Aerobic Colony Counts Research Articles

Environmental bacterial and fungal contamination in high touch surfaces and indoor air of a paediatric intensive care unit in Maputo Central Hospital, Mozambique in 2018

SummaryBackgroundThe hospital environment serves as a reservoir of microorganisms which may be associated with healthcare-associated infections (HCAI). The study of environmental contamination with microorganisms is a method for the assessment of hospital environmental hygiene. We sought to evaluate the environmental colonisation of a national reference hospital unit, using the total aerobic colony count (ACC) and the isolated microorganisms, as assessment tools.MethodsA cross-sectional study was conducted in the Paediatric Intensive Care Unit (PICU) of the Hospital Central de Maputo during a four-week period in 2018. Surfaces and air were sampled before and after room cleaning, using swabs and passive air method. Those samples were processed at the microbiology laboratory where total ACC levels were evaluated, and microorganisms were isolated, identified and assessed for antibiotic susceptibility.DiscussionComparison of the total median ACC of the indoor air (287 cfu/m3 before and 195 cfu/m3 after) and surfaces (0.38 cfu/cm2 before and 0.33 cfu/cm2 after) before and after room cleaning did not show significant differences (P>0.05). Microorganisms of epidemiological importance, including coagulase negative staphylococci (CoNS), Klebsiella pneumoniae and Serratia odorifera were isolated and all of these three were multi-drug resistant (MDR).ConclusionThe results showed controlled contamination levels on high touch surfaces in the patient environment and a high level of contamination of the indoor air suggesting deficiencies in the PICU environmental decontamination process. There was evidence of the presence of fungi and MDR species of epidemiological importance in the context of HCAI.

From Nutritional Adequacy to Hygiene Quality: A Detailed Assessment of Commercial Raw Pet-Food for Dogs and Cats.

Simple SummaryAs alternative diets to processed pet food, raw meat-based diets (RMBDs) have received increasing attention in recent years. Commercial RMBDs consist mainly of raw meats, animal by-products, such as offal, and bones. Most RMBDs do not contain additives; therefore, they potentially pose a risk of nutritional imbalances to adults and, to a greater extent, growing animals. RMBDs are frozen ready-to-use products that are fed to pets after being thawed. Bacterial contamination of RMBDs is an area of concern, including the risk of spreading zoonotic diseases to humans. In this study, a detailed assessment of commercial RMBDs was performed in relation to nutritional adequacy and hygiene quality. The results showed that the tested products often provided deficient amounts of essential nutrients, were nutritionally unbalanced, and very rich in fat. They were also characterized by high microbial contamination, showing low hygiene quality. This study provides information that indicates the need for strict monitoring of the nutritional and microbiological quality of commercial RMBDs.Raw meat-based diets (RMBDs) are widely used as unconventional diets for dogs and cats at different life stages, despite concerns regarding nutritional adequacy and microbial contamination. The aim of this study was to evaluate both the nutritional and hygiene quality profile of RMBDs purchased in Germany. For this purpose, crude nutrients were assessed in 44 RMBDs and compared to declared values. In addition, selected minerals were determined in 31 RMBDs labelled as complete and compared to the minimum requirement (MR) for intended species and life stages. Aerobic colony count (ACC) and Enterobacteriaceae were used to assess the hygiene quality of 37 commercial RMBDs, while the presence of Salmonella spp. was examined in 10 products. Fat and protein content exceeded tolerated deviation from declared values in 33% and 45% of RMBDs, respectively. Each RMBD showed at least one concern regarding nutrient content. The RMBDs had high fat contents (mean 69, range 33–95 g/Mcal) that were negatively correlated with protein (r = −0.74, p < 0.0001). Considerable contaminations by ACC and Enterobacteriaceae were found (2.61 × 108 ± 3.63 × 108 and 3.61 × 106 ± 8.39 x106 CFU/g, respectively). A higher count of Enterobacteriaceae was detected in a frozen RMBDs made of poultry or carcasses from different animals, compared to the thawed counterpart (p = 0.003), as well as compared to other sources, such as beef, horse, and lamb, regardless of the storage condition. Salmonella spp. were found in 2/10 RMBDs. This study confirmed that feeding commercial RMBDs might pose a risk to pet health.

Assessing decontamination practices at a medical microbiology research laboratory

To our knowledge, this is the first study to conduct an objective assessment of the routine decontamination practices at a medical microbiology research laboratory (MRL) a year after a biosafety training was provided to all laboratory staff. Between March 28th and June 28th, 2021, unobtrusive observations were carried out to identify-three high-touch surfaces at the MRL during different working hours. Swabbing was used to evaluate the effectiveness of the disinfectant used in the laboratory. All three high-touch surfaces were sampled before and after decontamination with 200 ppm of 5 % sodium hypochlorite (household bleach) to quantify the microbial load and identify the types of organisms residing on the laboratory surfaces. A higher concentration (500 ppm) of 5 % sodium hypochlorite was employed after refresher training was provided to housekeeping staff, and resampling of the three surfaces was carried out during a 4-week follow-up period using the same procedure. The three high-touch surfaces identified were the two sides of the workbench (22 %–24 %) and the front surface of one incubator (14 %). Anthracoid bacilli and Staphylococcus aureus were the most commonly found organisms on laboratory surfaces pre-intervention (100 % and 89 %, respectively) and post-intervention (56 % and 44 %, respectively). Other microorganisms detected included Salmonella spp. (27.7 %), Proteus spp. (5.6 %), Escherichia coli (5.6 %), and Klebsiella spp. (33.3 %). Employing a higher concentration (500 ppm) of sodium hypochlorite significantly (p ≤ 0.000) reduced the total aerobic colony count from an average of 15–250 cfu/cm2 to 10–60 cfu/cm2. This study demonstrated suboptimal decontamination practices at the MRL and the need to apply a higher concentration (500 ppm) of sodium hypochlorite to reduce the overall microbial load. It also demonstrated the importance of quantitative assessment to monitor decontamination practices and ensure staff compliance. More studies are needed to identify bacterial communities within the laboratory, which will help provide guidance regarding the types, proper concentrations, and appropriateness of the in -use disinfectants. Furthermore, large-scale studies on the acceptable level of residual contamination following any decontamination process are urgently recommended.

Bacteriological Survey of Fresh Minced Beef on Sale at Retail Outlets in Scotland in 2019: Three Foodborne Pathogens, Hygiene Process Indicators, and Phenotypic Antimicrobial Resistance

The health and economic burden of foodborne illness is high, with approximately 2.4 million cases occurring annually in the United Kingdom. A survey to understand the baseline microbial quality and prevalence of food-related hazards of fresh beef mince on retail sale could inform risk assessment, management, and communication to ensure the safety of this commodity. In such a survey, a two-stage sampling design was used to reflect variations in population density and the market share of five categories of retail outlets in Scotland. From January to December 2019, 1,009 fresh minced beef samples were collected from 15 geographic areas. The microbial quality of each sample was assessed using aerobic colony count and Escherichia coli count. Samples were cultured for Campylobacter and Salmonella, and PCR was used to detect target genes (stx1 all variants, stx2 a to g, and rfbO157) for Shiga toxin-producing E. coli (STEC). The presence of viable E. coli O157 and STEC in samples with a positive PCR signal was confirmed via culture and isolation. Phenotypic antimicrobial sensitivity patterns of cultured pathogens and 100 E. coli isolates were determined, mostly via disk diffusion. The median aerobic colony count and E. coli counts were 6.4 × 105 (interquartile range, 6.9 × 104 to 9.6 × 106) and <10 CFU/g (interquartile range, <10 to 10) of minced beef, respectively. The prevalence was 0.1% (95% confidence interval [CI], 0 to 0.7%) for Campylobacter, 0.3% (95% CI, 0 to 1%) for Salmonella, 22% (95% CI, 20 to 25%) for PCR-positive STEC, and 4% (95% CI, 2 to 5%) for culture-positive STEC. The evidence for phenotypic antimicrobial resistance detected did not give cause for concern, mainly occurring in a few E. coli isolates as single nonsusceptibilities to first-line active substances. The low prevalence of pathogens and phenotypic antimicrobial resistance is encouraging, but ongoing consumer food safety education is necessary to mitigate the residual public health risk.

Microbiological Safety of Toasted Ukwa (African Breadfruit) Snack Sold in Aba, South-Eastern Nigeria

A microbiological assay was conducted to assess consumer safety of toasted ukwa (African breadfruit) snack in the Aba metropolis, South-eastern Nigeria. The microbial loads, isolation and identification were carried out by the spread plate agar dilution method. Results indicated that the counts of bacteria ranged from 3.12-7.22x103cfu/g. The fungal counts ranged from 2.11- 5.48x103cfu/g while coliforms were detected in some of the market samples with values ranging from 0.00-0.16x103cfu/g. Staphylococcus aureus, Bacillus spp., Streptococcus spp Klebsiella spp. were bacteria isolated from the samples. Aspergillus niger, Fusarium spp., Mucor spp. and Aspergillus flavus were the isolated fungi. No Escherichia coli or other significant pathogens produced by food were identified from the samples. Coliform (Aerobic colony counts) were lower than the International Food Standards (≥ 105cfu/g) and the absence of microbial food-borne pathogens makes these ukwa samples safe for consumption.

The effects of different packaging methods and sous vide cooking on chemical, sensory, and microbiological changes of marinated crayfish ( Astacus leptodactylus Esch., 1823)

Chemical, sensory parameters and microbiological condition of marinated crayfish (Astacus leptodactylus), with emphasis on the quality and safety parameters in brine, vacuum packaging (VP) and sous-vide cooking were investigated. Quality assessment of crayfish stored in in brine, vacuum packaging (VP) and sous-vide (SV) for up to 120 days at 4±1 °C was done by the monitoring of sensory, microbiological, pH value, total volatile basic nitrogen (TVB-N), thiobarbituric acid (TBA) and peroxide value (PV). The highest concentration of TVB-N was recorded in the marinated crayfish stored under brine whereas the lowest TVB-N in the marinated crayfish stored under SV packed conditions. The concentration of TBA increased and its level reached over 5.44 mg MA/kg for crayfish stored in brine, 3.57 mg MA/kg for VP and 2.54 mg MA/kg for SV at 120 days. The formation of PV increased with the time of storage and was the lowest in the marinated crayfish stored in SV packed. During storage period, aerobic and anaerobic colony count, Escherichia coli, Coagulase positive staphylococcus, Listeria monocytogenes, Salmonella, and Clostridium perfringens were not found in any of samples. The marinated crayfish packed in sous-vide had extended shelf life at 4±1 °C compared to that packaged in brine and VP according to physico-chemical analysis.

Systematic Review and Meta-Analysis of the Efficacy of Interventions Applied during Primary Processing to Reduce Microbial Contamination on Pig Carcasses.

Interventions from lairage to the chilling stage of the pig slaughter process are important to reduce microbial contamination of carcasses. The aim of this systematic review and meta-analysis was to assess the effectiveness of abattoir interventions in reducing aerobic colony count (ACC), Enterobacteriaceae, generic Escherichia coli, and Yersinia spp. on pig carcasses. The database searches spanned a 30 year period from 1990 to 2021. Following a structured, predefined protocol, 22 articles, which were judged as having a low risk of bias, were used for detailed data extraction and meta-analysis. The meta-analysis included data on lairage interventions for live pigs, standard processing procedures for pig carcasses, prechilling interventions, multiple carcass interventions, and carcass chilling. Risk ratios (RRs) for prevalence studies and mean log differences (MDs) for concentration outcomes were calculated using random effects models. The meta-analysis found that scalding under commercial abattoir conditions effectively reduced the prevalence of Enterobacteriaceae (RR: 0.05, 95% CI: 0.02 to 0.12, I2 = 87%) and ACC (MD: −2.84, 95% CI: −3.50 to −2.18, I2 = 99%) on pig carcasses. Similarly, significant reductions of these two groups of bacteria on carcasses were also found after singeing (RR: 0.25, 95% CI: 0.14 to 0.44, I2 = 90% and MD: −1.95, 95% CI: −2.40 to −1.50, I2 = 96%, respectively). Rectum sealing effectively reduces the prevalence of Y. enterocolitica on pig carcasses (RR: 0.60, 95% CI: 0.41 to 0.89, I2 = 0%). Under commercial abattoir conditions, hot water washing significantly reduced ACC (MD: −1.32, 95% CI: −1.93 to −0.71, I2 = 93%) and generic E. coli counts (MD: −1.23, 95% CI: −1.89 to −0.57, I2 = 61%) on pig carcasses. Conventional dry chilling reduced Enterobacteriaceae prevalence on pig carcasses (RR: 0.32, 95% CI: 0.21 to 0.48, I2 = 81%). Multiple carcass interventions significantly reduced Enterobacteriaceae prevalence (RR: 0.11, 95% CI: 0.05 to 0.23, I2 = 94%) and ACC on carcasses (MD: −2.85, 95% CI: −3.33 to −2.37, I2 = 97%). The results clearly show that standard processing procedures of scalding and singeing and the hazard-based intervention of hot water washing are effective in reducing indicator bacteria on pig carcasses. The prevalence of Y. enterocolitica on pig carcasses was effectively reduced by the standard procedure of rectum sealing; nevertheless, this was the only intervention for Yersinia investigated under commercial conditions. High heterogeneity among studies and trials investigating interventions and overall lack of large, controlled trials conducted under commercial conditions suggest that more in-depth research is needed.

Longitudinal Assessment of Contamination Patterns on Workstations on Wheels (WOWs)

Background Representations of contamination on portable medical equipment inform strategies to prevent transmission and healthcare-associated infections (HAIs). While periodic disinfection of equipment is required in most hospitals, the complexity of demands on staff may limit their ability to adequately disinfect multiple surfaces and touch points on a piece of equipment. The purpose of this study was to determine if current disinfection practices were effectively managing bioburden on WOWs on our hospital wards. Methods Samples were collected using press plate for four weeks from 10 WOWs on three medical-surgical units in our hospital. The sampling scheme limited the ability of staff to anticipate sampling and ensured multiple surfaces on each WOW were consistently sampled. Aerobic bacterial colony counts were calculated after 24 hours of incubation. Bayesian multilevel models estimated the mean bioburden and compared bioburden from different locations on WOWs. Results Out of the 452 samples, the estimated mean colony count (95% credible interval) was 29.2 (16.1-51.1). The incident risk-ratio comparing the handle to the other surfaces on the WOWs were 0.43 (0.32-0.55) for the keyboard, 0.29 (0.22-0.38) for the tray, and 0.22 (0.16-0.29) for the mouse. Conclusions The handle used for moving the WOW around, had greater bioburden compared to the keyboard, tray, or the mouse. Difference in the bioburden may reflect number of touches and lack of hand hygiene when moving equipment. The lower bioburden on keyboards and mouses may conversely reflect greater attention to hand hygiene or may be an artifact of sampling (less contact with press plates). The correlation of bioburden to HAI transmission was not studied here so the significance of bioburden alone in the absence of HAI monitoring is uncertain. Representations of contamination on portable medical equipment inform strategies to prevent transmission and healthcare-associated infections (HAIs). While periodic disinfection of equipment is required in most hospitals, the complexity of demands on staff may limit their ability to adequately disinfect multiple surfaces and touch points on a piece of equipment. The purpose of this study was to determine if current disinfection practices were effectively managing bioburden on WOWs on our hospital wards. Samples were collected using press plate for four weeks from 10 WOWs on three medical-surgical units in our hospital. The sampling scheme limited the ability of staff to anticipate sampling and ensured multiple surfaces on each WOW were consistently sampled. Aerobic bacterial colony counts were calculated after 24 hours of incubation. Bayesian multilevel models estimated the mean bioburden and compared bioburden from different locations on WOWs. Out of the 452 samples, the estimated mean colony count (95% credible interval) was 29.2 (16.1-51.1). The incident risk-ratio comparing the handle to the other surfaces on the WOWs were 0.43 (0.32-0.55) for the keyboard, 0.29 (0.22-0.38) for the tray, and 0.22 (0.16-0.29) for the mouse. The handle used for moving the WOW around, had greater bioburden compared to the keyboard, tray, or the mouse. Difference in the bioburden may reflect number of touches and lack of hand hygiene when moving equipment. The lower bioburden on keyboards and mouses may conversely reflect greater attention to hand hygiene or may be an artifact of sampling (less contact with press plates). The correlation of bioburden to HAI transmission was not studied here so the significance of bioburden alone in the absence of HAI monitoring is uncertain.

A Better Disinfectant for Low-Resourced Hospitals? A Multi-Period Cluster Randomised Trial Comparing Hypochlorous Acid with Sodium Hypochlorite in Nigerian Hospitals: The EWASH Trial.

Environmental hygiene in hospitals is a major challenge worldwide. Low-resourced hospitals in African countries continue to rely on sodium hypochlorite (NaOCl) as major disinfectant. However, NaOCl has several limitations such as the need for daily dilution, irritation, and corrosion. Hypochlorous acid (HOCl) is an innovative surface disinfectant produced by saline electrolysis with a much higher safety profile. We assessed non-inferiority of HOCl against standard NaOCl for surface disinfection in two hospitals in Abuja, Nigeria using a double-blind multi-period randomised cross-over study. Microbiological cleanliness [Aerobic Colony Counts (ACC)] was measured using dipslides. We aggregated data at the cluster-period level and fitted a linear regression. Microbiological cleanliness was high for both disinfectant (84.8% HOCl; 87.3% NaOCl). No evidence of a significant difference between the two products was found (RD = 2%, 90%CI: −5.1%–+0.4%; p-value = 0.163). We cannot rule out the possibility of HOCl being inferior by up to 5.1 percentage points and hence we did not strictly meet the non-inferiority margin we set ourselves. However, even a maximum difference of 5.1% in favour of sodium hypochlorite would not suggest there is a clinically relevant difference between the two products. We demonstrated that HOCl and NaOCl have a similar efficacy in achieving microbiological cleanliness, with HOCl acting at a lower concentration. With a better safety profile, and potential applicability across many healthcare uses, HOCl provides an attractive and potentially cost-efficient alternative to sodium hypochlorite in low resource settings.

Application of Gamma Irradiation Treatment on the Physicochemical and Microbiological Quality of an Artisanal Hard Cheese

The objective of this study was to evaluate the efficacy of gamma irradiation, applied to different cheese sample sizes (250g and 500 g), against Listeria monocytogenes, Escherichia coli, coliforms and aerobic colony counts. The effects on cheese physicochemical and odour properties and all costs involved for the treatment were quantified. The Cobalt-60 γ-irradiator was used at a maximum dose of 5.0 kGy. The values for cheese moisture (28.6%), ash (3.78%), pH (5.1), protein (29.6%), fat (30.7%), salt (1.95%) and water activity (0.92%) were within the acceptable ranges for hard cheese after gamma irradiation treatment. The colour (yellowness, redness, chroma and hue angle) and texture (cohesiveness and springiness) values decreased (p &lt; 0.05) with the treatment. Compounds such as safrole, acetylpyrazine, thiophene, 3,5-octadien-2-one and 1-Octen-3-one were present after the treatment, regardless of sample size. The gamma irradiation treatment resulted in 100%, 87.2%, 85.1% and 77.3% reduction in L. monocytogenes, coliforms, E. coli and aerobic colony counts, respectively. The study highlighted the efficacy of irradiation treatment and its affordability for resource-limited producers.

The Impact of Cattle Hide Cleanliness Scores on Microbial Contamination of Carcasses During Slaughtering

Abstract This study aimed to investigate the effects of cleanliness scoring on the microbiological load of hide and the final contamination of cattle carcasses. Fifty cattle were classified from 1 (clean and dry) to 5 (filthy and wet). Aerobic colony count (ACC) and counts of Enterobacteriaceae (EC) and E. coli (ECC) were determined on the brisket, abdominal midline, rump, groin sites of the hides, and brisket, flank, groin, and hock of the carcasses. On hides, ACC ranged from 3.15±0.13 log cfu/cm2 in category 1 to 8.14±0.21 log cfu/cm2 in category 5. EC and ECC were ranging between 1.13±0.07 and 2.80±0.09 log cfu/cm2, and 1.21±0.05 and 2.15±0.07 log cfu/cm2, respectively. While the mean ACC on the carcasses ranged between 2.18±0.07 and 2.63±0.05 log cfu/cm2 irrespective of the categories, Enterobacteriaceae and E. coli could not be counted due to the detection limits. It was concluded that although the level of bacterial load increased significantly (P&lt;0.001) with the increasing cleanliness category on the hide of the animals, the reflection of this increasing trend on carcasses and different parts of the carcasses were inconsistent and the hygiene provided in the slaughterhouse and processing line was the main factor to reduce cross-contamination during processing.

Comparison between adenosine triphosphate bioluminescence and aerobic colony count to assess surface sanitation in the hospital environment

Background: Adenosine triphosphate bioluminescence produced by the firefly luciferase has been successfullyintroduced to verify cleaning procedures in the food industry according to the Hazard Analysis Critical Control Pointprogram.Our aim was to evaluate the reliability of bioluminescence as a tool to monitor the effectiveness of sanitation in healthcaresettings, in comparison with the microbiological gold standard.Methods: 614 surfaces of various material were randomly sampled in Policlinico University Hospital units in Palermo,Italy, to detect adenosine triphosphate bioluminescence and aerobic colony count. Linear regression model andPearson correlation coefficient were used to estimate the relationship between the two variables of the study.Results: Aerobic colony count median was 1.71 colony forming units/cm2 (interquartile range = 3.8), whereasadenosine triphosphate median was 59.9 relative light units/cm2 (interquartile range = 128.3). Pearson coefficientR2 was 0.09. Sensitivity and specificity of bioluminescence test with respect to microbiology were 46% and 71%,whereas positive predictive value and negative predictive value were 53% and 65%, respectively.Conclusion: According to our results, there seemed to be no linear correlation between aerobic colony countand adenosine triphosphate values, suggesting that current bioluminescence technology has not any proportionalrelationships with culturable microbes contaminating environmental surfaces in health-care settings.

Risk categorisation of poultry abattoirs on the basis of the current process hygiene criteria and indicator microorganisms

Risk categorisation of abattoirs based on their hygiene process performances has been suggested as an essential component of a risk-based meat safety assurance system. Two large-scale and two small-scale poultry abattoirs, located in Serbia, were subjects of the study aiming to investigate the usefulness of testing for pathogens and indicator microorganisms for abattoir risk categorisation. Fifty pooled samples of neck skins from chilled broiler carcasses were taken during two sampling days in each abattoir. The samples were tested for aerobic colony count (ACC), Enterobacteriaceae count (EBC), Escherichia coli count (ECC), Campylobacter count and Salmonella presence. Abattoirs were categorised as low, medium or high risk based on criteria set by regulation for pathogens and criteria set by authors for indicator microorganisms considering differences between poultry and red meat carcass processing. The two large abattoirs were categorised as medium risk, while the two small abattoirs were categorised as high risk regarding the three groups of indicator microorganisms. On the other hand, risk categorisation regarding the two pathogens was different − the two large and one of the small abattoirs were categorised as high risk, while the other small abattoir was categorised as low risk. No statistical association between the count of any indicator and Campylobacter count was found. Only a very weak statistical association was found between indicator counts and Salmonella presence on chilled carcasses. The level of indicators on chilled carcasses is mainly related to abattoir process hygiene, while the presence of pathogens on chilled carcasses could be considerably affected by their pre-abattoir status. Therefore, risk categorisation of poultry abattoirs based on ACC, EBC and/or ECC merits further investigation and standardisation. • Poultry abattoirs risk categorisation approaches were assessed. • Chilled broiler carcasses were tested for indicators and pathogens. • Indicators' counts do not reflect pathogens' presence/counts on chilled carcasses. • Indicators reflect abattoir process hygiene better than pathogens. • Pathogens' presence is pre-abattoir rather than abattoir process hygiene dependant.

The beneficial effects of the addition of pulped Agaricus bisporus mushroom body co-product to Kraft pulp packaging materials

The aim of this study is to up-cycle mushroom production waste by incorporating macerated mushroom caps and stalks into moulded Kraft pulp packaging material and to compare the properties of this new material with existing food packaging materials, namely moulded pulp packaging (MPP) and polypropylene (PP) punnets. Corrugated cardboard fibre (CCF) was blended with 30% waste mushroom caps and stalks (MW) with and without addition of alkyl ketene dimer (AKD). Microbiological assessment of the packaging material from selected production stages and the finished punnets was conducted the determine levels of aerobic colony count, Pseudomonas spp., and yeasts and moulds. Also, finished punnets were characterized for their physical properties (moisture, density, surface hydrophobicity, mechanical properties, microstructure) and used for cold storage trials using fresh mushrooms comparing performance to MPP and PP punnets in terms of change in colour (CIE L*, a*, b*) and microbial load of the packed mushrooms. During seven days of cold storage of fresh mushrooms, both mushrooms and packaging materials were analysed for their total aerobic bacteria, Pseudomonas spp., and yeasts and moulds. Results showed that at the end of the storage, MW/CCF and MW/CCF + AKD punnets showed similar performance with PP punnet on the microbial quality of fresh mushroom. The fresh mushrooms had better colour compared with those stored in MPP. The paper-based punnets had higher microbial growth in the packaging material than PP punnet. Incorporation MW improved the mechanical properties of CCF. The MW/CCF and MW/CCF + AKD punnets had a higher Young’s modulus than MPP. Results indicated that, moulded pulp punnets prepared using 30% mushroom waste used for fresh mushroom packaging provide the similar microbial quality with better product colour compared with commercial counterparts while allowing agri-waste up-cycling.

Effect of time and temperature before chilling on the hygiene of carcasses in wild boar hunted in central Italy.

The interest in certified game meat chains highlights the need for the evaluation and the management of factors affecting carcass hygiene along the peculiar steps of the production. The effects of time and temperature before chilling were specifically evaluated on aerobic colony count and Enterobacteriaceae count in hunted wild boar carcasses. Thirty wild boars were considered in two process steps where the hunted animal are still not chilled: after evisceration and just before chilling. Environmental temperature, carcass temperature and the elapse time between the two-step considered were registered. Furthermore, surface microbial loads were analyzed on the inner part of the carcasses. The mean time between the two sampling steps was 6 hours with an average environmental temperature of 20.49°C. A carcass temperature 9.6°C drop was observed during this period. In this lap of time aerobic colony count and Enterobacteriaceae count increased of 0.68 Log CFU/cm2 and 1.01 Log CFU/cm2 respectively, with a moderate correlation with the time but not with the temperature delta. The results reveal that the temperature conditions in central Italy hunting areas were not able to quickly reduce the carcass temperature and therefore the time between carcass evisceration and chilling should not exceed 6 hours.

Hospital cleaning

The aim of this narrative review is to present up-to-date facts concerning hospital cleaning (HC). HC is essential in the prevention of healthcare associated infections (HAI). If a proper HC is followed by a proper use of disinfectants even the HAI caused by the most dangerous nosocomial pathogens like methicillin-resistant Staphylococcus aureus, vancomycin- resistant Enterococcus, carbapenem-resistant Pseudomonas aeruginosa and multidrug-resistant Acinetobacter baumannii may be stopped without closing the ward or placing the patients in isolation. Critical hospital surfaces that may be highly contaminated with pathogens include toilet seats and bowels, toilet flush handles, doorhandles, furniture, hospital equipment, linen, clothes, buttons, switches, computers, printers, shelves, cellphones, curtains, patient chairs, nurse call-buttons and bed rails. Hand-touch sites at bedside pose the highest risk of HAI for patients and these should be targeted with continuous and detail cleaning. The most used methods for the assessment of hospital cleanliness are visual inspection, aerobic colony counts, adenosine triphosphate (ATP) bioluminescence and fluorescent markers. Together with soaps and detergents the environmental-friendly disinfectants like hydrogen peroxide, high-pressure steam, electrolyzed water, ozone, probiotic cleaners and microfiber cloths have a priority in hospital cleaning. Recent advances in the methods of hospital cleaning together with the continuous education of cleaning staff and nurses significantly contribute to the prevention and control of hospital outbreaks.

Whole-genome sequencing analysis of highly prevalent Salmonella serovars in wild boars from a national park in Sardinia

The study investigated Salmonella prevalence in slaughtered wild boars from Asinara island National Park in Sardinia (Italy). Salmonella isolates were serotyped and the antimicrobial resistance profile was evaluated. Isolates were furthermore characterized with Whole Genome Sequencing. Additional analysis were performed in order to evaluate the microbial hygiene of wild boars carcasses. A total of 306 samples were tested for Salmonella presence, of which n. 270 were from n. 90 slaughtered wild boars and n. 36 were from slaughterhouse environment. Salmonella was detected in 32/90 (35.6%) colon content and 16/90 (17.8%) mesenteric lymph nodes samples. The overall prevalence of Salmonella carriers wild boars, either in colon content and/or lymph nodes, was 42/90 (46.7%) but only one animal was found positive at carcass level. Prevalence was not influenced ( P > 0.05) by the age and the gender of the animals. Eight different Salmonella serotypes were identified between 50 isolates, with the most common ones being Abony and Newport. The sequence analysis showed that S. Abony and S. Newport strains clustered separately from public genomes. This finding refects the origin of the animals from the geographical closed environment of Asinara island. Moreover, sequence analysis showed high similarity between strains belonging to the same serovar. S . Derby and S . Agona strains exhibited phenotypic resistance to fosfomycin and harboured the fosA7 gene. The mean aerobic colony count and Enterobacteriaceae values showed a good hygiene level of the carcasses. This study demonstrated that Salmonella enterica is widespread in wild boar population of Asinara island and could play an important role in transmission to humans. The finding of Salmonella strains resistant to fosfomycin is of primary importance as this drug is used as an alternative treatment for infections caused by multi-drug resistant microorganisms. • Salmonella in wild boar play a role in transmission to humans. • High variability of Salmonella serovars. • High similarity of Salmonella serovars with whole genome sequencing. • Extended sensitivity to antimicrobials. • Fosfomycin resistance encoded by the gene fosA 7 in S. Agona and S. Derby isolates.

Microbial burden on environmental surfaces in patient rooms before daily cleaning-Analysis of multiple confounding variables.

Estimated levels of microbial burden on hospital environmental surfaces vary substantially among published studies. Cultures obtained during a cluster-controlled crossover trial of a quaternary ammonium (Quat) disinfectant versus an improved hydrogen peroxide (IHP) disinfectant provided additional data on the amount of microbial burden on selected surfaces. RODAC plates containing D/E neutralizing agar were used to sample a convenience sample of 5-8 high-touch surfaces in patient rooms on 2 medical wards, an intensive care unit, and a step-down unit at a large hospital. Before routine daily cleaning, samples were obtained in varying rooms over an 11-month period. RODAC plates (1 per surface sampled) were incubated for 72 hours, and aerobic colony counts per plate (ACCs) were determined. Statistical analysis was used to determine the potential impact on ACCs of study period, cleaning compliance rate, disinfectant used, ward, surface sampled, and isolation room status. Overall, 590 cultures were obtained on Quat wards and 589 on IHP wards. Multivariable regression analysis revealed that mean ACCs differed significantly by site (P < .001), type of ward (P < .001), isolation room status (P = .039), and study period (P = .036). The highest mean ACCs per RODAC plate were on toilet seats (112.8), bedside rails (92.0), and bathroom grab bars (79.5). The combination of factors analyzed revealed that estimating microbial burden is complex and is affected by multiple factors. Additional studies should evaluate individual sites, ward types, cleaning and disinfection practices, and isolation room status.

The correlation between ATP measurement and microbial contamination of inanimate surfaces

BackgroundThe objective of this study was to determine the correlation between adenosine triphosphate (ATP) measurements and microbial contamination using a standardized method. Secondarily, analyzing reproducibility of ATP measurements and aerobic colony counts (ACC’s) on the same surface.MethodsATP measurements and ACC’s were conducted on 10 pre-defined fomites in a hospital and nursing home setting. Per fomite two ATP measurements and two agar plate measurements were conducted, each measurement was conducted on a 25 cm2 surface. Both measurements were compared and analyzed for correlation.ResultsIn total 200 paired measurements were conducted, 200 ATP measurements and 200 ACC’s. The mean of all ATP measurements tested on the same surface was calculated, as was for all 200 ACC’s. There was a strong correlation between the mean of two ATP measurements on two different sites on the same fomite (R = 0.800, p < 0.001) as well as between two ACC measurements on the same fomite (R = 0.667, p < 0.001). A much weaker correlation was found between RLU values and ACC’s (R = 0.244, p < 0.001).ConclusionsReproducibility of ATP measurements and ACC’s on the same fomite was good. However, the correlation between RLU values and ACC’s on hospital surfaces was much lower. This may be explained by the wide variety of biological material that is measured with ATP, of which the bacterial load is only one of many components. ATP measurement can be used to give a quantifiable outcome for the rating of cleanliness in health care facilities, however the results cannot be translated into the level of microbial contamination.

Microbiological quality aspects of ready-to-eat foods with focus on antibiotic resistance and biofilm formation abilities of foodborne bacteria

AbstractIn this study, microbiological quality of 93 ready-to-eat food products was determined by enumeration of total aerobic bacteria and members of Enterobacteriaceae. Presence of Staphylococcus aureus and Listeria monocytogenes in the products were also investigated. Aerobic colony counts were between 1.9 × 102–3.4 × 108 CFU g−1 for 84.9% and Enterobacteriaceae counts were between 2 × 102 and 6.7 × 106 CFU g−1 for 43% of the samples. S. aureus was detected in 7.5% of the samples, but L. monocytogenes was not detected in any sample. 72.9% of the Enterobacteriaceae isolates showed resistance to at least one antibiotic tested, and 5 among the S. aureus isolates were found to be resistant to penicillin G and 2 against methicillin. Four S. aureus isolates produced only Staphylococcal enterotoxin A and 1 isolate produced both Staphylococcal enterotoxin A and B. Biofilm experiments revealed biofilm formation on polystyrene for 95.8%, 87.5%, and 91.6% of Enterobacteriaceae isolates at 4 °C, 22 °C, and 37 °C, respectively, whereas all S. aureus isolates formed biofilm at all temperatures.