A Practical Method for Mapping of Pesticide Loss Risk in Cultivated Soils of Greece

In an attempt to map the soil factors controlling pesticide losses, surface soil samples were collected from 196 sites in the cultivated area of Trifyllia, SW Peloponnese, Greece. Up to now, the pesticide losses risk in the studied area is unknown. For this aim, the following key characteristics that affect movement or binding have been taken into consideration: soil texture, slope and soil organic matter content. A GIS map was compiled from discrete soil variables that affect pesticide losses (leaching and/or runoff). According to soil texture, 3 moderate leaching risk classes, 2 high and 1 low were defined, and the respective classes based on Soil Organic Matter (SOM) content were 3 low risk classes, 2 moderate and 1 class of high risk. The study area consists of two soil slope classes 0-2% and 2-6% which were used to calculate the leaching potential of pesticides. The compiled maps can be used by local authorities in order to minimize the potential negative environmental impacts of pesticide usage at farm level, and to suggest various mitigation strategies. Appropriate farming practices must be applied to decrease leaching or losses by runoff in order to mitigate the pollution of shallow aquifers and surface waters in SW Peloponnese. Rational irrigation management is of high importance as it increases the pesticide effectiveness and reduces off site movement. Moreover, runoff of pesticides can be reduced by using minimum tillage techniques to mitigate soil erosion. Finally, farming systems and practices that increase soil organic matter content (e.g. no tillage) can reduce substantially the risk of water pollution by pesticides

Effects of irrigation and green manure on corn (Zea mays l.) biomass and grain yield

The effect of green manure on the growth of irrigated corn (Zea mays L. cv Cisko) was investigated under different drip irrigation rates on a clay soil in Greece. A feed pea (Pisum sativum L. cv Olympus) crop was established in autumn and incorporated into the soil in spring, about 3 weeks before the sowing of the subsequent corn. During the growing period, the growth stages and yield of corn were assessed under three drip irrigation levels I1 (33% low), I2 (66% moderate) and I3 (100% full of actual evapotranspiration, ETm) and two cultivation practices a) application of green manure and b) experiment without previous green manuring. The positive effects of green manuring were greater in the moderately and fully irrigated plots. Drip irrigation was applied to minimize nitrate leaching which requires low volume of water. In plots receiving moderate or full irrigation, biomass, leaf area index (LAI) and seed yield were much higher in comparison to stressed plants (33% ETm). Increased yield and dry biomass obtained in the plots after incorporation of feed pea residues, may be attributed mainly to the elevated amount of soil organic matter (SOM). The increased yield exceeds the overall cost for green manure application, and this economic incentive is expected to be even more significant taking into account the continuous improvement of soil conditions. © 2018, Sociedad Chilena de la Ciencia del Suelo. All rights reserved

Green Manuring for Low-input Irrigated Maize Cultivation as an Energy Crop in Mediterranean Climates

Introduction of high input crops to existing rotation schemes for bio-energy production such as corn in Mediterranean areas would only be possible by improving its yield and decreasing the cultivation costs. This work focusses on the combined effect of irrigation rate and green manuring on growth and productivity of irrigated corn grown in typical Mediterranean lowland. On a flat, calcareous clay-loam soil, a three-year field experiment was conducted. Pisum sativum was sown in specific plots every year in November and grew as cover crop under rainfed conditions until mid-April where its biomass was incorporated into the soil, while maize was sown by the end of April. A 3 × 2 factorial split-plot design was used in 3 blocks. Corn irrigation comprised the main plots and pea incorporation comprised the sub-plots. Soil moisture was monitored at weakly intervals at 10 layers of 10 cm each down to 1 m soil depth. Corn growth and final yield were monitored by means of distracting samplings. The overall conclusion is the significant positive effect of green manuring on corn biomass and seed yield. This effect was mainly attributed to greater water use efficiency as green manuring was associated with greater moisture content within the rooting zone compared to control plots. The increased yield obtained could offset the increased costs of growing pea as green manure (increase in farmers’ income of 20–110 € ha−1), allowing green manuring to become more widely used to reduce fertilization and irrigation inputs while also allowing corn to be introduced into current crop rotations for bio-energy production. © 2021, Springer Nature Switzerland AG

Forecasting models of infections due to carbapenem-resistant Gram-negative bacteria in an intensive care unit in an endemic area

Objectives: The aim of this study was to forecast the monthly incidence rates of infections [infections/1000 bed-days (IBD)] due to carbapenem-resistant Klebsiella pneumoniae (CRKP), carbapenem-resistant Pseudomonas aeruginosa (CRPA), carbapenem-resistant Acinetobacter baumannii (CRAB) and total carbapenem-resistant Gram-negative bacteria (CRGNB) in an endemic intensive care unit (ICU) during the subsequent year (December 2016–December 2017) following the observational period. Methods: A 52-month observational period (August 2012–November 2016) was used. Two forecasting models, including a simple seasonal model for CRGNB, CRKP and CRPA and Winters’ additive model for CRAB infections, were applied. Results: The models predicted the highest infection rates for CRKP, CRAB and CRGNB in January and September 2017 (23.8/23.4, 24.6/28.5 and 46.8/46.7 IBD, respectively) and for CRPA in February and March 2017 (8.3 and 7.9, respectively). The highest observed rates for CRKP, CRAB and CRGNB were indeed in January and September 2017 (25.6/19.0, 34.2/23.8 and 59.8/42.8 IBD, respectively); and for CRPA in February and March of the same year (15.2 and 12.7, respectively). The increased rates may be associated with personnel's annual work programme and behavioural factors. Conclusion: Forecasting models in endemic ICUs may assist in implementation strategies for infection control measures. © 2019 International Society for Antimicrobial Chemotherap

Effects of an Active Surveillance Program and Enhanced Infection Control Measures on Carbapenem-Resistant Gram-Negative Bacterial Carriage and Infections in Pediatric Intensive Care

We evaluated the effects of enhanced infection control measures (ICMs) on carriage and infections of carbapenem-resistant Gram-negative bacteria (CRGNB) in a pediatric intensive care unit. We conducted a quasi-experimental study, including patients with infections of CRGNB retrospectively for 13 months and those participating in an active surveillance program prospectively for 22 months. Active surveillance (weekly rectal swabs) was implemented during a 63-week subperiod with standard ICMs and a subsequent 27-week subperiod with enhanced ICMs (intensified ICMs supplemented with audits and feedback). Prevalence, colonization pressure, incidence, and infections of CRGNB and compliance with ICMs and enhanced ICMs were recorded. Evaluation of results was performed using time series (TS) and interrupted TS. Compliance with hand hygiene improved during the second subperiod of active surveillance compared with the first; prevalence, colonization pressure, and incidence of CRGNB decreased significantly. The linear trend of centered moving average for carbapenem-resistant Klebsiella pneumoniae (CRKP) decreased from 1.2 to 0.1 infections/1,000 bed-days (IBD) (p = 0.046), while it remained unchanged for carbapenem-resistant Acinetobacter baumannii (CRAB) and increased for carbapenem-resistant Pseudomonas aeruginosa (CRPA) from 0.0 to 2.1 IBD (p < 0.001). Enhanced ICMs can reduce CRKP infections in endemic units, in contrast to CRPA and CRAB infections, which are more difficult to eradicate. © Copyright 2019, Mary Ann Liebert, Inc

Impact of active surveillance and infection control measures on carbapenem-resistant Gram-negative bacterial colonization and infections in intensive care

Background: Carbapenem-resistant Gram-negative bacteria (CRGNB) infections constitute a global threat for critically ill patients and the outcome of their hospitalization. Early identification of CRGNB through rectal surveillance cultures and routine infection control measures including contact precautions, use of appropriate disinfectants, staff education on cleaning, and hand hygiene may reduce the dissemination of CRGNB. Aim: To assess the impact of enhanced infection control measures on CRGNB infections in a nine-bed polyvalent intensive care unit in a tertiary level hospital in an endemic area. Methods: A quasi-experimental study, which included patients with CRGNB infection retrospectively for six months and those participating in an active surveillance programme prospectively for the subsequent 22 months. Active surveillance programme (weekly rectal swabs) was implemented including two sub-periods with infection control measures and enhanced infection control measures. CRGNB incidence, prevalence, colonization pressure, infections and compliance with infection control measures and enhanced infection control measures were recorded. Analysis was performed through time-series and interrupted time-series. Findings: During the active surveillance programme, enhanced infection control measures led to a steeper downwards trend in incidence, prevalence, and colonization pressure for CRGNB compared to the infection control measures sub-period. The linear trend was for carbapenem-resistant Klebsiella pneumoniae (CRKP) and Pseudomonas aeruginosa (CRPA) infections to decrease from 19.6 to 8.1 infections per 1000 bed-days (IBD) (P = 0.001) and from 5.1 to 1.79 IBD (P = 0.043), respectively. By contrast, carbapenem-resistant Acinetobacter baumannii infections increased from 5.2 to 15.3 IBD (P = 0.001). Conclusion: Enhanced infection control measures including enhanced hand hygiene, active surveillance combined with contact precautions, education, audits and feedback policies and interventions could reduce CRKP and CRPA in endemic areas. © 2018 The Healthcare Infection Societ

Epidemiological surveillance of multidrug-resistant gram-negative bacteria in a solid organ transplantation department

Background: We assessed the impact of intensified infection control measures (ICM) on colonization and infection caused by carbapenem-resistant (CR) Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii in a solid organ transplantation (SOT) department. Methods: A quasi-experimental methodology was followed. The study was divided into three periods: pre-intervention, intervention with implementation of an ICM bundle including active surveillance program (ASP) and gradually enhanced measures, and post-ASP without ASP. The bundle included active surveillance cultures, contact precautions, hand hygiene, education of health care workers (HCWs), monitoring of compliance, and environmental cleaning. Incidence of colonization and infection caused by CR gram-negative bacteria was recorded. Molecular analysis of CR bacteria was performed for a certain period. Results: During the intervention, incidence of colonization reduced from 19% to 9% (P<.001). The compliance of HCWs with contact precautions and hand hygiene also improved. Monthly incidence of infections caused by these CR bacteria increased from 2.8 to 6.9/1000 bed-days (P<.001). However, this increase did not have such a strong trend after the intervention. Most K. pneumoniae isolates, the commonest pathogen, carried the blaKPC gene. Colonization and infection rates by CR K. pneumoniae, P. aeruginosa, and A. baumannii were high among SOT recipients. Conclusion: In settings where CR gram-negative bacteria are endemic, colonization and infection rates by these bacteria are high among SOT recipients. Implementation of enhanced ICM in all related units of a hospital, although challenging, reduces colonization rates by CR gram-negative bacteria. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Lt

Cluster-distinguishing genotypic and phenotypic diversity of carbapenem-resistant gram-negative bacteria in solid-organ transplantation patients: A comparative study

Purpose. Solid-organ transplant recipients may display high rates of colonization and/or infection by multidrug-resistant bacteria. We analysed and compared the phenotypic and genotypic diversity of carbapenem-resistant (CR) strains of Klebsiella pneumoniae, Pseudomonas aeruginosa and Acinetobacter baumannii isolated from patients in the Solid Organ Transplantation department of our hospital. Methodology. Between March 2012 and August 2013, 56 CR strains from various biological fluids underwent antimicrobial susceptibility testing with VITEK 2, molecular analysis by PCR amplification and genotypic analysis with pulsed-field gel electrophoresis (PFGE). They were clustered according to antimicrobial drug susceptibility and genotypic profiles. Diversity analyses were performed by calculating Simpson’s diversity index and applying computed rarefaction curves. Results/Key findings. Among K. pneumoniae, KP-producers predominated (57.1%). VIM and OXA-23 carbapenemases prevailed among P. aeruginosa and A. baumannii (89.4 and 88.9%, respectively). KPC-producing K. pneumoniae and OXA-23 A. baumannii were assigned in single PFGE pulsotypes. VIM-producing P. aeruginosa generated multiple pulsotypes. CR K. pneumoniae strains displayed phenotypic diversity in tigecycline, colistin (CS), amikacin (AMK), gentamicin (GEN) and cotrimoxazole (SXT) (16 clusters); P. aeruginosa displayed phenotypic diversity in cefepime (FEP), ceftazidime, aztreonam, piperacillin, piperacillin–tazobactam, AMK, GEN and CS (9 clusters); and A. baumannii displayed phenotypic diversity in AMK, GEN, SXT, FEP, tobramycin and rifampicin (8 clusters). The Simpson diversity indices for the interpretative phenotype and PFGE analysis were 0.89 and 0.6, respectively, for K. pneumoniae strains (P < 0.001); 0.77 and 0.6 for P. aeruginosa (P=0.22); and 0.86 and 0.19 for A. baumannii (P=0.004). Conclusion. The presence of different antimicrobial susceptibility profiles does not preclude the possibility that two CR K. Pneumoniae or A. baumannii isolates are clonally related. © 2017 The Authors

Molecular epidemiology of endemic carbapenem-resistant gram-negative bacteria in an intensive care unit

The molecular epidemiology of endemic carbapenem-resistant Klebsiella pneumoniae (CRKP), carbapenem-resistant Pseudomonas aeruginosa (CRPA), and carbapenem-resistant Acinetobacter baumannii (CRAB) in an intensive care unit located in an endemic area with high rates of resistance was investigated. A CRPA strain producing VIM and KPC concurrently was detected for the first time in an endemic area. CRKP strains producing K. pneumoniae carbapenemase predominated and were mainly assigned to the "hyperepidemic Greek clone." Predominant OXA-23-like producing CRAB strains were assigned to multiple pulsotypes. © 2019 Mary Ann Liebert, Inc., publishers

Cluster-distinguishing genotypic and phenotypic diversity of carbapenem-resistant gram-negative bacteria in solid-organ transplantation patients: A comparative study

Purpose. Solid-organ transplant recipients may display high rates of colonization and/or infection by multidrug-resistant bacteria. We analysed and compared the phenotypic and genotypic diversity of carbapenem-resistant (CR) strains of Klebsiella pneumoniae, Pseudomonas aeruginosa and Acinetobacter baumannii isolated from patients in the Solid Organ Transplantation department of our hospital. Methodology. Between March 2012 and August 2013, 56 CR strains from various biological fluids underwent antimicrobial susceptibility testing with VITEK 2, molecular analysis by PCR amplification and genotypic analysis with pulsed-field gel electrophoresis (PFGE). They were clustered according to antimicrobial drug susceptibility and genotypic profiles. Diversity analyses were performed by calculating Simpson’s diversity index and applying computed rarefaction curves. Results/Key findings. Among K. pneumoniae, KP-producers predominated (57.1%). VIM and OXA-23 carbapenemases prevailed among P. aeruginosa and A. baumannii (89.4 and 88.9%, respectively). KPC-producing K. pneumoniae and OXA-23 A. baumannii were assigned in single PFGE pulsotypes. VIM-producing P. aeruginosa generated multiple pulsotypes. CR K. pneumoniae strains displayed phenotypic diversity in tigecycline, colistin (CS), amikacin (AMK), gentamicin (GEN) and cotrimoxazole (SXT) (16 clusters); P. aeruginosa displayed phenotypic diversity in cefepime (FEP), ceftazidime, aztreonam, piperacillin, piperacillin–tazobactam, AMK, GEN and CS (9 clusters); and A. baumannii displayed phenotypic diversity in AMK, GEN, SXT, FEP, tobramycin and rifampicin (8 clusters). The Simpson diversity indices for the interpretative phenotype and PFGE analysis were 0.89 and 0.6, respectively, for K. pneumoniae strains (P < 0.001); 0.77 and 0.6 for P. aeruginosa (P=0.22); and 0.86 and 0.19 for A. baumannii (P=0.004). Conclusion. The presence of different antimicrobial susceptibility profiles does not preclude the possibility that two CR K. Pneumoniae or A. baumannii isolates are clonally related. © 2017 The Authors