates, only one, V. furnisii, showed intermediate resistance to ciprofloxacin. The rest of the isolates were susceptible to all antibiotics tested. The presence of Vibrio species in aquatic samples reveals potential dangers due to exposure to contaminated seawaters.

The current systematic review investigates the antibiotic susceptibility pattern of Legionella pneumophila isolates from the 1980s to the present day, deriving data from clinical and/or water samples from studies carried out all over the world. Eighty-nine papers meeting the inclusion criteria, i.e., “Legionella pneumophila” and “resistance to antibiotics”, were evaluated according to pre-defined validity criteria. Sixty articles referred to clinical isolates, and 18 articles reported water-related L. pneumophila isolates, while 11 articles included both clinical and water isolates. Several methods have been proposed as suitable for the determination of MICs, such as the E-test, broth and agar dilution, and disk diffusion methods, in vivo and in vitro, using various media. The E-test method proposed by the European Society of Clinical Microbiology and Infectious Diseases (EUCAST) seems to be the second most frequently used method overall, but it is the preferred method in the most recent publications (2000–2019) for the interpretation criteria. Erythromycin has been proved to be the preference for resistance testing over the years. However, in the last 19 years, the antibiotics ciprofloxacin (CIP), erythromycin (ERM), levofloxacin (LEV) and azithromycin (AZM) were the ones that saw an increase in their use. A decrease in the sensitivity to antibiotics was identified in approximately half of the reviewed articles.

Q fever is an endemic disease in different parts of Greece. The current study aimed to investigate the prevalence of acute Q fever disease in Greece through the operation of the national reference centre for Q fever. A total of 5397 sera were received from febrile patients under the suspicion of Q fever infection during a 13 years period (2001–20013). A questionnaire was filled in by the clinicians containing certain clinical/epidemiological/demographic information. The diagnosis was based both on IFA (IgG and IgM phase II antibodies against Coxiella burnetii) and on molecular means. A total of 685 (12.7 %) samples were initially tested positive for acute Q fever. The mean (±SD) age of patients was 55.3 years (±18.7). Out of the 489 convalescent samples, 134 (27.4 %) samples indicated a minimum of a four-fold seroconversion and were considered as laboratory confirmed cases of acute Q fever. Pneumonia was the most frequently encountered clinical symptom with presence in 6.8 % of all positive samples. Forty six (46) patients were laboratory confirmed as chronic Q fever cases. Climate seemed to influence the distribution of Q fever cases throughout the years. The findings of the current study comply with past studies carried out elsewhere that had demonstrated a clear relation of the disease with temperature, south winds, etc. This study represents the first large scale attempt to gather a long period information on Q fever infection in Greece. The findings of the current study support the fact that Q fever is an important endemic zoonotic disease in Greece and needs increased awareness by clinical physicians and health care system.

Colon holds a complex microbial community, which is crucial for maintaining homeostasis and regulating metabolic functions, supporting the intestinal barrier and controlling immune responses. Previous studies have supported a link between intestinal microbiota and colorectal cancer (CRC). Based on these fndings, the present review analyzed the numerous interactions that occur between microbiota and CRC, starting from the role of intestinal microbiota in colonic homoeostasis. Intestinal microbiota is a cause of CRC and involves various mechanisms such as chronic inflammation, the production of genotoxins causing DNA impairment and/or the biosynthesis of toxic compounds. Moreover, basic metabolic factors such as short-chain fatty acids (SCFAs) and bile acids are included in CRC pathogenesis. Different pathogenic pathways have been reported among different CRC regions (proximal or distal). Variations in the microbial populations are reported between the CRC from these colonic sites, possibly reflecting the bacterial dysbiosis and bioflm distribution. Bowel preparation is essential prior to colonoscopy and surgery; there is, however, minor consensus on the effects of this procedure on intestinal microbiota, notably with regard to the long-term outcomes. With regard to the therapeutic strategy in CRC, the intestinal microbiota is further involved in the modulation of the host response to chemotherapeutic agents (5-fluorouracil and irinotecan) by the interference with drug efcacy and by adverse effects and associated toxicity. In addition, the newly emerged research on CRC immunotherapy reveals an important interplay between intestinal microbiota and the immune system, which includes the possibility of targeting microbiota for the enhancement of anticancer treatment. Additional studies will further clarify the interaction between microbiota and CRC, resulting in the development of alternative therapeutic strategies by manipulating microbiota composition.

Pasteurella multocida is an important pathogen in food-producing animals and numerous virulence genes have been identified in an attempt to elucidate the pathogenesis of pasteurellosis. Currently, some of these genes including the capsule biosynthesis genes, the toxA and the OMPs-encoding genes have been suggested as epidemiological markers. However, the number of studies concerning ruminant isolates is limited, while, no attempt has ever been made to investigate the existence of ompA sequence diversity among P. multocida isolates. The aim of the present study was the comparative analysis of 144 P. multocida pneumonic isolates obtained from sheep, goats, cattle and pigs by determining the distribution of the ompA-types in conjunction with the cap-locus and toxA patterns. The ompA genotypes of the isolates were determined using both a PCR-RFLP method and DNA sequence analysis. The most prevalent capsule biosynthesis gene among the isolates was capA (86.1%); a noticeable, however, rate of capD-positive isolates (38.6%) was found among the ovine isolates that had been associated primarily with the capsule type A in the past. Moreover, an unexpectedly high percentage of toxA-positive pneumonic isolates was noticed among small ruminants (93.2% and 85.7% in sheep and goats, respectively), indicating an important epidemiological role of toxigenic P. multocida for these species. Despite their great heterogeneity, certain ompA-genotypes were associated with specific host species, showing evidence of a host preference. The OmpA-based PCR-RFLP method developed proved to be a valuable tool in typing P. multocida strains.

H Mannheìmia haemolytica αποτελεί ένα από τα σημαντικότερα αίτια πνευμονίας στα μηρυκαστικά. Εξαιτίας των σοβαρών οικονομικών επιπτώσεων που προκαλεί, διάφορες μέθοδοι έχουν χρησιμοποιηθεί με στόχο τη επιζωοτιολογική μελέτη και τη μελέτη της παθογένειας του βακτηρίου, Σκοπός της παρούσας έρευνας ήταν η διερεύνηση της συχνότητας απομόνωσης των διαφόρων οροτύπων της Mannheìmia haemolytica στην Ελλάδα και η γενετική ανάλυση ενός σημαντικού γονιδίου λοιμοτοξικότητας του βακτηρίου, του γονιδίου ompAt Για το σκοπό αυτό, μελετήθηκαν ενενήντα τέσσερα στελέχη Μ, haemolytica που απομονώθηκαν από τεμάχια πνευμονικού ιστού ενός βοοειδούς, προβάτων και αιγών με μακροσκοπικές αλλοιώσεις πνευμονίας. Η ταυτοποίηση των στελεχών έγινε με βασικές βιοχημικές δοκιμές, καθώς και με τη μέθοδο της Πολλαπλής Αλυσιδωτής Αντίδρασης της Πολυμεράσης (Multiplex PCR), 11 οροτυποποίηση των στελεχών έγινε με τη μέθοδο της έμμεσης αιμοσυγκόλλησης. Για την μελέτη των πολυμορφισμών τ ου γονιδίου ompA, χρησιμοποιήθηκαν δύο μέθοδοι: η μέθοδος της Ιΐλ^κτροφόρησης Ιΐηκτής με ΔιαβαΟμισμένη Λποδιατακτική Σύσταση (ÜGGH-Dcnaturing Gradient Gel Blectrophoresis) και η ανάλυση της αλληλουχίας του γονιδίου (DNA sequencing). Ανάμεσα στα ενενήντα τέσσερα στελέχη, βρέθηκαν οι ορύτυποι Α15 Α2, Α5, Α6, Α7, Α9 και Α12. Ο ορότυπος Α2 ήταν ο επικρατέστερος. Το μοναδικό στέλεχος που απομονώθηκαν από βοοειδές ήταν Α2, όπως και τα στελέχη από αίγες. Τα υπόλοιπα στελέχη Α2 προήλθαν από πρόβατα. Η ανάπτυξη και εφαρμογή της μεθόδου DGGE αποκάλυψε πέντε διαφορετικά πρότυπα μεταξύ των στελεχών. Τα στελέχη πρόβειας προέλευσης, εμφάνισαν μεγαλύτερη παραλλακτικότητα (τέσσερα διαφορετικά πρότυπα), από αυτά που προέρχονταν από αίγες (δύο διαφορετικά πρότυπα). Το πρότυπο 2 ήταν το πιο διαδεδομένο και ακολουθούσαν τα πρότυπα Ι και 3, Το σύνολο των στελεχών που απομονώθηκαν από αίγες ανήκε σε δύο από αυτά τα πρότυπα, Η μέθοδος της ανάλυσης των αλληλουχιών του DNA εφαρμόστηκε με στόχο την επιβεβαίωση των αποτελεσμάτων της DGGE και την εύρεση των συγκεκριμένων πολυμορφισμών. Η μελέτη του γονιδίου ompA ανέδειξε 11 διαφορετικούς γονότυπους μεταξύ των στελεχών της Μ, haemolytica, που χωρίστηκαν σε εννέα συνολικά ομάδες, Τα στελέχη των προβάτων έδειξαν μεγαλύτερη ετερογένειακαι κατατάχθηκαν σε οκτώ ομάδες, δύο από τις οποίες ήταν οι πολυπληθέστερες. Η πλειοψηφία των στελεχών που απομονώθηκαν από αίγες ανήκε στην ομάδα IX, η οποία συνέπιπτε με το πρότυπο 1 της DGGE. Η μελέτη της δευτεροταγούς δομής της πρωτεΐνης OmpA εντόπισε τις αντικαταστάσεις αμινοξέων στους επιφανειακούς βρόχους της πρωτεΐνης και, πιο συγκεκριμένα, στις υπερμεταβλητές περιοχές. Καθώς, για πρώτη φορά διεθνώς, αναφέρονται πολυμορφισμοί του γονιδίου ompA στελεχών της Μ. haemolytica τα οποία έχουν απομονωθεί από αίγες, τα στοιχεία της έρευνας συμβάλλουν στη μελέτη της εξελικτικής πορείας του γονιδίου, και στην αποσαφήνιση της ύπαρξης ή μη ειδικότητας των διαφόρων υπο-ομάδων ως προς τον ξενιστή., Pneumonia caused by Mannheìmia haemolytica is an important disease of ruminants. Because of its economic significance, several methods have been used to study the pathogenicity and epidemiology of M. haemolytica. The objectives of this study were to provide data about the prevalence of the different serotypes of the bacterium and to investigate the genetic diversity of a significant virulence factor, the ompA gene. Two methods, DNA sequencing analysis and DGGli, were used to study the polymorphisms of the ompA gene. Ninety-four isolates from pneumonic lungs were investigated. Capsular scrotyping showed that serotype Λ2 was the predominant serotype among ovine strains and the only serotype found in caprine strains. This is the first reported analysis of the ompA gene of M haemolytica strains isolated from goats. Analysis of the gene revealed five DGGli patterns and nine genotypic groups. The ovine isolates, which belonged to four DC G li patterns, showed a much greater diversity than the caprine strains, which belonged to just two DGGF patterns, Sequence analysis was used to verify the DGGE results and revealed eight genotypic groups among the ovine isolates and three among the caprine ones. Furthermore, the correlation of these results showed a great diversity of the ompA gene among serotype A2 isolates.

Rickettsia felis is a flea-transmitted pathogen however, in Greece, much work has been done on another flea-borne pathogen, R. typhi; human cases have been described and high-risk areas have been characterized. Nevertheless, little is known about human infections caused by R. felis in the country since human cases are not routinely tested for antibodies against this pathogen. During the past seven years, we have set up a protocol at the National Reference Centre in order to improve the testing of tick-borne diseases in Greece. Based on this protocol, R. conorii, R. typhi R. slovaca, R. felis, and R. mongolotimonae have been added into the routine analysis; during these last years, eight (8) cases of potential exposure to R. felis were identified by serology. On an environmental investigation carried out at the residences of the patients, the pathogen was detected in C. felis only. The demonstration of R. felis potential presence highlights the need for better testing and surveillance of the pathogen.

In Greece standard tests are performed in the watering and cooling systems of hotels’ units either as part of the surveillance scheme or following human infection. The purpose of this study was to establish the minimum inhibitory concentration (MIC) distributions of environmental Legionella isolates for six antimicrobials commonly used for the treatment of Legionella infections, by MIC-test methodology. Water samples were collected from 2004 to 2011 from 124 hotels from the four prefectures of Crete (Greece). Sixty-eight (68) Legionella isolates, comprising L. pneumophila serogroups 1, 2, 3, 5, 6, 8, 12, 13, 15, L. anisa, L. rubrilucens, L. maceachernii, L. quinlivanii, L. oakridgensis, and L. taurinensis, were included in the study. MIC-tests were performed on buffered charcoal yeast extract with α-ketoglutarate, L-cysteine, and ferric pyrophosphate. The MICs were read after 2 days of incubation at 36 ± 1 °C at 2.5% CO2. A large distribution in MICs was recorded for each species and each antibiotic tested. Rifampicin proved to be the most potent antibiotic regardless of the Legionella spp.; tetracycline appeared to have the least activity on our environmental isolates. The MIC-test approach is an easy, although not so cost-effective, way to determine MICs in Legionella spp. These data should be kept in mind especially since these Legionella species may cause human disease.

Although tick-borne rickettsiosis is endemic in Greece, until recently, human samples arriving at the National Reference Centre under suspicion of rickettsial infection were routinely tested only for Rickettsia typhi and R. conorii. However, identification of additional rickettsia species in ticks prompted revision of the protocol in 2010. Until that year, all human samples received by the laboratory were tested for antibodies against R. conorii and R. typhi only. Now, tests for R. slovaca, R. felis, and R. mongolotimonae are all included in routine analysis. The current description of a human R. slovaca case is possible as a result of these changes in routine testing.

Tick-borne rickettsioses are endemic in Greece; however, until recently, only Rickettsia typhi and R. conorii were tested routinely in human samples arriving at the National Reference Center. During the last few years, the identification of different rickettsia species in ticks led to the introduction of other spotted fever group rickettsiae in routine analysis. Under the new scheme, R. massiliae is now tested routinely in human samples; herein, we describe a human case of this infection.