Corrigendum: Application of a Medical Diode Laser (810 nm) for Disinfecting Small Microbiologically Contaminated Spots on Degraded Collagenous Materials for Improved Biosafety in Objects of Exceptional Historical Value From the Auschwitz-Birkenau State Museum and Protection of Human Health.

[This corrects the article DOI: 10.3389/fmicb.2020.596852.].

Effective microbiological decontamination of dental healing abutments colonised with Rothia aeria by a diode laser as a helpful step towards successful implantoprosthetic therapy.

The aim of the study was to find variant of diode laser (λ = 810 nm) irradiation, which ensures elimination of unwanted microorganisms, including Rothia aeria, from dental healing abutments, and consequently accelerates process of wound healing in implantologically treated patients. The scope of the study included identification of the most contaminated areas on healing abutments, identification of microorganisms inhabiting various environments of oral cavities, assessment of effectiveness of various laser decontamination parameters against detected microorganisms (preliminary studies) and assessment of wound healing in patients after applying abutments with low roughness and optimal variant of laser irradiation (clinical studies). Imaging of surfaces of the healing abutments was performed using vertical scanning interferometry, scanning electron microscopy and optical microscopy. Microorganisms inhabiting the healing abutments, teeth and saliva from tested patients were identified using matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry. Three programmes of near-infrared diode laser at average powers of 1.00-3.84 W with two variants of exposure time were used for optimisation of laser parameters. Observation of wound healing was performed for 100 patients during 20 days after installation of abutments. On surfaces of the used healing abutments, a large number of microorganisms, with a predominance of R. aeria, were found. Irradiation with periimplantitis surgical programme for 30 s resulted in 99-100% reduction in the number of R. aeria and other microorganisms, depending on type of abutment (in vivo). The use of diode laser in the selected variant accelerates wound healing and provides complete elimination of pathogenic R. aeria and other microorganisms inhabiting surfaces of the healing abutments without marks.

Decontamination of microbiologically contaminated abiotic porous surfaces in an oral surgery clinic using vaporised hydrogen peroxide (VHP).

PURPOSE: The aims of the study were to identify microorganisms, including those in the VBNC state, inhabiting porous surfaces in oral surgery offices and to assess the biocidal effectiveness and impact of 300 ppm vaporised hydrogen peroxide (VHP) for 20 min on decontaminated materials. METHODS: From the surfaces of textured armrests of dental chairs, pinewood doors and window frames and cotton medical aprons, 30 swabs were taken with moistened sponges. The identification of isolated microorganisms was performed using molecular methods with MALDI-TOF MS, DNA Sanger sequencer and Illumina MiSeq. To evaluate the impact of VHP decontamination (independent variable) on the number of microorganisms (response variable) ANOVA and LSD tests were used. After application of 10 processes of VHP decontamination, changes in the properties of the materials were assessed using FTIR spectroscopy, SEM microscopy and XPS spectrometry. RESULTS: The concentration of microorganisms was 101-104 CFU/100 cm2 on the tested surfaces and 102 CFU/m3 in the air. Twenty species of bacteria, one yeast and 16 filamentous fungi were identified, with the predominance of Bacillus, Staphylococcus, Alternaria, Aspergillus and Penicillium. Moreover, Janthinobacterium, Acremonium, Aureobasidium, Coprinellus and Cosmospora in the VBNC state were metagenomically detected. VHP decontamination resulted in a reduction in the majority of tested microbial strains by a minimum of 3 log, and all tested mixed cultures inhabiting porous surfaces were above 98% and in the air, 100%. VHP decontamination did not affect the structural and morphological properties of cotton fibres, wood or stainless steel. CONCLUSIONS: VHP decontamination at a concentration of 300 ppm for 20 min can be used for the holistic disinfection of air, surfaces and equipment in oral surgery offices.

Prevention of SARS-COV-2 coronavirus spread at the Auschwitz-Birkenau State Museum in Poland. The most visited Memorial site in the world during the COVID-19 pandemic.

INTRODUCTION: At the Auschwitz-Birkenau State Museum (A-BSM) actions have been undertaken to effectively protect employees and minimise risk of SARS-CoV-2 coronavirus spreading from the beginning of the COVID-19 epidemic. AIM OF THE ARTICLE: The aim was to present the actions, instructions and procedures introduced at the A-BSM to provide information how to deal with pandemic caused by the SARS-CoV-2 coronavirus in institutions taking care of cultural heritage before and after closure of the Museum for visitors and after reopening. MATERIALS AND METHODS: The described activities were developed at the Museum by a specially established Expert Team. RESULTS: Groups of employees and places in which they were most exposed to contact with visitors and, as a consequence, at the highest risk of getting infected, were characterised. The employees were provided with personal protective equipment, and at the Museum site, devices essential for maintaining the microbiological cleanliness of the rooms, were placed. In the next stage, instructions and procedures for particular groups of employees were prepared. Visitors were educated about the need of taking precautions and were allowed to disinfect in several places at the Memorial Site. Steps to reduce attendance at this time has also been taken. Procedures for employees of the A-BSM were developed in such way that they can also be used after reopening of the Museum for visitors. CONCLUSIONS: The actions which ensured the microbiological safety of the A-BSM employees, brought satisfying results. In more than 21 days after closing of the Museum for visitors, no cases of SARS-CoV-2 infection or COVID-19 were found among employees, despite a very high threat.

Application of a Medical Diode Laser (810 nm) for Disinfecting Small Microbiologically Contaminated Spots on Degraded Collagenous Materials for Improved Biosafety in Objects of Exceptional Historical Value From the Auschwitz-Birkenau State Museum and Protection of Human Health.

The research aim was to optimize the operating parameters of a diode laser irradiation for the effective disinfection of degraded collagenous materials. Historical leather shoes stored at the Auschwitz-Birkenau State Museum in Oswiecim (Poland) were the main study objects. Surfaces of contaminated small spots occurring on the degraded materials were sampled with moistened swabs and microbiologically examined using the molecular techniques MALDI-TOF MS, 16S rRNA, and NGS sequencing. The surfaces were colonized by bacteria with 106 CFU/100 cm2 and 104 CFU/100 cm2 by fungi, on average. Microorganisms of the genera Bacillus and Penicillium were predominant. The effectiveness of the laser treatment was assessed for the new and degraded collagenous materials against isolated environmental strains using four variants of exposure time and number of repetitions. 0.3 W/CW 2 × 2 min variant was the most effective and also did not noticeably change the color of the treated samples. The variant caused a reduction in the numbers of microorganisms by 96-100%. After 1 month, four types of leather were subjected to comprehensive physico-chemical analyses. SEM and FTIR techniques confirmed that laser irradiation in the selected optimal variant did not affect the surface morphology and collagen structure, while XPS technique enabled detection of subtle changes in non-historical protective coatings on the surfaces of tested degraded historical materials.