CTX-M-15 Type Extended-Spectrum Beta-Lactamase-Producing Enterobacter cloacae In Bioaerosol of a Municipal Solid Waste Recycling Plant: A New Possible Reservoir of Infection?

Background: Although there are many reports of antibiotic resistant microorganisms released from the treated municipal wastewater, less attention has been given to other waste treatment activities. We report the occurrence of antibiotic resistant strains isolated from the working setting of a solid waste recycling plant in Italy which serves 195 municipalities. Methods: To assess microbial contamination levels, several sampling points were chosen for their relevance in evaluating exposure of the workers to biological risk, especially during indoor operations. Active sampling was carried out using the Surface Air System and Rodac plate method was applied to surface sampling. Species identification and antimicrobial susceptibilities were obtained by Vitek2 System (bioMérieux, France) and by the agar-diffusion method. The presence of resistance genes was investigated by multiplex PCR assay. Results: In all sampling points a significant contamination of aerosol was detected, although the total microbial counts resulted within the limit proposed by the National authority (10000 CFU/sqm). The counts of Enterobacteriaceae were always above the limit of 100 CFU/sqm and strains of Enterobacter cloacae resistant to third generation cephalosporins were detected, carrying the blaCTX-M15 gene. Conclusions: The contamination of workplace with multidrug-resistant strains is a crucial area for public health actions to avoid the conjunction of factors that promote evolution and spread of antibiotic resistance

ChatGPT and the rise of large language models: the new AI-driven infodemic threat in public health

: Large Language Models (LLMs) have recently gathered attention with the release of ChatGPT, a user-centered chatbot released by OpenAI. In this perspective article, we retrace the evolution of LLMs to understand the revolution brought by ChatGPT in the artificial intelligence (AI) field. The opportunities offered by LLMs in supporting scientific research are multiple and various models have already been tested in Natural Language Processing (NLP) tasks in this domain. The impact of ChatGPT has been huge for the general public and the research community, with many authors using the chatbot to write part of their articles and some papers even listing ChatGPT as an author. Alarming ethical and practical challenges emerge from the use of LLMs, particularly in the medical field for the potential impact on public health. Infodemic is a trending topic in public health and the ability of LLMs to rapidly produce vast amounts of text could leverage misinformation spread at an unprecedented scale, this could create an "AI-driven infodemic," a novel public health threat. Policies to contrast this phenomenon need to be rapidly elaborated, the inability to accurately detect artificial-intelligence-produced text is an unresolved issue

Biofilm growth on orthopedic implantable materials: static or dynamic condition what is the most appropriate methodological tools to study device-related infections?

Aim Study of biofilm growth under static and dynamic conditions to evaluate the most suitable orthopedic materials on the prevention of device-related infections. Method Biofilms of Staphylococcus epidermidis (ATCC 35984) icaA and icaD genes positive and Pseudomonas aeruginosa (DSM 939) were generated under static and dynamic conditions, adding the bacterial inocula on titanium, carbon, polycarbonate and carbon-peek coupons housed in flat bottom test tubes or in the CDC Biofilm Reactor (CBR) system respectively. Biofilm growth was evaluated by MTT assay after 48 hours. Results Results of dynamic model showed a better capacity of S.epidermidis to grow with a rotation between 120-60 rpm on each tested materials (Mann-Whitney test, p-value < 0,05) than P.aeruginosa. Titanium was thematerial on which the bacterial strains adhered less, whereas carbon and polycarbonate allowed greatest adherence of P.aeruginosa (Mann-Whitney test, p-value < 0,05). Results of static model showed that both species grew on each materials without distinction (Kruskal-Wallis test, p-value 0,95). S.epidermidis growth was better also under static condition. Conclusions the static model was not able to evaluate the different adhesion capacity of the strains to the materials, confirming the dynamic model is the most suitable tool for the study of orthopedic materials on the prevention of device-related infections. This research was funded by the University of Pisa, PRA 2017_18 Projec

Presence of Legionella spp. in Hot Water Networks of Different Italian Residential Buildings: A Three-Year Survey

Although the European reports highlight an increase in community-acquired Legionnaires' disease cases, the risk of Legionella spp. in private houses is underestimated. In Pisa (Italy) we performed a three-year survey on Legionella presence in 121 buildings with an independent hot water production (IB); 64 buildings with a central hot water production (CB); and 35 buildings with a solar thermal system for hot water production (TB). From all the 220 buildings Legionella spp. was researched in two hot water samples collected either at the recirculation point or on the first floor and on the last floor, while the potable water quality was analysed in three cold water samples collected at the inlet from the aqueduct network, at the exit from the autoclave, and at the most remote tap. Legionella pneumophila sg1, Legionella pneumophila sg2-16, and non-pneumophila Legionella species were detected in 26% of the hot water networks, mostly in CB and TB. In these buildings we detected correlations between the presence of Legionella and the total chlorine concentration decrease and/or the increase of the temperature. Cold water resulted free from microbiological hazards, with the exception of Serratia liquefaciens and Enterobacter cloacae isolated at the exit from two different autoclaves. We observed an increase in total microbial counts at 22 °C and 37 °C between the samples collected at the most remote taps compared to the ones collected at the inlet from the aqueduct. The study highlights a condition of potential risk for susceptible categories of population and supports the need for measures of risk assessment and control

Evaluation of Legionella pneumophila Decrease in Hot Water Network of Four Hospital Buildings after Installation of Electron Time Flow Taps

Legionella spp. control is a critical issue in hospital with old water networks. Chemical disinfection methods are applied as a control measure over prolonged time periods, but Legionella may be resistant to chemical agents in pipeworks with low flow and frequent water stagnation. We evaluated Legionella spp. colonization in the hot water network of Italian hospitals after the installation of time flow taps (TFTs). In the period between 2017 and 2019, TFTs were installed in four hospital water networks. They were programmed in order to obtain a hot water flow of 192 L/day from each TFTs. A continuous chlorination system (chlorine dioxide) and a cold water pre-filtration device were applied in all the buildings. Before and after TFT installation, Legionella spp. was investigated at scheduled times. Before TFT installation, Legionella pneumophila was detected in all the hospitals with counts ranging from 2 × 102 to 1.4 × 105 CFU/L. After TFT installation, a loss in Legionella pneumophila culturability was always achieved in the period between 24 h and 15 days. Total chlorine concentration (Cl2) was detected in the range between 0.23 and 0.36 mg/L while temperature values were from 44.8 to 53.2 °C. TFTs together with chemical disinfection represent a method which improve water quality and disinfectant efficacy, reducing Legionella colonization in dead-end sections

Epidemiology of MRSA and current strategies in Europe and Japan

The prevalence of health-care associated infections caused by multi-drug resistant organisms has significantly increased over the past decade. Among these organisms, Methicillin-resistant Staphylococcus aureus (MRSA) plays a prominent and increasing role. Because of consequences for patients and the economic burden in course of prolonged treatment following MRSA infections and additional indirect costs for e.g. isolation or antiseptic treatment, this trend will further damage European health-care systems

Colonization by Legionella spp. of water networks in residential buildings of the Province of Pisa, Italy

Despite the increase of community acquired cases of legionellosis in Italy over the last years, the Italian guidelines do not give indications for prevention and control of Legionella in the hot water networks (or centralized conditioning systems) of residential buildings. We performed a survey on eight medium sized apartment buildings in the Pisa district to assess the prevalence of Legionella spp. in the water network and the respondance to drinking water requisites at the point of use, according to the Italian norms

Evaluation of a modified cleaning procedure in the prevention of carbapenem-resistant Acinetobacter baumannii clonal spread in a burn intensive care unit using a high-sensitivity luminometer

Background: Enhanced environmental cleaning practices are among the most accepted measures for controlling the spread of carbapenem-resistant . Acinetobacter baumannii (CR-Ab). Aim: To evaluate the impact of heightened cleaning on an ongoing CR-Ab outbreak in a burn intensive care unit (BICU) of an Italian teaching hospital, where chlorhexidine-60% isopropyl alcohol was applied as a complementary disinfectant on high-touch surfaces. Methods: Compliance with the microbial limit proposed for the BICU by AFNOR-NF-S90-351 (20 colony-forming units/100cm2) was assessed by plate count, and compared with the results obtained with intracellular adenosine triphosphate (ATP) detection. Genotyping was performed using pulsed-field gel electrophoresis. Findings: During the standard cleaning regimen, three out of 23 samples (13%) gave results over the AFNOR limit and five (21.7%) showed unacceptable ATP levels with 100 relative light units/100cm2 as the benchmark limit (sensibility 86.4%, specificity 92.2%). Following improvement of the cleaning procedure, only two samples out of 50 (4%) did not satisfy the microbiological criteria and seven (14%) exceeded the ATP limit. In a successive phase, eight of 30 samples collected showed unacceptable results (27%). Conclusions: Adding chlorhexidine-60% isopropyl alcohol as complementary disinfectant proved to be effective for reducing environmental microbial contamination, ATP levels and CR-Ab infection/colonization in patients admitted to the BICU. Real-time monitoring by ATP assay was useful for managing the cleaning schedule and reducing hospital infections, although the calculated values must be interpreted as cleanliness indicators rather than risk indicators

The Italian national surgical site infection surveillance programme and its positive impact, 2009 to 2011

Programmes surveying surgical site infection (SSI) have been implemented throughout the world and are associated with a reduction in SSI rates. We report data on non-prosthetic surgery from the Italian SSI surveillance programme for the period 2009 to 2011. Participation in the programme was voluntary. We evaluated the occurrence of SSI, based on protocols from the European Centre for Disease Prevention and Control, within 30 days of surgery. Demographic data, risk factors, type of surgery and presence of SSI were recorded. The National Coordinating Centre analysed the pooled data. On 355 surgical wards 60,460 operations were recorded, with the number of surveyed intervention doubling over the study period. SSI was observed in 1,628 cases (2,6%) and 60% of SSI were diagnosed through 30-days post discharge surveillance. Operations performed in hospitals with at least two years of surveillance showed a 29% lower risk of SSI. Longer intervention duration, American Society of Anesthesiologists’ (ASA) score of at least three, and pre-surgery hospital stay of at least two days were associated with increased risk of SSI, while videoscopic procedures had reduced SSI rates. Implementation of a national surveillance programme was helpful in reducing SSI rates and should be prioritised in all healthcare systems