Preservation fluids of heritage anatomical specimens - a challenge for modern science. Studies of the origin, composition and microbiological contamination of old museum collections.

Anatomical museums preserve specimens of great historical value and undiscovered scientific potential. However, frequently these collections lack documentation of the techniques of preparation and the composition of preservative substances (conservation principles). This poses a huge problem for the care and preservation of these materials, more so because understanding this issue requires knowledge of fundamentals from different scientific disciplines. The aim of the research was to obtain information about the composition of substances used to preserve historic specimens, as well as to conduct a microbiological assessment of the specimens to detect possible factors causing their deterioration. Furthermore, we wanted to fill an existing gap in the literature, as there is a lack of reports on analytical methods that could be successfully applied by anatomists involved in the daily care of museum collections in human anatomy departments. The starting point was the analysis of the sources and history of the collections, on which basis the choice of research methods was made. Methods based on simple chemical reactions and specialised methods (such as gas chromatography-tandem mass spectrometry, Fourier transform infrared spectroscopy, inductively coupled plasma optical emission spectroscopy) were used in the analyses of the composition of fluids. Microbiological analyses were based on culture and isolation methods, analysis of microscopy slides and matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry analysis. As a result of these analyses, some components of the preservative mixtures and their concentrations were determined. The presence of methanol, ethanol, formaldehyde and glycerol was detected, among other chemicals. The concentrations of these substances were different between the samples and their determination required the use of a variety of methods suitable for the individual components of the preservative mixture. In microbiological tests, both bacteria and fungi were isolated from swabs taken from anatomical specimens. The bacterial flora was less numerous than the fungal flora. Among the bacteria, environmental Gram-positive Bacillus cereus, Bacillus thuringiensis and a rare bacterium of the Cupriavidus genus were isolated, whereas among the fungal organisms, the yeast-like fungi Candida boidinii and Geotrichum silvicola as well as mould fungi Penicillium sp. and Fusarium sp. were detected. However, the microscopic evaluation showed a greater diversity of microorganisms, which may be related to the fact that many environmental bacteria cannot be cultured using classical methods, but can be observed under the microscope. The results of the research made it possible to draw conclusions about the mutual influence of physical, chemical, and microbiological factors on the condition of historical anatomical specimens. In the course of the research, information was obtained on the processes which could have taken place during the storage of these collections. Maintaining the integrity of a container housing a preserved anatomical specimen has a major impact on maintaining the concentration of preservative fluid and keeping the specimen environment sterile. Many conservation procedures for historical specimens carried out nowadays pose a risk of destroying valuable specimens, as well as a health risk for the person carrying out the work. The exploration of the topic of conservation of anatomical specimens, especially those that lack documentation of their origin, is a key issue in current research on historical collections of anatomical specimens.

Pet feeding habits and the microbiological contamination of dog food bowls: effect of feed type, cleaning method and bowl material.

BACKGROUND: Safe pet feeding practices and food bowl hygiene measures are important for minimising the risk of microbiological contaminations in the domestic environment. This study compares the practices reported by dog and cat caregivers, and investigates whether cleaning method, feed type or bowl material affects the microbiological contamination of dog food bowls. RESULTS: Data from 351 dog caregivers and 186 cat caregivers were collected via an online survey. The majority of dogs (70.7%) were fed twice daily, whereas cats (43%) were mostly fed ad libitum. The most common material for dog food bowls was metal (67.1%) versus plastic (38.1%) and metal (37.6%) for cats. Dog food bowls were most frequently cleaned after each meal (35.7%); whereas for cats, 21.5% were cleaned after each meal, 22.7% once a day and 19.3% 2-3 times a week. Total mesophilic aerobic bacteria counts (TMABc), Enterobacteriaceae counts and pathogenic bacteria (Salmonella spp., Campylobacter spp., Verotoxigenic E. coli [VTEC]) were assessed for 96 dog food bowls. TMABc were higher in metal vs. plastic bowls (p < 0.001) and in those used for wet food vs. dry food (p = 0.0397). Enterobacteriaceae counts were higher in bowls washed by hand vs. dishwasher (p = 0.0515), whereas no differences were found between hand washing vs. dry wiping. Salmonella spp., Campylobacter spp. or E. coli VTEC contaminations were not detected. CONCLUSIONS: The surveyed Italian dog and cat caregivers reported different habits concerning feeding frequency, food bowl material and cleaning frequency. Wet food and metal bowls were associated with higher levels of microbiological contamination of dog food bowls. Furthermore, in relation to wet washing methods, contaminations were likely to be greater following hand washing than they were following the use of a dishwasher. Practical guidelines for safe feeding practices and hygiene measures are needed to minimise the risk of microbiological contaminations in domestic environments.

Evaluation of groundwater quality with microbiological and physicochemical parameters in Bartin, Turkey.

In this study, the physicochemical and microbiological quality of groundwater samples was investigated in rainy and dry periods. Forty samples were collected from 10 sampling points. TDS, EC, color, turbidity, NO3, SO4, PO4, Cl, total hardness, E. coli, and F. streptococci analyses were performed. Cl, TH, and NO3 were higher in the rainy period unlike TDS, EC, SO4, and PO4. Physicochemical parameters did not exceed the acceptable values reported for drinking waters in TS/WHO. However, groundwater samples were not suitable for drinking water in terms of microbiological parameters. Both bacteria were found in higher numbers in the dry period. However, E. coli was more abundant in the dry period in contrast to F. streptococci. According to the nitrate/Cl ratio and other analyses (correlation matrix and principal component analysis) groundwater quality was affected by many sources. The results of analytic and statistical analyzes showed that F. streptococci is mostly related to animal waste unlike E. coli. According to the EC/FS ratio, microbiological pollution in rural areas was affected by animal wastes in both periods. On the other hand, animal waste in the urban areas may be effective during the rainy period. PCA and correlation matrix also confirmed these results. According to PCA results, groundwater quality may be affected by geogenic sources, fecal sources, and use of fertilizer in the study area. According to WQI, 5% and 16% of the groundwater samples were not found suitable as drinking water in dry and rainy periods, respectively.

The potential application of supercritical CO2 in microbial inactivation of food raw materials and products.

The purpose of this study was to review the possibility of using supercritical CO2 as a green and sustainable technology for microbial inactivation of raw material for further application in the food industry. The history of the development of supercritical CO2 microbial inactivation has been widely described in this article. The fundamental scientific part of the process like mechanism of bactericidal action of CO2 or inactivation of key enzymes were characterized in detail. In summary, this study provides an overview of the latest literature on the use of supercritical carbon dioxide in microbial inactivation of food raw materials and products.

A reliable method to avoid contamination during cartilage graft preparation in septorhinoplasty.

PURPOSE: The aim of the study is to determine the risk of contamination in the cartilage graft materials prepared on the swester table and those prepared in a sterile package, and to reveal a more reliable method by performing the microbiological examination of these materials. METHODS: Cartilages removed from the nasal septum were divided into four pieces. The first part (Sample A) was directly placed into the medium. Sample B was prepared by being crushed in a sterile package. Sample C was prepared on the auxiliary swester table, and Sample D was prepared on the main swester table actively used by surgery team. All samples were transferred in a 1 ml brain heart(BH) liquid medium. From each BH medium, 100 µl culture was performed on blood agar, eosin-methylene blue-lactose-sucrose agar and chocolate agar. RESULTS: Bacterial growth was detected in 2 of the samples A, in 4 of the samples B, in 24 of the samples C, and in 36 of the samples D. The number of patients with bacterial growth in the samples C and/or D despite no growth in the sample B was 35. When the samples A/B and C/D were compared in terms of bacterial growth, a significant difference was found in all matchings (p < 0.001 for all comparisons).  CONCLUSION: These findings showed that preparation of the cartilage grafts on the swester table was extremely risky for microbiological contamination. Arslan and his colleagues suggest that preparing a graft material in a sterile package is extremely simple, cheap, and it also reduces contamination risk significantly.

Microbiological monitoring of heater-cooler unit to keep free of Mycobacterium chimaera infection.

INTRODUCTION: The association of Mycobacterium chimaera infection in patients undergoing cardiopulmonary bypass (CPB) with the use of heater-cooler units (HCU) has been reported in various literature. We described microbiological monitoring and the extent of microbiological contamination of HCUs utilized in our centre and strategies employed to reduce the high microbial load. METHODS: Since August 2016, we have been following the new Instructions for Use from the manufacturer for the cleaning and disinfection of three units of Stöckert 3T and four units of Stöckert 1T HCU at the National Heart Centre Singapore. Microbiological monitoring began in January 2017 and included acid-fast bacilli (AFB) culture, Pseudomonas aeruginosa, total colony and total coliform count. Methods, such as increasing disinfection frequency and making the HCU inactive by keeping it empty in storage, were used to reduce the high colony count. RESULTS: All three units of Stöckert 3T and two units of Stöckert 1T were contaminated with Mycobacterium chimaera. Pseudomonas aeruginosa and total coliform count were consistently <1 colony-forming unit (CFU)/100 mL in every water sample of each HCU. High colony counts were encountered initially in all units. Step-up frequency of disinfection was found to be not as effective as keeping the HCU inactive in bringing the total colony count to an acceptable level. CONCLUSIONS: All monitoring and maintenance measures of HCUs need to be established and maintained to mitigate potential infection risks to patients. Strict adherence to all cleaning and disinfection processes and keeping the HCU inactive maintained the water quality of the HCU at acceptable levels.

Microbiological contamination in donor corneas preserved for medium-term.

To evaluate the characteristics of microbiological contamination in donor corneas preserved for medium-term. A total of 82 donated corneas from June 1, 2014 to November 30, 2014 were retrospectively analyzed. The corneas were preserved in cornea chambers medium-term solution at 4-8 °C for keratoplasty. After removal of the central corneas for transplantation, the corneoscleral rims were put back into the medium for 1 month at room temperature (20-25 °C). The suspicious contaminated storage solutions indicated with transparency or color change were examined with bacteria and fungi cultivation for strain identification. The data collected included gender, age, procurement site and causes of death of donors, and follow-up of recipients. Statistical analysis was performed using Microsoft Excel and SPSS 24.0. Significance level was set at a P value < 0.05. The overall pathogen positive rate was 9.8% (n = 8), including 7 (87.5%) fungi and 1 (12.5%) bacteria. They were 2 (2.44%) Fusarium, 2 (2.44%) Chromomycosis, 1 (1.22%) Candida albicans, 1 (1.22%) Aspergillus versicolor, 1 (1.22%) Acremonium species, and 1 (1.22%) Enterococcus. 5 contaminated corneas were used for penetrating keratoplasty; although four out of five (80%) had not been given antifungal drugs during more than 6 months following-up period, none of the recipients was infected with a graft. Donor age (P = 0.839), gender (P = 0.062), procurement sites (P = 0.713) and cause of death (P = 0.711) had no statistically significant influence on the contamination rate. All donor corneas have a possibility of microbiological contamination. Strict tissue preservation protocol but not antifungal drugs following keratoplasty seems necessary to prevent graft infection.

Are dietary supplements containing plant-derived ingredients safe microbiologically?

Dietary supplements, particularly those containing ingredients of natural origin, may contain microbiological contaminants, both bacterial and fungal. The present study evaluated the microbiological purity of selected dietary supplements containing plant-based ingredients before their release to the market, as well as raw materials of plant origin which are used in the production of such supplements. A total of 122 samples of supplements and 30 materials of plant origin were studied, with 92.1% exhibiting different degrees of bacterial contamination. Eight samples (5.3%) were contaminated by aerobic bacteria in amounts exceeding 105 CFU/g. Five (3.3%) of the studied supplements were found to contain bacteria from the family Enterobacteriaceae at a level exceeding 103 CFU/g. Furthermore, a considerable proportion of the studied samples (86.8%) contained fungal contamination. Microbiological contamination may contribute to a deterioration in quality and stability of dietary supplements. In addition, high levels of pathogenic bacteria and microorganisms may pose a risk to consumers.

ATP bioluminescence assay for evaluating cleaning practices in operating theatres: applicability and limitations.

BACKGROUND: Environmental cleaning practice plays an important role in reducing microbial contamination in hospital surfaces and contributes to prevent Healthcare Associated Infections. Adenosine Triphosphate (ATP) bioluminescence assay is a commonly used method for assessing environmental cleanliness on healthcare surfaces. This study tested the feasibility of using ATP-bioluminescence assay for evaluating the efficiency of cleaning procedures in the operating theatre settings, comparing the ATP-bioluminescence test with the traditional culture method. METHODS: The surfaces of 10 operating rooms of two public hospitals (140 samples in total) were examined "at rest", in two moments of the same daily session: before the first scheduled operation (Pre), and before the second, after a clean environment was re-established (Post). Surface contamination was assessed using the cultural method to detect Total Viable Counts (TVC36°C) and ATP-bioluminescence assay (RLU). RESULTS: The examined surfaces presented very low TVCs (geometric means: 1.8 CFU/plate; IC95%: 1.6-2.0), always compliant with the relative reference standards. No statistical correlation was found between ATP values and TVCs. However, considering the results in terms of general evaluation of hygienic quality of surfaces, the two methods were consistent in identifying the most contaminated areas (Hospital A > Hospital B; Pre > Post; most contaminated surfaces: scialytic lamp). Furthermore, the ATP mean values showed a progressive increase from surfaces with TVC = 0 to surfaces with TVC > 15 CFU/plate. CONCLUSIONS: Although not an alternative to cultural methods, the ATP-bioluminescence-assay can be a useful tool to measure the efficiency of cleaning procedures also in environments with very low microbial counts. Each health facility should identify appropriate reference values, depending on the devices used and on the basis of the analysis of the data collected through spatial and temporal sampling series. By providing a rapid feedback, the ATP-assay helps to increase the awareness of operators and allows immediate action to be taken in critical situations.

Analysis of potential contamination factors in musculoskeletal tissues.

Tissue Banks have become the main source for bone grafts, due to preference for homologous tissues. Notwithstanding the use of aseptic techniques for procurement of tissues and judicious selection of donors, microorganisms are frequently found in procured bones. Purpose of this study is to evaluate the factors that increase safety of procurement and minimize discard of procured tissues. Microbiological contamination was analyzed in 1271 musculoskeletal tissues removed from 138 multi-organ donors over a period extending from 2006 to 2016. Effects of various risk factors related with contamination were estimated using a logistic regression model. Microbiological contamination rate in the tissues was 17.1%; low pathogenic microorganisms were cultivated in 12.9% of the tissues, while highly pathogenic ones were cultivated in 4.2% of the tissues. Evolution of one single team was monitored during that period, verifying a fall in the general contamination level from 22.5 to 9.2%. Absence of antibiotics increased low pathogenic contamination risk. Every additional day in intensive care unit (ICU) increased the risk of highly pathogenic contamination. Time elapsed between death and the beginning of removal procedures was found to be relevant for both low pathogenic and highly pathogenic microorganisms. Among the studied factors, the following contributed for a significant increase in contamination by microorganisms in removed tissues: lack of use of prophylactic antibiotic therapy in donors, quantity of removed tissues, length of admission in ICU and the time elapsed between aortic clamping and beginning of the removal procedure.

Monitoring Salmonella, Campylobacter, Escherichia coli and Staphylococcus aureus in traditional free-range 'Label Rouge' broiler production: a 23-year survey programme.

AIM: 'Label Rouge' broiler free-range carcasses have been monitored since 1991, and broiler flocks since 2010, for contamination by the main foodborne zoonotic bacteria. METHODS AND RESULTS: Initially, the monitoring plan mainly focused on the surveillance of Salmonella, and on indicators of the overall microbiological quality of free-range broiler carcasses such as Staphylococcus aureus and coliforms, but was extended in 2007 to include Campylobacter enumeration on carcasses and in 2010, to Salmonella in the environment of live birds. Salmonella contamination of free-range broiler carcasses rose to a peak of 16% in 1994 but less than 1% of carcasses are now regularly found to be positive. Indicators of the overall microbiological quality of carcasses are also improving. These results correlate with the low prevalence of Salmonella in free-range broiler breeding and production flocks, and with the continuous improvement of hazard analysis and critical control points in slaughterhouses, the implementation of a good manufacturing practice guide since 1997 and the application of EU regulations on Salmonella since 1998 in France. Regarding Campylobacter counts on carcasses, the situation has been improving continuously over the last few years, even if 2·5% of the carcasses are still contaminated by more than 1000 Campylobacter per g of skin. CONCLUSIONS: Although the current control system focusing on Salmonella is based on firm epidemiologic data and offers effective means of control (e.g. slaughtering of positive breeder flocks), existing information on Campylobacter makes it more difficult to formulate an effective control plan for free-range broilers, due to their particular exposure to environmental contamination. SIGNIFICANCE AND IMPACT OF THE STUDY: This long-term surveillance programme provided an extended view of the evolution of the contamination of free-range broilers and a direct measurement of the impact of mandatory and profession-driven interventions on the microbiological quality of carcasses.

Urban groundwater quality in sub-Saharan Africa: current status and implications for water security and public health.

Groundwater resources are important sources of drinking water in Africa, and they are hugely important in sustaining urban livelihoods and supporting a diverse range of commercial and agricultural activities. Groundwater has an important role in improving health in sub-Saharan Africa (SSA). An estimated 250 million people (40% of the total) live in urban centres across SSA. SSA has experienced a rapid expansion in urban populations since the 1950s, with increased population densities as well as expanding geographical coverage. Estimates suggest that the urban population in SSA will double between 2000 and 2030. The quality status of shallow urban groundwater resources is often very poor due to inadequate waste management and source protection, and poses a significant health risk to users, while deeper borehole sources often provide an important source of good quality drinking water. Given the growth in future demand from this finite resource, as well as potential changes in future climate in this region, a detailed understanding of both water quantity and quality is required to use this resource sustainably. This paper provides a comprehensive assessment of the water quality status, both microbial and chemical, of urban groundwater in SSA across a range of hydrogeological terrains and different groundwater point types. Lower storage basement terrains, which underlie a significant proportion of urban centres in SSA, are particularly vulnerable to contamination. The relationship between mean nitrate concentration and intrinsic aquifer pollution risk is assessed for urban centres across SSA. Current knowledge gaps are identified and future research needs highlighted.

Les ressources en eaux souterraines sont des sources importantes d'eau potable en Afrique, et elles sont d'une énorme importance pour les êtres vivants en milieu urbain et pour le soutien d'une gamme diversifiée d'activités commerciales et agricoles. Les eaux souterraines jouent un rôle important en améliorant la santé en Afrique sub-saharienne (ASS). 250 millions de personnes environ (40% du total) vivent dans des centres urbains à travers l'ASS. L'ASS a connu une expansion rapide de ses populations urbaines depuis les années 1950, avec une augmentation à la fois des densités de population et de leur extension géographique. Les estimations prévoient un doublement de la population urbaine de l'ASS entre 2000 et 2030. L'état qualitatif des ressources en eau souterraine urbaines peu profondes est souvent très pauvre du fait de l'insuffisance de la gestion des déchets et de la protection de la ressource, et pose un risque sanitaire significatif pour les utilisateurs, alors que des ressources plus profondes captées par forage fournissent souvent une source importante d'eau potable de bonne qualité. Etant donné la croissance de la demande future de cette ressource limitée, ainsi que le changement climatique potentiel dans cette région dans le futur, une compréhension détaillée de la quantité et la qualité de cette ressource est exigée pour son utilisation durable. Cet article fournit une évaluation complète de l'état qualitatif, à la fois microbien et chimique, des eaux souterraines urbaines en ASS à travers une gamme de contextes hydrogéologiques et de différents types de point d'eaux souterraines. Les terrains du sous-sol de faible emmagasinement, qui sont situés sous une proportion significative de centres urbains en ASS, sont particulièrement vulnérables à la contamination. Le rapport entre la concentration moyenne en nitrate et le risque intrinsèque de pollution des aquifères est évalué pour les centres urbains de l'ASS. Des lacunes actuelles en matière de connaissances sont identifiées et les besoins de recherches futurs sont mis en évidence.

Los recursos hídricos subterráneos son una fuente importante de agua potable en África y son sumamente importantes para mantener los medios de subsistencia urbanos y para apoyar una amplia gama de actividades comerciales y agrícolas. El agua subterránea tiene un papel importante en la mejora de la salud en el África Subsahariana (SSA). Se calcula que 250 millones de personas (40% del total) viven en centros urbanos en el África Subsahariana. El SSA ha experimentado una rápida expansión en las poblaciones urbanas desde la década de 1950, con el aumento de la densidad de población, así como la ampliación de la cobertura geográfica. Las estimaciones sugieren que la población urbana en África Subsahariana se duplicará entre 2000 y 2030. El estado de calidad del agua subterránea somera es a menudo muy pobre debido a la gestión inadecuada de los desechos y de la protección de las fuentes, representando un riesgo significativo para los usuarios, mientras que los pozos más profundos proporcionan una fuente importante de agua potable de buena calidad. Dado el crecimiento de la demanda futura de este recurso finito, así como los cambios potenciales en el clima futuro en esta región, una comprensión detallada de su cantidad y calidad es necesaria para utilizar este recurso de manera sostenible. Este artículo ofrece una evaluación integral del estado de la calidad del agua, tanto microbiana como química, del agua subterránea urbana en el SSA a lo largo de una serie de terrenos hidrogeológicos y diferentes tipos de puntos de agua subterránea. Los basamentos de bajo almacenamiento, que subyacen a una proporción significativa de los centros urbanos del África Subsahariana, son particularmente vulnerables a la contaminación. Se evalúa la relación entre la concentración media de nitratos y el riesgo intrínseco de contaminación acuífera para los centros urbanos a través de la SSA. Se identifican las deficiencias actuales de conocimientos y se destacan las necesidades de futuras investigaciones.

As águas subterrâneas são fontes importantes de água para consumo na África, e são amplamente importantes para sustentar o modo de vida urbano e dar suporte a uma amplitude diversa de atividades comerciais e agrícolas. As águas subterrâneas têm um papel importante no desenvolvimento da saúde na África subsaariana (ASS). São estimadas 250 milhões de pessoas (40% do total) vivendo nos centros urbanos na ASS. ASS tem vivenciado uma rápida expansão na população urbana desde os anos 50, com aumento das densidades populacionais assim como expansão da cobertura geográfica. As estimativas sugerem que a população urbana na ASS dobrará entre 2000 e 2030. As condições de qualidade dos aquíferos livres em áreas urbanas estão frequentemente muito pobres por causa do gerenciamento de perdas e proteção das fontes inadequados, e apresenta um risco significativo à saúde dos usuários, enquanto poços mais profundos frequentemente fornecem fontes importantes de água potável de boa qualidade. Dado o crescimento na demanda futura desse recurso finito, assim como mudanças potenciais no clima futuro da região, um entendimento detalhado da sua quantidade e qualidade é necessário para o uso sustentável deste recurso. Esse estudo fornece uma avaliação compreensiva das condições de qualidade da água, tanto microbiológica quanto química, das águas subterrâneas urbanas na ASS por uma gama de terrenos hidrogeológicos e diferentes tipos pontuais de águas subterrâneas. Terrenos de menor armazenamento de base, que fundamentam uma porção significante dos centros urbanos da ASS, são particularmente vulneráveis a contaminação. A relação entre a concentração média de nitrato e o risco intrínseco de poluição do aquífero é avaliado para os centros urbanos na ASS. Lacunas do conhecimento atual foram identificadas e destaca-se a necessidade de pesquisas futuras.

Humidifiers for oxygen therapy: what risk for reusable and disposable devices?

INTRODUCTION: Nosocomial pneumonia accounts for the vast majority of healthcare-associated infections (HAI). Although numerous medical devices have been discussed as potential vehicles for microorganisms, very little is known about the role played by oxygen humidifiers as potential sources of nosocomial pathogens. The purpose of this research was to evaluate the safety of the reuse of humidifiers by analysing the rate of microbial contamination in reusable and disposable oxygen humidifiers used during therapy, and then discuss their potential role in the transmission of respiratory pathogens. METHODS: Water samples from reusable and disposable oxygen humidifiers were collected from different wards of the University Hospital of Messina, Italy, where nosocomial pneumonia has a higher incidence rate due to the "critical" clinical conditions of inpatients. In particular, we monitored the Internal Medicine and Pulmonology wards for the medical area; the General Surgery and Thoracic and Cardiovascular Surgery wards for the surgical area and the Intensive Care Unit and Neonatal Intensive Care Unit for the emergency area. The samples were always collected after a period of 5 days from initial use for both types of humidifiers. Samples were processed using standard bacteriological techniques and microbial colonies were identified using manual and automated methods. RESULTS: High rates of microbial contamination were observed in samples from reusable oxygen humidifiers employed in medical (83%), surgical (77%) and emergency (50%) areas. The most relevant pathogens were Pseudomonas aeruginosa, amongst the Gram-negative bacteria, and Staphylococcus aureus, amongst the Gram-positive bacteria. Other pathogens were detected in lower percentage. The disposable oxygen humidifier samples showed no contamination. CONCLUSIONS: This research presents evidence of the high rate and type of microbial contamination of reusable humidifiers employed for oxygen therapy. These devices may thus be involved in the transmission of potential pathogens. It could be important, for the prevention of nosocomial pneumonia, to replace them with singleuse humidifiers for which the absence of microbial contamination has been confirmed.

Microbiological quality of non-sterile pharmaceutical products.

In microbiological terms, pharmaceutical products can be divided into two groups: sterile and non-sterile. Non-sterile drugs must satisfy the appropriate microbiological purity criteria which are included in pharmacopoeial monographs. Pharmacopoeial studies are prepared specifically with a view to ensuring that the medicinal product is therapeutically effective and safe for the patient. The analysis comprised the results of microbiological purity tests performed before the products are marketed. Total of 1285 samples of non-sterile drugs manufactured by different pharmaceutical plants in Polish were taken into study. The microbiological quality of drugs was assessed in accordance with the criteria included in the European Pharmacopoeia (EP). An analysis of test results demonstrated that the percentage of non-compliant samples was 1.87%. The groups of drugs, which the most often did not satisfy EPs' requirements, were drugs containing raw materials of natural origin (5.7%). The samples of studied drugs that did not meet the criteria contained in EP, exceed the maximum allowable microbiological count limits and contained microbes whose presence is prohibited. The most common non-compliance was the excessive levels of the maximum acceptable fungal count (n = 12) and the excessive the maximum acceptable aerobic microbial count (n = 10).

Microbiological contamination of dried and lyophilized garlic as a potential source of food spoilage.

Garlic is valued more for its flavoring and used in a wide variety of foods. In food technology, fresh garlic is not used, but instead its processed forms, most often dried and lyophilized, are utilized. The quality and safety of the final product largely depends on their microbiological quality. This research has provided information about effect of garlic fixation methods and provided information about effect of microbiological contamination of garlic used as a spice for quality of garlic mayonnaise sauce. The authors decided to undertake studies following a report from one of the manufacturers of garlic sauces on product defects which originated in dried garlic used in the production process. Samples of garlic (n = 26) were examinated using standard cultural methods (counts of fungi, lactic acid bacteria-LAB, spore-producing Bacillus sp. and the presence of anaerobic saccharolytic and proteolytic clostridia), automated system TEMPO (total viable count, Enterobacteriaceae), immunoenzymatic method using VIDAS tests (occurrence of Salmonella sp. and Listeria monocytogenes). The number of total viable count was ranged from 3.51 to 6.85 log CFU/g. Enterobacteriaceae were detected only in one sample. Comparably low values were recorded for fungi (1.30 to 3.47 log CFU/g). The number of LAB was ranged from 2.34 to 5.49 log CFU/g. Clostridium sp. were detected in 22 samples. Salmonella sp. and Listeria monocytogenes were not detected. It was found that garlic, regardless of th preservation procedure, might be a source of contamination of garlic mayonnaise sauce especially with lactic acid bacteria and Clostridium sp. spores.

Prevalence of Bacillus cereus in food products in Poland.

INTRODUCTION AND OBJECTIVE: Bacillus cereus is a foodborne pathogen causing two main types of gastrointestinal diseases: emetic and diarrheal. The aim of this study was to investigate the prevalence of the Bacillus cereus group in ready-to-eat (RTE) food products available in retail in Poland. MATERIAL AND METHODS: Samples were collected by Sanitary and Epidemiological Stations within the framework of the national official control and monitoring sampling programme in Poland. In 2016-2020, a total of 45,358 food samples, such as: 'confectionery products and products with cream', as well as 'cereal grains and cereal and flour products', 'milk and milk products', 'sugar and others', 'meat offal and meat products', 'poultry offal and poultry products', 'eggs and egg products', 'fish, seafood and their preserves', 'vegetables' (including legumes), 'coffee, tea, cocoa, fruit, and herbal teas', 'delicatessen and culinary products', and 'foods for particular nutritional uses' were collected. RESULTS: The presence of the presumptive B. cereus group was monitored mainly in two categories of food products: 'confectionery products and products with uncooked cream' and 'confectionery products and products with heat-treated cream'. The number of samples disqualified due to presumptive B. cereus was 339 (0.75%). CONCLUSIONS: This study provides useful information regarding the contamination of RTE products with the B. cereus group, which may have implications for food safety.

A multicenter genomic epidemiological investigation in Brazil, Chile, and Mexico reveals the diversity and persistence of Salmonella populations in surface waters.

This study examined the diversity and persistence of Salmonella in the surface waters of agricultural regions of Brazil, Chile, and Mexico. Research groups (three in 2019-2020 and five in 2021-2022) conducted a long-term survey of surface water across 5-8 months annually (n = 30 monthly). On-site, each team filtered 10-L water samples with modified Moore Swabs to capture Salmonella, which were then isolated and identified using conventional microbiological techniques. Salmonella isolates were sequenced on Illumina platforms. Salmonella was present in 1,493/3,291 water samples (45.8%), with varying isolation rates across countries and years. Newport, Infantis, and Typhimurium were the most frequent among the 128 different serovars. Notably, 22 serovars were found in all three countries, representing almost half of the 1,911 different isolates collected. The resistome comprised 72 antimicrobial resistance (AMR) genes and six point mutations in three genes. At least one AMR determinant was observed in 33.8% (646/1,911) of the isolates, of which 47.4% (306/646) were potentially multidrug resistant. Phylogeny based on core genome multilocus sequence typing (cgMLST) showed that most isolates clustered according to sequence type and country of origin. Only 14 cgMLST multi-country clusters were detected among the 275 clusters. However, further analysis confirmed that close genetic relatedness occurred mostly among isolates from the same country, with three exceptions. Interestingly, isolates closely related phylogenetically were recovered over multiple years within the same country, indicating the persistence of certain Salmonella in those areas. In conclusion, surface waters in these regions are consistently contaminated with diverse Salmonella, including strains that persist over time.IMPORTANCESalmonella is a leading foodborne pathogen responsible for millions of illnesses, hospitalizations, and deaths annually. Although Salmonella-contaminated water has now been recognized as an important contamination source in the agrifood chain, there is a lack of knowledge on the global occurrence and diversity of Salmonella in surface water. Moreover, there has been insufficient research on Salmonella in surface waters from Latin American countries that are major producers and exporters of agricultural products. Incorporating genetic profiling of Salmonella isolates from underrepresented regions, such as Latin America, enhances our understanding of the pathogen's ecology, evolution, antimicrobial resistance, and pathogenicity. Moreover, leveraging genomic data derived from pathogens isolated from diverse geographical areas is critical for assessing the potential public health risk posed by the pathogen and expediting investigations of foodborne outbreaks. Ultimately, global efforts contribute significantly to reducing the incidence of foodborne infections.

Application of antimicrobial chitosan-Furcellaran-hydrolysate gelatin edible coatings enriched with bioactive peptides in shelf-life extension of pork loin stored at 4 and -20 °C.

In this study, the authors investigate the preservative capabilities of edible coatings comprising a blend of chitosan, furcellaran and gelatin hydrolysate enhanced with the bioactive peptides RW4 and LL37. The preservative effects on pork samples stored for 21 days at 4 °C and 6 months at -20 °C were studied, while examining changes in microbiological contamination, pH levels, water activity and sensory attributes. Microbiological analyses reveal the coatings' antimicrobial efficacy against aerobic bacteria, microscopic fungi and yeasts, particularly during the initial storage period, when coated samples exhibit microbial reductions of 0.5-2 log CFU/g compared to the controls. The coatings have no discernible impact on water activity during storage in refrigerated or freezer conditions. Notably, differences in pH development can be observed between the coated and control samples, potentially attributable to the antimicrobial action of the coatings. Sensory analysis allows to highlight the inhibition of deterioration related to sensory attributes through the use of edible coatings. In conclusion, employing bioactive peptide-enriched edible coatings holds promise for extending the shelf-life of perishable foods.

Enhancing Surgical Safety: Microbiological Air Control in Operating Theatres at University Medical Centre Maribor.

BACKGROUND: the aim of the study was to assess microbiological air quality in operating theatres by determining the level of microbiological contamination of the air and critical surfaces using the passive air sampling method and compliance of the operating theatre staff with infection control measures. MATERIALS AND METHODS: The prospective study was conducted in the surgical block of the University Medical Centre Maribor. For two months continuously, ten operating theatres were assessed for microbial contamination of air and surfaces during quiet and active times of the day. A passive air sampling method with Petri dishes on an agar specially adapted for this purpose (plate count agar) was used. In addition, ten surgical procedures were observed to assess staff compliance with recommended practises. RESULTS: Air samples met microbiological standards in all operating theatres. In both sampling sessions of the day (quiet and active periods), microbial contamination of the air was always within the limit of 10 CFU/m3. The average number of bacterial colonies was zero to two during quiet phases and one to four during active phases. Approximately 60% of the isolates from the operating theatres belonged mainly to the genus Staphylococcus: S. epidermidis (36% of the isolates), S. hominis (17.5%) and S. haemolyticus (5.5%). The rest were identified as Streptococcus anginosus (23%) and Bacillus sp. (18%). Pathogenic bacteria and moulds were not present. In regard to staff compliance with good surgical practise, the former varied by behaviour and function, with non-compliance in pre-operative skin preparation and operating theatre congestion being notable. The cleanliness of the environment was satisfactory. CONCLUSIONS: Microbiological air control is extremely important for the safety and success of both surgical and postoperative practises. In spite of good results obtained in the study, further improvements in surgical staff compliance with good surgical practise are essential to reduce surgical site infections.

Assessment of quality and safety aspects of homemade and commercial baby foods.

Dietary Guidelines in some countries recommend avoiding commercially processed baby food, while others encourage the consultation of ingredients and nutritional information. Therefore, the objective of this study was to systematically analyze different baby foods obtained from commercial market and "homemade" produced, in order to verify whether comercial products have low nutritional and unsafety attributes. The samples were analyzed for chemical composition, physicochemical aspects, texture, microbiological and mycotoxin contamination, and pesticide residues. Results showed that, in general, commercial samples have a higher energy density and better ratio of macronutrients. The sodium, pH, and texture of both products were in accordance with the recommendations. None of the baby foods evaluated were contaminated with yeast and molds, total coliforms, or Escherichia coli; however, Salmonella sp. was confirmed in one homemade sample. Pesticide residues were detected in all analyzed baby food samples; however, at lower levels than the limit of quantification. Ochratoxin A was detected in one homemade baby food sample (5.76 µg /kg). Considering the samples evaluated, commercial baby food samples appeared to be safer in relation to microbiological, pesticide residue standards, and mycotoxin contamination. Therefore, it could be concluded that the quality of commercial and homemade baby foods still needs to be improved, as well as more studies related to a critical analyses of both types of processes used.