Characterization of the Pathogenic Potential of the Beach Sand Microbiome and Assessment of Quicklime as a Remediation Tool.

Beach sand may act as a reservoir for potential human pathogens, posing a public health risk. Despite this, the microbiological monitoring of sand microbiome is rarely performed to determine beach quality. In this study, the sand microbial population of a Northern Adriatic Sea beach sand was profiled by microbiological (CFU counts) and molecular methods (WGS, microarray), showing significant presence of potential human pathogens including drug-resistant strains. Consistent with these results, the potential of quicklime as a restoring method was tested in vitro and on-field. Collected data showed that adding 1-3% quicklime (w/w) to sand provided an up to -99% of bacteria, fungi, and viruses, in a dose- and time-dependent manner, till 45 days post-treatment. In conclusion, data suggest that accurate monitoring of sand microbiome may be essential, besides water, to assess beach quality and safety. Moreover, first evidences of quicklime potential for sand decontamination are provided, suggesting its usage as a possible way to restore the microbiological quality of sand in highly contaminated areas.

Potential Use of a Combined Bacteriophage-Probiotic Sanitation System to Control Microbial Contamination and AMR in Healthcare Settings: A Pre-Post Intervention Study.

Microbial contamination in the hospital environment is a major concern for public health, since it significantly contributes to the onset of healthcare-associated infections (HAIs), which are further complicated by the alarming level of antimicrobial resistance (AMR) of HAI-associated pathogens. Chemical disinfection to control bioburden has a temporary effect and can favor the selection of resistant pathogens, as observed during the COVID-19 pandemic. Instead, probiotic-based sanitation (probiotic cleaning hygiene system, PCHS) was reported to stably abate pathogens, AMR, and HAIs. PCHS action is not rapid nor specific, being based on competitive exclusion, but the addition of lytic bacteriophages that quickly and specifically kill selected bacteria was shown to improve PCHS effectiveness. This study aimed to investigate the effect of such combined probiotic-phage sanitation (PCHSφ) in two Italian hospitals, targeting staphylococcal contamination. The results showed that PCHSφ could provide a significantly higher removal of staphylococci, including resistant strains, compared with disinfectants (-76%, p < 0.05) and PCHS alone (-50%, p < 0.05). Extraordinary sporadic chlorine disinfection appeared compatible with PCHSφ, while frequent routine chlorine usage inactivated the probiotic/phage components, preventing PCHSφ action. The collected data highlight the potential of a biological sanitation for better control of the infectious risk in healthcare facilities, without worsening pollution and AMR concerns.

Shaping the subway microbiome through probiotic-based sanitation during the COVID-19 emergency: a pre-post case-control study.

BACKGROUND: The COVID-19 pandemic has highlighted the extent to which the public transportation environment, such as in subways, may be important for the transmission of potential pathogenic microbes among humans, with the possibility of rapidly impacting large numbers of people. For these reasons, sanitation procedures, including massive use of chemical disinfection, were mandatorily introduced during the emergency and remain in place. However, most chemical disinfectants have temporary action and a high environmental impact, potentially enhancing antimicrobial resistance (AMR) of the treated microbes. By contrast, a biological and eco-sustainable probiotic-based sanitation (PBS) procedure was recently shown to stably shape the microbiome of treated environments, providing effective and long-term control of pathogens and AMR spread in addition to activity against SARS-CoV-2, the causative agent of COVID-19. Our study aims to assess the applicability and impact of PBS compared with chemical disinfectants based on their effects on the surface microbiome of a subway environment. RESULTS: The train microbiome was characterized by both culture-based and culture-independent molecular methods, including 16S rRNA NGS and real-time qPCR microarray, for profiling the train bacteriome and its resistome and to identify and quantify specific human pathogens. SARS-CoV-2 presence was also assessed in parallel using digital droplet PCR. The results showed a clear and significant decrease in bacterial and fungal pathogens (p < 0.001) as well as of SARS-CoV-2 presence (p < 0.01), in the PBS-treated train compared with the chemically disinfected control train. In addition, NGS profiling evidenced diverse clusters in the population of air vs. surface while demonstrating the specific action of PBS against pathogens rather than the entire train bacteriome. CONCLUSIONS: The data presented here provide the first direct assessment of the impact of different sanitation procedures on the subway microbiome, allowing a better understanding of its composition and dynamics and showing that a biological sanitation approach may be highly effective in counteracting pathogens and AMR spread in our increasingly urbanized and interconnected environment. Video Abstract.

Introduction of Probiotic-Based Sanitation in the Emergency Ward of a Children's Hospital During the COVID-19 Pandemic.

Background: Antimicrobial resistance (AMR) represents a major threat to public health, especially in the hospital environment, and the massive use of disinfectants to prevent COVID-19 transmission might intensify this risk, possibly leading to future AMR pandemics. However, the control of microbial contamination is crucial in hospitals, since hospital microbiomes can cause healthcare-associated infections (HAIs), which are particularly frequent and severe in pediatric wards due to children having high susceptibility. Aim: We have previously reported that probiotic-based sanitation (PCHS) could stably decrease pathogens and their AMR in the hospital environment, reduce associated HAIs in adult hospitals, and inactivate enveloped viruses. Here, we aimed to test the effect of PCHS in the emergency room (ER) of a children's hospital during the COVID-19 pandemic. Methods: Conventional chemical disinfection was replaced by PCHS for 2 months during routine ER sanitation; the level of environmental bioburden was characterized before and at 2, 4, and 9 weeks after the introduction of PCHS. Microbial contamination was monitored simultaneously by conventional culture-based CFU count and molecular assays, including 16S rRNA NGS for bacteriome characterization and microarrays for the assessment of the resistome of the contaminating population. The presence of SARS-CoV-2 was also monitored by PCR. Results and conclusions: PCHS usage was associated with a stable 80% decrease in surface pathogens compared to levels detected for chemical disinfection (P < 0.01), accompanied by an up to 2 log decrease in resistance genes (Pc < 0.01). The effects were reversed when reintroducing chemical disinfection, which counteracted the action of the PCHS. SARS-CoV-2 was not detectable in both the pre-PCHS and PCHS periods. As the control of microbial contamination is a major issue, especially during pandemic emergencies, collected data suggest that PCHS may be successfully used to control virus spread without simultaneous worsening of the AMR concern.

An Innovative Strategy for the Effective Reduction of MDR Pathogens from the Nosocomial Environment.

Antimicrobial resistance (AMR) is currently one of the main concerns for human health.Due to its rapid increase and global diffusion, several common microbial infections might become not curable in the future decades, making it impossible to apply other lifesaver therapies, such as transplant or chemotherapy.AMR is frequently observed in hospital pathogens, due to selective pressure exerted by antibiotic use, and consistently with this, in the recent years, many actions have been proposed to limit AMR spread, including hygiene measures for hospital professionals and a wiser antibiotic usage.Indeed, the hospital environment itself represents a reservoir of pathogens, whose control was so far addressed by conventional sanitation procedures, which however cannot prevent recontamination and might further favour the selection of resistant strains.Here we report the results collected by studying an innovative sanitation strategy based on the use of probiotic bacteria, capable of reducing in a stable way the surface load of pathogens and their AMR. Collected data suggest that this system might contribute significantly to AMR control and might be thus considered as one of the tools for AMR and infection prevention and control.

Effective elimination of Staphylococcal contamination from hospital surfaces by a bacteriophage-probiotic sanitation strategy: a monocentric study.

Persistent contamination of hospital surfaces and antimicrobial resistance (AMR) is recognized as major causes of healthcare-associated infections (HAI). We recently showed that probiotic-based sanitation (PCHS) can stably decrease surface pathogens and reduce AMR and HAIs. However, PCHS action is slow and non-specific. By contrast, bacteriophages have been proposed as a decontamination method as they can rapidly attack specific targets, but their routine application has never been tested. Here, we analysed the feasibility and effectiveness of phage addition to PCHS sanitation, aiming to obtain a rapid and stable abatement of specific pathogens in the hospital environment. Staphylococcal contamination in the bathrooms of General Medicine wards was analysed, being those areas the most contaminated and Staphylococci the most prevalent bacteria in such settings. Results showed that a daily phage application by nebulization induced a rapid and significant decrease in Staphylococcus spp. load on treated surfaces, up to 97% more than PCHS alone (P < 0.001), suggesting that such a system might be considered as a part of prevention and control strategies, to counteract outbreaks of specific pathogens and prevent associated infections.

Impact of a probiotic-based hospital sanitation on antimicrobial resistance and HAI-associated antimicrobial consumption and costs: a multicenter study.

PURPOSE: Antimicrobial resistance (AMR) is one of the major threats to human health, and the high frequency of resistant pathogens in the hospital environment can contribute to the transmission of difficult-to-treat health care-associated infections (HAIs). We recently reported that, compared with conventional chemical cleaning, the use of a microbial-based sanitation strategy (Probiotic Cleaning Hygiene System [PCHS]) was associated with remodulation of hospital microbiota and reduction of HAI incidence. Here, we aimed to analyze the impact of PCHS on AMR and related effects, such as HAI-associated antimicrobial drug consumption and costs. PATIENTS AND METHODS: Five Italian hospitals, enrolled in a multicenter study where conventional sanitation methods were replaced with PCHS, were included in the analysis. The study period included a 6-month observation for each sanitation type. Surface microbiota AMR was analyzed using microarray, nested PCR, antibiogram, and microdilution tests. Drug consumption data and related costs were obtained from the medical records of all hospitalized patients affected by HAIs. RESULTS: PCHS use was associated with up to 99% decrease of the AMR genes harbored by surface hospital microbiota, independently of the resistance types originally present in each individual setting (Pc <0.01). Functional assays confirmed the molecular data, demonstrating a 33%-100% decrease of resistant strains depending on the antibiotic type. Antimicrobial drug consumption associated with HAI onset showed a global 60.3% decrease, with a 75.4% decrease of the associated costs. CONCLUSION: The spread of AMR in the hospital environment can be limited by the use of sanitation methods to remodulate the hospital microbiota, leading to lower antimicrobial consumption and costs. This approach might be considered as part of broader infection prevention and control strategies.

Introduction of NGS in Environmental Surveillance for Healthcare-Associated Infection Control.

The hospital environment significantly contributes to the onset of healthcare associated infections (HAIs), representing the most frequent and severe complications related to health care. The monitoring of hospital surfaces is generally addressed by microbial cultural isolation, with some performance limitations. Hence there is need to implement environmental surveillance systems using more effective methods. This study aimed to evaluate next-generation sequencing (NGS) technologies for hospital environment microbiome characterization, in comparison with conventional and molecular methods, in an Italian pediatric hospital. Environmental samples included critical surfaces of randomized rooms, surgical rooms, intensive care units and delivery rooms. The resistome of the contaminating population was also evaluated. NGS, compared to other methods, detected with higher sensitivity the environmental bacteria, and was the only method able to detect even unsearched bacteria. By contrast, however, it did not detect mycetes, nor it could distinguish viable from dead bacteria. Microbiological and PCR methods could identify and quantify mycetes, in addition to bacteria, and PCR could define the population resistome. These data suggest that NGS could be an effective method for hospital environment monitoring, especially if flanked by PCR for species identification and resistome characterization, providing a potential tool for the control of HAI transmission.

Characterization of biodegradation in a 17th century easel painting and potential for a biological approach.

It is important to characterize the microorganisms involved in biodeterioration processes to understand their effects on cultural assets and to define an efficient strategy for protecting artworks, monuments, and buildings from microbiological recolonization. In this study, we analyzed the microbial communities dwelling on the verso (front) and recto (back) sides of a 17th century easel painting attributed to Carlo Bononi, an Italian artist of the first Baroque period. Cultivable bacteria and fungi colonizing the painting were isolated and identified in order to characterize the microbial community possibly involved in deteriorating the pictorial layer of the painting. The isolated bacterial strains belonged to the Staphylococcus and Bacillus genera. Furthermore, culture-dependent techniques and SEM/EDS analyses revealed the presence of filamentous fungi of the genera Aspergillus, Penicillium, Cladosporium, and Alternaria. The chemical compositions of pigments were consistent with typical 17th century paintings, and some of the identified pigments, namely red lac and red and yellow earths, could be exploited as nutrient sources by painting-associated microorganisms. The study also evaluated, in vitro, the potential decontaminating activity of a biocompound, containing spores of Bacillus subtilis, Bacillus pumilus, and Bacillus megaterium. The results indicated the ability of this biocompound to counteract the growth of contaminating microorganisms that are potentially dangerous to the painting, suggesting the potential use of these microorganisms to prevent biodeterioration of artworks.

Efficient removal of hospital pathogens from hard surfaces by a combined use of bacteriophages and probiotics: potential as sanitizing agents.

PURPOSE: Many hospital-acquired infections (HAIs) can be transmitted by pathogens contaminating hospital surfaces, not efficiently controlled by conventional sanitation, which can indeed contribute to the selection of MDR strains. Bacteriophages have been suggested as decontaminating agents, based on their selective ability to kill specific bacteria. However, there are no data on their stability in detergents and their potential use in routine sanitation. On the other hand, a probiotic-based sanitation system (Probiotic Cleaning Hygiene System, PCHS) was recently shown to stably reduce pathogens on treated surfaces. However, its action is not specific and slow, being based on competitive antagonism. This work aimed to assess the effectiveness of a combined use of phages and PCHS in removing HAI-associated pathogens from different hard surfaces. MATERIALS AND METHODS: The decontamination ability of phages in PCHS was tested in vitro and in situ, against drug-susceptible or resistant Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa strains, and using bacterial densities similar to those detected on hospital surfaces. RESULTS: Phages targeted efficiently all tested bacteria, maintaining their full activity when added to the PCHS detergent. Notably, the combined use of phages and PCHS not only resulted in a rapid reduction (up to >90%) of the targeted pathogens, but also, due to the stabilizing effect of probiotics, the pathogens were maintained at low levels (>99%) at later times too, when instead the effect of phages tends to diminish. CONCLUSION: These results suggest that a combined biological system might be successfully used in hospital sanitation protocols, potentially leading to effective and safe elimination of MDR pathogens from the hospital environment.

[Percutaneous treatment of a primary renal aspergilloma in a patient with AIDS]. / Percutaneous treatment of a primary renal aspergilloma in a patient with AIDS.

Primary renal aspergillosis is a very rare complication of AIDS which usually have fatal outcome (53% of mortality). The immune status of the patient and the early and correct therapeutic approach are the main factors that predict disease advancement. The new antiretroviral therapies improve the CD4 cell count and permit to treat these patients as immuno-competent. The local approach with antifungal drugs instillations, percutaneous drainage combined with systemic antifungal therapy can increase the number of patients that may benefit from a conservative treatment. We report a case of a 44-year-old homosexual patient with AIDS since 1991 in stage IVc (CDC--Centers for Disease Control and Prevention) in antiretroviral treatment. In September 1999 he came because of left low back pain. Laboratory data showed leucocytosis. Urinalysis revealed the presence of white and red blood cells and a negative urine culture. The abdominal ultrasound examination, the intravenous pyelogram and finally the computerized tomography confirm the presence of solid material that occupied the renal pelvis and the middle and superior caliceal group of the left kidney associated with lymph nodes enlargement. An echo-guided needle aspiration allowed us to identify Aspergillus fumigatus. Local instillations with amfotericina B through a nephrostomy and systemic antifungal drugs resolved the urinary infection.