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Background: We examined whether the time to positivity (TTP) and growth and detection plot graph (GDPG) created by the automated blood culture system can be used to determine the bacterial load in bacteremic patients and its potential association correlation with disease severity. Methods: Known bacterial inocula were injected into the blood culture bottles. The GDPGs for the specific inocula were downloaded and plotted. A cohort of 30 consecutive clinical cultures positive for S. aureus and E. coli was identified. Bacterial load was determined by comparing the GDPG with the "standard" curves. Variables associated with disease severity were compared across 3 bacterial load categories (< 100, 100–1000, > 1000 CFU/mL). Results: S. aureus growth was sensitive to the blood volume obtained whereas E. coli growth was less so. A 12-hour delay in sample transfer to the microbiology laboratory resulted in a decrease in TTP by 2–3 h. Mean TTP was 15 and 10 h for S. aureus and E. coli, respectively, which correlates with > 1000 CFU/mL and 500–1000 CFU/ml. For S. aureus, patients with a bacterial load > 100 CFU/mL had a higher mortality rate, (OR for death = 9.7, 95% CI 1.6–59, p = 0.01). Bacterial load > 1000 CFU/mL had an odds ratio of 6.4 (95% CI1.2-35, p = 0.03) to predict an endovascular source. For E. coli bacteremia, we did not find any correlations with disease severity. Conclusion: GDPG retrieved from the automated blood culture system can be used to estimate bacterial load. S.aureus bacterial load, but not E.coli, was associated with clinical outcome. [ABSTRACT FROM AUTHOR]

The tannery industry produces one of the worst contaminants, and unsafe disposal in nearby waterbodies and landfills has become an imminent threat to public health, especially when the resulting multidrug-resistant bacteria and heavy metals enter community settings and animal food chains. In this study, we have collected 10 tannery wastewater (TWW) samples and 10 additional non-tannery wastewater (NTW) samples to compare the chemical oxygen demand (COD), pH, biological oxygen demand (BOD), dissolved oxygen (DO), total dissolved solids (TDS), chromium concentration, bacterial load, and antibiotic resistance profiles. While COD, pH, and chromium concentration data were previously published from our lab, this part of the study uncovers that TWW samples had a significantly higher bacterial load, compared to the non-tannery wastewater samples (5.89 × 104 and 9.38 × 103 cfu/mL, respectively), higher BOD and TDS values, and significantly lower DO values. The results showed that 53.4, 46.7, 40.0, and 40.0% of the TWW isolates were resistant to ceftriaxone, erythromycin, nalidixic acid, and azithromycin, respectively. On the other hand, 20.0, 30.0, 50.0, and 40.0% of the NTW isolates were resistant to the same antibiotics, respectively. These findings suggest that the TWW isolates were more resistant to antibiotics than the NTW isolates. Moreover, the TWW isolates exhibited higher multidrug resistance than the NTW isolates, 33.33, and 20.00%, respectively. Furthermore, spearman correlation analysis depicts that there is a negative correlation between BOD and bacterial load up to a certain level (r = − 0.7749, p = 0.0085). In addition, there is also a consistent negative correlation between COD and bacterial load (r = − 0.7112, p = 0.0252) and TDS and bacterial load (r = − 0.7621, p = 0.0104). These findings suggest that TWW could pose a significant risk to public health and the environment and highlight the importance of proper wastewater treatment in tannery industries. [ABSTRACT FROM AUTHOR]

Objective·To study the differences in the structure and load of hair follicle microbiota in non-lesional areas among patients with moderate-to-severe acne vulgaris and healthy individuals, and to explore the relationship between microorganisms and the severity of acne vulgaris. Method·A cross-sectional study was used. Patients with moderate or severe acne vulgaris (referred to as acne) and healthy volunteers who visited the Department of Dermatology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, from August 2022 to August 2023. 16S rRNA high-throughput sequencing and quantitative real-time polymerase chain reaction (qPCR) were performed on the follicular contents from the non-lesional areas of the faces of patients with moderate or severe acne and healthy volunteers to analyze the diversity, species composition, and microbial load differences in hair follicle bacteria in patients with different severity of acne. Results·Ten patients with moderate acne, eleven patients with severe acne, and eleven healthy volunteers were included. There were no statistically differences in general data such as age and gender ratio among the three groups. Bacterial α-diversity was significantly lower in both the moderate and severe acne groups compared to the healthy group (P=0.020, P=0.013). The principal coordinates analysis (PCoA) plot showed that the sample distribution of the healthy group was relatively concentrated, with small differences within the group, and the distribution of samples in the moderate and severe acne groups exhibited a certain trend but was relatively scattered, with differences between the groups. There were differences in the trend distribution of the three sample groups, and there were differences in the microbial community structure between the groups. The results of similarity analysis showed significant differences in β-diversity and low similarity in species composition between the healthy and moderate acne groups (P=0.027) and between the healthy and severe acne groups (P=0.017), and high species similarity between the moderate acne and severe acne groups (P=0.160). The dominant bacterial groups at the phylum level were Actinobacteria, Firmicutes, Proteobacteria, and Bacteroidetes. At the genus level, the dominant bacteria in the healthy group were Propionibacterium and unclassified Actinomycetales, and the dominant bacteria in both acne groups were Staphylococcus and Propionibacterium. Compared to the healthy group, the relative abundance of Staphylococcus species in the hair follicles in nonlesional areas of the moderate and severe acne groups was significantly increased (P=0.010, P=0.019). Compared with the healthy control group, the hair follicle microbiota load in non-lesional areas of both the moderate and severe acne groups was significantly increased (both P=0.001). Compared with the moderate acne group, the bacterial load in the hair follicle samples of the severe acne group was significantly increased (P=0.017). Conclusion·The microbial community structure of hair follicles in non-lesional areas of patients with moderate or severe acne is different from that of healthy individuals, and the microbial diversity in the acne group is significantly reduced. The relative abundance of Staphylococcus species in the hair follicles in non-lesional areas of the moderate or severe acne groups is significantly increased compared to the healthy group. As the severity of acne increases, the bacterial load in hair follicles in non-lesional areas significantly increases. This research suggests that the occurrence and severity of acne may be related to the community structure and load of hair follicle microbiota. [ABSTRACT FROM AUTHOR]

Abstract The aim of this study was to quantify the number of non-airborne bacteria that can passively penetrate the layers of four mask types (surgical mask, community face mask type 1 (CFM1), biocidal CFM1 and CFM2) and to determine the influence of wearing conditions for the surgical type. A mask wearer simulator consisting of a 3D anatomical replica of the upper airway connected to a breathing pump was used. Wearing time, filtration quality of the mask, fit (loose vs. tight) and breathing parameters (tidal volume, respiratory rate) were tested. A Staphylococcus epidermidis inoculum was applied to the inner layer. After the wearing simulation, the layers were separated and the bacteria counted. After four hours, no or only a few bacteria were present in the middle and outer layers. Most remained in the inner layer. Surgical mask and CFM1 retained more bacteria and provided a breeding ground for germs. The biocidal CFM1 rapidly reduced the number in the inner layer. The breathing parameters had no influence, in contrast to fit and wearing time. These results confirm that the standard test for bacterial filtration efficiency, which includes the active penetration of airborne bacteria into aerosol droplets, is the most objective measure of the ability of bacteria to penetrate through the mask layers, as the passive penetration ability of non-airborne bacteria is insignificant.

Objective·To study the differences in the structure and load of hair follicle microbiota in non-lesional areas among patients with moderate-to-severe acne vulgaris and healthy individuals, and to explore the relationship between microorganisms and the severity of acne vulgaris.Method·A cross-sectional study was used. Patients with moderate or severe acne vulgaris (referred to as acne) and healthy volunteers who visited the Department of Dermatology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, from August 2022 to August 2023. 16S rRNA high-throughput sequencing and quantitative real-time polymerase chain reaction (qPCR) were performed on the follicular contents from the non-lesional areas of the faces of patients with moderate or severe acne and healthy volunteers to analyze the diversity, species composition, and microbial load differences in hair follicle bacteria in patients with different severity of acne.Results·Ten patients with moderate acne, eleven patients with severe acne, and eleven healthy volunteers were included. There were no statistically differences in general data such as age and gender ratio among the three groups. Bacterial α-diversity was significantly lower in both the moderate and severe acne groups compared to the healthy group (P=0.020, P=0.013). The principal coordinates analysis (PCoA) plot showed that the sample distribution of the healthy group was relatively concentrated, with small differences within the group, and the distribution of samples in the moderate and severe acne groups exhibited a certain trend but was relatively scattered, with differences between the groups. There were differences in the trend distribution of the three sample groups, and there were differences in the microbial community structure between the groups. The results of similarity analysis showed significant differences in β-diversity and low similarity in species composition between the healthy and moderate acne groups (P=0.027) and between the healthy and severe acne groups (P=0.017), and high species similarity between the moderate acne and severe acne groups (P=0.160). The dominant bacterial groups at the phylum level were Actinobacteria, Firmicutes, Proteobacteria, and Bacteroidetes. At the genus level, the dominant bacteria in the healthy group were Propionibacterium and unclassified Actinomycetales, and the dominant bacteria in both acne groups were Staphylococcus and Propionibacterium. Compared to the healthy group, the relative abundance of Staphylococcus species in the hair follicles in non-lesional areas of the moderate and severe acne groups was significantly increased (P=0.010, P=0.019). Compared with the healthy control group, the hair follicle microbiota load in non-lesional areas of both the moderate and severe acne groups was significantly increased (both P=0.001). Compared with the moderate acne group, the bacterial load in the hair follicle samples of the severe acne group was significantly increased (P=0.017).Conclusion·The microbial community structure of hair follicles in non-lesional areas of patients with moderate or severe acne is different from that of healthy individuals, and the microbial diversity in the acne group is significantly reduced. The relative abundance of Staphylococcus species in the hair follicles in non-lesional areas of the moderate or severe acne groups is significantly increased compared to the healthy group. As the severity of acne increases, the bacterial load in hair follicles in non-lesional areas significantly increases. This research suggests that the occurrence and severity of acne may be related to the community structure and load of hair follicle microbiota.

Abstract The tannery industry produces one of the worst contaminants, and unsafe disposal in nearby waterbodies and landfills has become an imminent threat to public health, especially when the resulting multidrug-resistant bacteria and heavy metals enter community settings and animal food chains. In this study, we have collected 10 tannery wastewater (TWW) samples and 10 additional non-tannery wastewater (NTW) samples to compare the chemical oxygen demand (COD), pH, biological oxygen demand (BOD), dissolved oxygen (DO), total dissolved solids (TDS), chromium concentration, bacterial load, and antibiotic resistance profiles. While COD, pH, and chromium concentration data were previously published from our lab, this part of the study uncovers that TWW samples had a significantly higher bacterial load, compared to the non-tannery wastewater samples (5.89 × 104 and 9.38 × 103 cfu/mL, respectively), higher BOD and TDS values, and significantly lower DO values. The results showed that 53.4, 46.7, 40.0, and 40.0% of the TWW isolates were resistant to ceftriaxone, erythromycin, nalidixic acid, and azithromycin, respectively. On the other hand, 20.0, 30.0, 50.0, and 40.0% of the NTW isolates were resistant to the same antibiotics, respectively. These findings suggest that the TWW isolates were more resistant to antibiotics than the NTW isolates. Moreover, the TWW isolates exhibited higher multidrug resistance than the NTW isolates, 33.33, and 20.00%, respectively. Furthermore, spearman correlation analysis depicts that there is a negative correlation between BOD and bacterial load up to a certain level (r = − 0.7749, p = 0.0085). In addition, there is also a consistent negative correlation between COD and bacterial load (r = − 0.7112, p = 0.0252) and TDS and bacterial load (r = − 0.7621, p = 0.0104). These findings suggest that TWW could pose a significant risk to public health and the environment and highlight the importance of proper wastewater treatment in tannery industries.

Statement of the Problem: Antimicrobial photodynamic therapy (aPDT) is a protocol proposed for reduction of bacterial load in deep dentin caries in primary and permanent dentitions. However, considering the difference in the morphology of dentinal tubules in primary and permanent teeth, the effect of this treatment may be different on the two dentition types. Purpose: This systematic review and meta-analysis aimed to assess the effect of type of dentition as a determinant of microbial load reduction by aPDT in deep dentin caries. Materials and Method: An electronic search was conducted in Scopus, Web of Science, Cochrane, Medline, and Embase databases, from the first record until April 30, 2022. After article screening by three reviewers, seven studies were included in this meta-analysis. The mean log of Streptococcus mutans (S. mutans) count, Lactobacillus spp. count, and the entire bacteria in the cavity before and after aPDT was calculated with 95% confidence interval (CI), and compared between the two groups of primary and permanent teeth by the random effect model. The I² test was applied to assess the heterogeneity of the findings. Publication bias was evaluated by visual examination of the funnel-plot symmetry. Results: Of 7 retrieved articles, analysis of 3 studies on permanent teeth showed that aPDT caused a significant reduction in total bacterial count in the cavity [SMD: 0.64, 95% CI:(0.31, 0.96), p= 0.0001), S. mutans count [SMD: 0.92, 95% CI:(0.58, 1.25), p< 0.0001], and Lactobacillus spp. [SMD:1.1, 95% CI:(0.76, 1.45), p< 0.00001)]. Analysis of the remaining 4 studies on primary teeth indicated that aPDT had a significant effect only on S. mutans count [SMD: 0.60, 95% CI:(0.23, 0.97), p= 0.001), and its effect on total bacterial count of the cavity [SMD: 0. 90, 95% CI:(-0.02, 1.82), p= 0.05] and Lactobacillus spp. [SMD: 0.18, 95% CI:(-0. 29, 0.64), p= 0.45)] was not significant. Conclusion: The results showed that aPDT could serve as an effective adjunct for reduction of microbial load in permanent teeth. [ABSTRACT FROM AUTHOR]

Abstract In Chile, Piscirickettsia salmonis contains two genetically isolated genogroups, LF-89 and EM-90. However, the impact of a potential co-infection with these two variants on Salmonid Rickettsial Septicemia (SRS) in Atlantic salmon (Salmo salar) remains largely unexplored. In our study, we evaluated the effect of P. salmonis LF-89-like and EM-90-like co-infection on post-smolt Atlantic salmon after an intraperitoneal challenge to compare changes in disease dynamics and host immune response. Co-infected fish had a significantly lower survival rate (24.1%) at 21 days post-challenge (dpc), compared with EM-90-like single-infected fish (40.3%). In contrast, all the LF-89-like single-infected fish survived. In addition, co-infected fish presented a higher presence of clinical lesions than any of the single-infected fish. The gene expression of salmon immune-related biomarkers evaluated in the head kidney, spleen, and liver showed that the EM-90-like isolate and the co-infection induced the up-regulation of cytokines (e.g., il-1β, ifnγ, il8, il10), antimicrobial peptides (hepdicin) and pattern recognition receptors (PRRs), such as TLR5s. Furthermore, in serum samples from EM-90-like and co-infected fish, an increase in the total IgM level was observed. Interestingly, specific IgM against P. salmonis showed greater detection of EM-90-like antigens in LF-89-like infected fish serum (cross-reaction). These data provide evidence that P. salmonis LF-89-like and EM-90-like interactions can modulate SRS disease dynamics in Atlantic salmon, causing a synergistic effect that increases the severity of the disease and the mortality rate of the fish. Overall, this study contributes to achieving a better understanding of P. salmonis population dynamics.

In Chile, Piscirickettsia salmonis contains two genetically isolated genogroups, LF-89 and EM-90. However, the impact of a potential co-infection with these two variants on Salmonid Rickettsial Septicemia (SRS) in Atlantic salmon (Salmo salar) remains largely unexplored. In our study, we evaluated the effect of P. salmonis LF-89-like and EM-90-like co-infection on post-smolt Atlantic salmon after an intraperitoneal challenge to compare changes in disease dynamics and host immune response. Co-infected fish had a significantly lower survival rate (24.1%) at 21 days post-challenge (dpc), compared with EM-90-like single-infected fish (40.3%). In contrast, all the LF-89-like single-infected fish survived. In addition, co-infected fish presented a higher presence of clinical lesions than any of the single-infected fish. The gene expression of salmon immune-related biomarkers evaluated in the head kidney, spleen, and liver showed that the EM-90-like isolate and the co-infection induced the up-regulation of cytokines (e.g., il-1β, ifnγ, il8, il10), antimicrobial peptides (hepdicin) and pattern recognition receptors (PRRs), such as TLR5s. Furthermore, in serum samples from EM-90-like and co-infected fish, an increase in the total IgM level was observed. Interestingly, specific IgM against P. salmonis showed greater detection of EM-90-like antigens in LF-89-like infected fish serum (cross-reaction). These data provide evidence that P. salmonis LF-89-like and EM-90-like interactions can modulate SRS disease dynamics in Atlantic salmon, causing a synergistic effect that increases the severity of the disease and the mortality rate of the fish. Overall, this study contributes to achieving a better understanding of P. salmonis population dynamics. [ABSTRACT FROM AUTHOR]

The major ingredient in ice-cream a popular children favourite snack, commonly sold to them at their school gate during the dry season is yoghurt. Therefore this paper investigates the bacteria load in these yoghurt ice-creams are important as they determine the health of the consumers. The bacteria load of four commercially sold yoghurt samples in Warri, Delta State, Nigeria using standard methods. Results reveal the presence of Streptococcus thermophilus, Streptococcus salivarius and Lactobacillus bulgaricus spp. The highest number of colonies were observed in CS1[NA, 232 and PC, 218] and CS2 [NA, 282 and PC, 91] while lower number of colonies were observed in HO [NA, 120 and PC, 90] and for NY [NA, 118 and PC, 112]. It was observed that Colony Forming Units for Nutrient Agar (NA) were consistently higher in all four brands of yoghurt than Colony Forming Units for Plate Count Agar. An average of 157 colonies were observed on both nutrient Agar and Plate count Agar. Colonies observed was similar in both Plate Count Agar and Nutrient Agar in the 4 brands of yoghurt. All the isolates were highly susceptible to Norfloxacin and resistant to Gentamicin, Drovid and Clindamycin. The results of the microbial quality indicate that the yoghurt are of acceptable food quality, with probiotic potential. [ABSTRACT FROM AUTHOR]

This study examined 75 samples of raw meat from cows and camels sold in local marketplaces in the governorate of Najaf/ Iraq, for bacterial load and heavy metal contamination. The culture results were classified into 10 types involving E. coli (36–90%) (31–88.5%), Enterobacter spp. (7–17.5%) (3–8.5%), Pseudomonas spp. (10–25%) (8–22.8%), Klebsiella spp. (3–7.5%) (4–11.4%), Staphylococcus aureus (4–10%) (5–14.2%), Staphylococcus epidermidis (5–12.5%) (5–14.2%), Proteus spp. (5–12.5%) (6–17.1%), E. coli O157 (6–15%) (2–5.7%), Yersinia enterocolitica (3–7.5%) (4–11.2%), and Salmonella spp. (3–7.5%) (4–11.2%), from cows and camels respectively. The averages of heavy metals concentrations in cow meat samples were 0.54±0.25, 0.50±0.18, 0.33±0.22, 0.22±2.5, 1.0±0.25 mg/kg; however, in camel meat samples were 0.27±0.20, 0.31±0.12, 0.26±0.11, 0.17±1.5 and 0.5±0.15 mg/kg for Lead (Pb), Cadmium (Cd), Copper (Cu), Nickel (Ni) and Zinc (Zn) respectively. The presence of significant levels of pathogenic microorganisms and metals in the meat samples indicates poor sanitation and hygiene practices during dealing with meat through steps of production, packaging, transportation, and storage, and the high amounts of heavy metal contamination in the environment, which will have an impact on the meat and milk animal products. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine the role of cerebrospinal fluid (CSF) bacterial load in adults with pneumococcal meningitis. We quantified bacterial load in CSF samples from the diagnostic lumbar puncture of adults with community-acquired pneumococcal meningitis. We also measured CSF concentrations of complement component 5a (C5a), and determined associations between bacterial load, clinical characteristics, C5a and unfavourable outcome (Glasgow Outcome Scale score <5). Bacterial load was quantified in 152 CSF samples. Median age of these patients was 61 years (interquartile range [IQR] 51–68), and 69 of 152 (45%) were female. Median CSF bacterial load was 1.6 × 104 DNA copies/mL (IQR 3.4 × 103–1.2 × 105), and did not correlate with CSF white cell count nor with CSF protein concentrations. Median CSF C5a concentration was 35.8 mg/L (IQR 15.9–105.6), and was moderately correlated with CSF bacterial loads (Spearman's rho = 0.42; p < 0001). High bacterial loads were associated with development of complications, such as circulatory shock (OR per logarithmic increase: 2.4, 95% CI: 2.0–2.9; p < 0.001) and cerebrovascular complications [OR: 1.9, 95% CI: 1.6–2.3; p < 0.001]). High bacterial loads were also associated with unfavourable outcome (OR: 2.8, 95% CI: 2.4–3.3; p < 0.001) and death (OR: 3.1, 95% CI: 2.6–3.8; p < 0.001). In a multivariable regression model including age, immunocompromised state, extrameningeal infection focus, admission Glasgow Coma Scale score and CSF C5a concentration, CSF bacterial load remained an independent predictor of unfavourable outcome (adjusted OR: 2.5, 95% CI: 1.6–3.9; p < 0.001). High CSF bacterial load predicts the development of complications and unfavourable outcome in adults with pneumococcal meningitis. [ABSTRACT FROM AUTHOR]

To the best of our knowledge, this paper presents the first report on the microbial status of wild bees (A. dorsata and A. florea) honey collected from different northern states of India. In total, 17 bacterial morphotypes (9 from A. dorsata and 8 from A. florea) were recovered. The bacterial load (log CFU/g) was observed to be maximum (4.01) in A. dorsata honey from Sirmour-Puruwala whereas, lowest load (3.49) was recorded in Punjab-Rupnagar honey. Likewise, A. florea honey from Sirmour-Kala Amb and Punjab-Doraha were recorded with maximum and minimum bacterial loads of 4.17 and 3.40, respectively. Observance of lower bacterial load than hazardous limit ensured its safety for human consumption. Three most dominant bacteria viz., AD1, HF7 and AF4 were identified as Micrococcus endophyticus (MT938911), Bacillus subtilis subsp. stercoris (MT764923) and Bacillus pumilus (MT764923), respectively through 16S rRNA ribotyping. Moreover, the inhibitory activity of honey was good to excellent against Salmonella typhi NCTC 786 and fair to good against Bacillus subtilis ATCC 6633, Pseudomonas aeruginosa ATCC 10662 and Klebsiella pneumoniae ATCC 13883. The Escherichia coli ATCC 1041 was the most sensitive bacterium among all. These results justify wild bees honey as a natural remedy for curing and preventing numerous human ailments. [ABSTRACT FROM AUTHOR]

Smartphones in medical settings pose infection risks due to harbouring pathogenic bacteria. This pilot study assessed the effectiveness duration of sanitization methods, focusing on 70% isopropyl alcohol wipes and ultraviolet-C (UVC) boxes, aiming to obtain preliminary data on the reduction in total bacterial load 3 h post-sanitization. A randomized monocentric trial with two intervention arms (wipes and UVC boxes) was designed. As participants, healthcare workers from three wards at Fondazione Policlinico Universitario 'A. Gemelli' IRCCS Hospital were recruited, stratified by ward, and block randomized within each ward to control confounders. Seventy-one healthcare workers, mostly nurses (62%) were included in the study. Initial bacterial load reduction was significant with both disinfection techniques, but after 3 h both methods showed increased bacterial levels, with wipes displaying potentially higher residual efficacy (P =0.056). To adequately size a trial (89% power, significance level 0.05) for assessing the residual efficacy of alcohol-impregnated wipes compared with UVC boxes at 3 h post-sanitization, 503 professionals per group were required. This study highlights the necessity for guidelines on hospital smartphone sanitization and educational initiatives for healthcare workers and patients. Further studies, adequately sized, are necessary to determine optimal sanitization intervals and assess pathogen transmission risks. [ABSTRACT FROM AUTHOR]

Background: Water quality and safety are fundamental to human development and well-being. Therefore, the purpose of this study was to determine the bacteriological and mineral content of water in Ho, the capital city of the Volta Region of Ghana. Methods: Sachet, bottled, and tap water were sampled from January to February in 2019 due to the high rate of consumption and their presumed quality which were taken at random from five different locations throughout the municipality. Water quality assessment protocols were utilized to ascertain the bacteriological as well as mineral contents of the samples, whilst ANOVA was used to determine statistical difference and significance at p

Bacterial killing in patients with tuberculosis (TB) relapse was compared to that in patients achieving cure, measured by TB molecular bacterial load assay (TB-MBLA) or mycobacteria growth indicator tube (MGIT) time to positivity (TTP). TB-MBLA in 4 relapsed patients was significantly different compared to 132 cured patients after 2 weeks of treatment; MGIT TTP showed a significant difference from week 8.

Background: The aim of this study was to evaluate the biogas production of chicken manure (CM) co‐digestion with different types of household waste (soft organic [SO] and food waste [FW]), as well as to evaluate the bacterial load of feeding stock and digested slurry samples before and after anaerobic digestion (AD). The experiment was carried out using lab‐based prototype digesters for co‐digestion of CM with different household wastes (5%). Three experimental groups (T1, T2, and T3) were designed using mixing ratios of SO:CM:H2O:inoculum (5:22.5:22.5:50), FW:CM:H2O:inoculum (5:22.5:22.5:50), and (SO + FW):CM:H2O:inoculum (2.5 + 2.5:22.5:22.5:50). The digesters were set at 28–34°C for 30 days for hydraulic retention time (HRT). Total viable count (TVC), Escherichia coli, and Salmonella spp. counts were determined using the spread plate technique. Results: The study revealed that the highest average cumulative biogas yield was achieved from T1 > T3 > T2, but the concentration of CH4 was found in T3 > T2 > T1. The biogas production between the three groups was statistically nonsignificant (p > 0.05) but the daily concentration of CH4 was found statistically significant (p < 0.05). The average concentration of CH4 and CO2 in biogas was found to be 30% and 68% for T1, 60% and 37% for T2, and 69% and 27% for T3. However, the H2S content was within the acceptable range. The bacterial load was decreased by 2–3 logs before and after AD, and this reduction was statistically significant (p < 0.05). Conclusion: The research found that the co‐digestion of CM with combined household wastes increased the methane concentration in biogas. [ABSTRACT FROM AUTHOR]

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Vibrio harveyi, a recently discovered pathogenic bacterium isolated from American eels (Anguilla rostrata), poses uncertainties regarding its pathogenesis in American eel and the molecular mechanisms underlying host defense against V. harveyi infection. This study aimed to determine the LD50 of V. harveyi in American eel and assess the bacterial load in the liver, spleen, and kidney post-infection with the LD50 dose. The results showed that the LD50 of V. harveyi via intraperitoneal injection in American eels over a 14d period was determined to be 1.24 × 103 cfu/g body weight (6.2 × 104 cfu/fish). The peak bacterial load occurred at 36 h post-infection (hpi) in all three organs examined. Histopathology analysis revealed hepatic vein congestion and thrombi, tubular vacuolar degeneration, and splenic bleeding. Moreover, quantitative reverse transcription polymerase chain reaction (qRT-PCR) results indicated significant up or downregulation of 18 host immune- or anti-infection–related genes post 12 to 60 hpi following the infection. Additionally, RNA sequencing (RNA-seq) unveiled 7 hub differentially expressed genes (DEGs) and 11 encoded proteins play crucial roles in the anti-V. harveyi response in American eels. This study firstly represents the comprehensive report on the pathogenicity of V. harveyi to American eels and RNA-seq of host's response to V. harveyi infection. These findings provide valuable insights into V. harveyi pathogenesis and the strategies employed by the host's immune system at the transcriptomic level to combat V. harveyi infection. [ABSTRACT FROM AUTHOR]

Aphids shelter several bacteria that benefit them in various ways. The associates having an obligatory relationship are non-culturable, while a few of facultative associates are culturable in insect cell lines, axenic media or standard microbiology media. In the present investigation, isolation, and characterization of the culturable bacterial associates of various aphid species, viz., Rhopalosiphum maidis, Rhopalosiphum padi, Sitobion avenae, Schizaphis graminum, and Lipaphis erysimi pseudobrassicae were carried out. A total of 42 isolates were isolated using different growth media, followed by their morphological, biochemical, and molecular characterization. The isolated culturable bacterial associates were found to belong to the genera Acinetobacter, Bacillus, Brevundimonas, Cytobacillus, Fictibacillus, Planococcus, Priestia, Pseudomonas, Staphylococcus, Sutcliffiella, and Tumebacillus which were grouped under seven families of four different orders of phyla Bacillota (Firmicutes) and Pseudomonata (Proteobacteria). Symbiont–entomopathogen interaction study was also conducted, in which the quantification of colony forming units of culturable bacterial associates of entomopathogenic fungal-treated aphids led us to the assumption that the bacterial load in aphid body can be altered by the application of entomopathogens. Whereas, the mycelial growth of entomopathogens Akanthomyces lecanii and Metarhizium anisopliae was found uninhibited by the bacterial associates obtained from Sitobion avenae and Rhopalosiphum padi. Analyzing persistent aphid microflora and their interactions with entomopathogens enhances our understanding of aphid resistance. It also fosters the development of innovative solutions for agricultural pest management, highlighting the intricate dynamics of symbiotic relationships in pest management strategies. [ABSTRACT FROM AUTHOR]

Objectives: Effective disinfection of the root canals is the cornerstone of successful endodontic treatment. Diminishing the microbial load within the root canal system is crucial for healing in endodontically treated teeth. The aim of this study was to evaluate the effect of 2780 nm Er,Cr:YSGG and 940 nm diode lasers on the eradication of microorganisms from single-rooted teeth with asymptomatic apical periodontitis. Materials and Methods: Thirty participants conforming to the inclusion criteria were randomly divided into 3 groups according to the disinfection protocol used; Conventional group: 2.5% Sodium Hypochlorite (NaOCl) and 17% EDTA solution NaOCl/EDTA, Dual laser group: 2780 nm Erbium, chromium: yttrium scandium-gallium-garnet (Er,Cr:YSGG) laser and 940 nm diode laser Er,CrYSGG/Diode, and Combined group: 17% EDTA and 940 nm diode laser EDTA/Diode. Bacterial samples were collected before and after intervention. The collected data were statistically analyzed using Friedman’s test and Kruskal–Wallis test (P ≤ 0.05). Results: The results of the study showed that both dual laser Er,CrYSGG/Diode and combined laser EDTA/Diode groups showed significantly less mean Log10 CFU/ml of aerobic and anaerobic bacterial counts than the conventional NaOCl/EDTA group. Conclusions: In this study we evaluated in vivo the bactericidal efficacy of three disinfection protocols for endodontic treatment of single-rooted teeth with apical periodontitis. The results indicated that both dual laser Er,CrYSGG/Diode and combined laser EDTA/Diode groups provide superior bactericidal effect compared to the conventional NaOCl/EDTA group. Clinical relevance: The integration of lasers into root canal disinfection protocols has demonstrated significant bacterial reduction which might promote healing and long-term success. [ABSTRACT FROM AUTHOR]

The present study evaluated the effect of two different antibiotic combinations SP (streptomycin, penicillin) and GTLS (gentamicin, tylosin, lincomycin and spectinomycin), as antibiotic regimens in TCFY (Tris-citric acid-fructose-yolk) semen extender on Surti buffalo bull semen. A total of 12 ejaculates from 6 bulls were collected. After evaluation of the dilution rate, the fresh semen was divided into three parts. Each part of the semen was extended upto 80 million spermatozoa/mL. One control group (part 1) was maintained with no antibiotics, while antibiotic combination SP and GTLS was added into part 2 and part 3 at the concentration of streptomycin 1000 µg/mL, penicillin 1000 IU/mL (Treatment-1), and gentamicin 500 µg/mL, tylosin 100 µg/mL, lincomycin 300 µg/mL and spectinomycin 600 µg/mL (Treatment-2). Pre-freeze and post-thaw microbial load (CFU/mL) and sperm abnormalities were found to be significantly (p<0.05) lower, whereas individual progressive sperm motility, live sperm percentage and HOS responsive spermatozoa were significantly (p<0.05) higher in semen samples treated with antibiotic combinations SP and GTLS in comparison to control. Further, the GTLS had a significantly (p<0.05) lower bacterial load at the pre-freeze and post-thaw stage as compared to SP. However, the observations on sperm parameters with SP and GTLS were statistically similar. It was concluded that SP and GTLS in semen extender show significant improvement in pre-freeze and post-thawed semen quality, statistically both at par as compared to control, and more efficiently reduced the bacterial load compared to SP and non-added control suggesting its preference for use in bovine frozen semen extender. [ABSTRACT FROM AUTHOR]

With the changing regulations in poultry processing, increased pressure is placed on integrators to reduce the number of human enteropathogenic bacteria on the final carcass and/or parts. Reducing the total number of bacteria on broiler carcasses before entering the evisceration side of the processing plant is projected to reduce the number of bacteria on the carcasses after chilling. This study was designed to evaluate the efficacy of a prototype wash cabinet using low volume, fluidic nozzles in combination with high pressure (450 psi) and hot water (60 °C) to remove bacteria from pre-scald, post-scald, or post picked carcasses. Carcasses (n = 5) from each location were obtained from a commercial processing plant, placed into individual sterile sample bags, placed into an insulated container, and transported to the U.S. National Poultry Research Center Pilot Plant within 30 min of collection. Carcasses were hung in standard shackles and sampled pre-wash with pre-moistened, cellulose swabs. All carcasses were washed in the prototype wash cabinet with 60 °C water at 450 psi at a line speed of 52 birds/minute on 15.24 cm centered shackles. Post-wash breast sponge samples were collected identical to pre-wash swabs. Buffered peptone water (BPW) was added, sponges stomached and serially diluted before plating onto total aerobic count (TAC), Enterobacteriaceae (ENT) and Escherichia. coli (EC) Petrifilm® cards. All PetriFilm® cards were incubated at 37 °C for 24 ± 2 h. After incubation, bacterial counts were recorded and converted to log10 CFU/swab. Samples were processed for Campylobacter species using the Tempo® CAM protocol. Four replications were conducted on separate dates. Paired t-tests were used to compare numbers recovered from breast swabs collected before and after the wash cabinet, significance reported at p < 0.05. Pre-scald samples had significant reductions of 2.50, 2.01, and 1.73 log10 colony-forming units/carcass (CFU/carcass) for TAC, Ent, and EC Petrifilm®, respectively, and a 2.21 CFU/mL reduction of Campylobacter species using Tempo® CAM. Post-scald, there were significant reductions of 2.09, 1.23, and 0.90 CFU/carcass for TA, Ent, and EC Petrifilm®, respectively, and a 1.14 CFU/mL reduction of Campylobacter species using Tempo® CAM. Post-pick, significant reductions of 0.73, 1.53, and 0.99 CFU/carcass for TA, Ent, and EC Petrifilm®, respectively, and a 0.86 CFU/carcass reduction of Campylobacter species using Tempo® CAM were reported. These data indicate that hot water at high pressure can reduce total bacterial load on carcasses and reduce pathogenic bacteria on carcasses prior to evisceration. [ABSTRACT FROM AUTHOR]

Background: Water quality and safety are fundamental to human development and wellbeing. Therefore, the purpose of this study was to determine the bacteriological and mineral content of water in Ho, the capital city of the Volta Region of Ghana. Methods: Sachet, bottled, and tap water were sampled from January to February in 2019 due to the high rate of consumption and their presumed quality which were taken at random from five different locations throughout the municipality. Water quality assessment protocols were utilized to ascertain the bacteriological as well as mineral contents of the samples, whilst ANOVA was used to determine statistical difference and significance at p<0.05. Results: The maximum Heterotrophic Plate Count for tap water was 9.95±0.64x105 Colony Forming Unit (CFU)/ml, for sachet water was 7.46±0.09x106 CFU/ml, and for bottled water was 1.10±0.56x105 CFU/ml, all obtained on nutrient agar. For MacConkey agar, maximum growth was 2.94±0.03x106, 9.42±1.67x106, and 2.31±0.77x105 CFU/ml for tap, sachet, and bottled water, respectively. The Xylose Lysine Deoxycholate Agar indicated maximum growth of 1.84±0.34x10³, 5.72±0.06x106, and 5.50±2.12x104 CFU/ml for tap, sachet, and bottled water, respectively. The physical parameters such as pH, turbidity, color, and conductivity were within the recommended limits set by the Ghana Standards Authority. However, tap water recorded the highest turbidity, bottled water recorded the highest and least pH and turbidity, respectively. Moreover, the mineral analysis revealed high levels of phosphate (PO43-), chloride (C-), and sodium (Na) in bottled water, and total iron (Fe) was relatively high in several tap and sachet water samples, the latter item also recorded the highest for ammonia (NH3). Conclusions: Overall, the tap, sachet, and bottled water samples exhibited varied levels of microbial, and mineral contents whilst the physical parameters were relatively within the recommended levels. The sachet and tap water were the least wholesome in comparison with the bottled water samples. [ABSTRACT FROM AUTHOR]

ABSTRACT: The incidence of chronic respiratory disease (CRD) due to Mycoplasma gallisepticum (MG) contamination in hatching eggs poses a serious threat to poultry health and hatchability. Implementing effective sanitization methods while safeguarding the hatching potential of embryos is crucial. This study aimed to explore novel techniques for sanitizing hatching-fertile eggs to prevent and manage MG-associated CRD. The primary objective was to assess the efficacy of acidic electrochemically stimulated water (ECS), focusing on MG disinfection. Additionally, the study investigated 2 application methods, 1) electrostatic disinfection (ED) and 2) cold fog (CF) disinfection, to evaluate their bactericidal effects against MG-contaminated eggs. Deliberately infected MG strains were used for the experimental design, which compared the disinfection efficacy of ECS with its acidic properties. The comparison involved ED, which applies an electrostatic charge to water particles, and CF disinfection, a cold mist technique. Both methods aimed to target MG without compromising egg-hatching potential. The results indicated a significant (p < 0.05) reduction in colony-forming units per milliliter (CFU/mL). However, both application methods demonstrated distinct bactericidal effects. Eggs treated with electrostatic disinfection showed a significant (p < 0.001) reduction in embryonic mortality during incubation (10%) compared to control untreated eggs (18%). Similarly, the CF method exhibited a significant (p < 0.001) decrease in embryonic mortality (13%). The ECS potential in reducing embryonic mortality within the pH range of 2.5 to 6.5 was noted. Both the ED and CF methods show promise for preventing MG-induced hatchery infection while maintaining egg-hatching potential. This study presents innovative techniques to control MG in hatching eggs, contributing to improved poultry health and reduced CRD incidence.

Fitness centers offer an opportunity for investigating the indirect transmission of pathogens. Many people with varying levels of personal hygiene share sports equipment where direct surface-to-skin contact occurs. This study aimed to investigate the bacterial load and fungal and methicillin-resistant Staphylococcus aureus (MRSA) contamination on predetermined sports equipment in fitness centers in Northern Cyprus. Additionally, volunteer personal trainers and gym members were screened to detect whether they were carriers of MRSA. Samples were collected from six fitness centers on sports equipment. MRSA carrier status was investigated for personal trainers (n=10) and gym members (n=100). The study used culture-dependent techniques and used SPSS 20 software for statistical analysis. There was no statistically significant difference between fungal growth on the sports equipment, and Aspergillus spp. were predominant. However, one of the fitness centers had a statistically significant difference in fungal growth compared to the others (p

The major ingredient in ice-cream a popular children favourite snack, commonly sold to them at their school gate during the dry season is yoghurt. Therefore this paper investigates the bacteria load in these yoghurt ice-creams are important as they determine the health of the consumers. The bacteria load of four commercially sold yoghurt samples in Warri, Delta State, Nigeria using standard methods. Results reveal the presence of Streptococcus thermophilus, Streptococcus salivarius and Lactobacillus bulgaricus spp. The highest number of colonies were observed in CS1[NA, 232 and PC, 218] and CS2 [NA, 282 and PC, 91] while lower number of colonies were observed in HO [NA, 120 and PC, 90] and for NY [NA, 118 and PC, 112]. It was observed that Colony Forming Units for Nutrient Agar (NA) were consistently higher in all four brands of yoghurt than Colony Forming Units for Plate Count Agar. An average of 157 colonies were observed on both nutrient Agar and Plate count Agar. Colonies observed was similar in both Plate Count Agar and Nutrient Agar in the 4 brands of yoghurt. All the isolates were highly susceptible to Norfloxacin and resistant to Gentamicin, Drovid and Clindamycin. The results of the microbial quality indicate that the yoghurt are of acceptable food quality, with probiotic potential.

Objective: To evaluate the effectiveness of the Modified Kenneth Jones Scoring System as a screening tool for diagnosing pulmonary tuberculosis in children. Methodology: A cross sectional study was conductedto assess the symptoms of tuberculosis among 100 pediatric patients with male to female ratio was 67:33. through Modified Kenneth Jones Scoring System (MKJSC) at Gulab Devi Tertiary Care Hospital, Lahore from June-December, 2022. The study included symptoms based on gender, drug usage and microbial load. Patients diagnosed with TB were included in this study to assess the system's effectiveness in identifying specific symptoms and clinical manifestations of TB. This inclusion allowed for a comprehensive evaluation of the MKJSC's diagnostic accuracy and its potential utility in early detection and intervention in pediatric TB cases. The Data was analyzed using SPSS to identify specific symptoms. Results: The Modified Kenneth Jones Criteria diagnosed 65 patients out of 100 with one false positive. The sensitivity for TB detection was 84.2% (95% CI: 73.6% - 91.2%), specificity was 95.8% (95% CI: 76.8% - 99.7%), positive predictive value was 98.4% (95% CI: 90.5% - 99.9%), and negative predictive value was 65.7% (95% CI: 47.7% - 80.3%). Statistical analysis with 5% confidence interval revealed a medium of age of 73 months and a mode of 120 months among patients. While cough prevalence varied, all patients had a history of prolonged fever. Meningeal irritation was observed in 52% of participants and 77% had contact with TB patients. Other findings included malnutrition 50%, pneumonia 48% and BCG screening 24%. Conclusion: The Modified Kenneth Jones Scoring System demonstrated high sensitivity and specificity in detecting tuberculosis, outperforming previous methods. It proves to be an effective tool in resource-limited healthcare settings for diagnosing TB in children.

With the changing regulations in poultry processing, increased pressure is placed on integrators to reduce the number of human enteropathogenic bacteria on the final carcass and/or parts. Reducing the total number of bacteria on broiler carcasses before entering the evisceration side of the processing plant is projected to reduce the number of bacteria on the carcasses after chilling. This study was designed to evaluate the efficacy of a prototype wash cabinet using low volume, fluidic nozzles in combination with high pressure (450 psi) and hot water (60 °C) to remove bacteria from pre-scald, post-scald, or post picked carcasses. Carcasses (n = 5) from each location were obtained from a commercial processing plant, placed into individual sterile sample bags, placed into an insulated container, and transported to the U.S. National Poultry Research Center Pilot Plant within 30 min of collection. Carcasses were hung in standard shackles and sampled pre-wash with pre-moistened, cellulose swabs. All carcasses were washed in the prototype wash cabinet with 60 °C water at 450 psi at a line speed of 52 birds/minute on 15.24 cm centered shackles. Post-wash breast sponge samples were collected identical to pre-wash swabs. Buffered peptone water (BPW) was added, sponges stomached and serially diluted before plating onto total aerobic count (TAC), Enterobacteriaceae (ENT) and Escherichia. coli (EC) Petrifilm® cards. All PetriFilm® cards were incubated at 37 °C for 24 ± 2 h. After incubation, bacterial counts were recorded and converted to log10 CFU/swab. Samples were processed for Campylobacter species using the Tempo® CAM protocol. Four replications were conducted on separate dates. Paired t-tests were used to compare numbers recovered from breast swabs collected before and after the wash cabinet, significance reported at p < 0.05. Pre-scald samples had significant reductions of 2.50, 2.01, and 1.73 log10 colony-forming units/carcass (CFU/carcass) for TAC, Ent, and EC Petrifilm®, respectively, and a 2.21 CFU/mL reduction of Campylobacter species using Tempo® CAM. Post-scald, there were significant reductions of 2.09, 1.23, and 0.90 CFU/carcass for TA, Ent, and EC Petrifilm®, respectively, and a 1.14 CFU/mL reduction of Campylobacter species using Tempo® CAM. Post-pick, significant reductions of 0.73, 1.53, and 0.99 CFU/carcass for TA, Ent, and EC Petrifilm®, respectively, and a 0.86 CFU/carcass reduction of Campylobacter species using Tempo® CAM were reported. These data indicate that hot water at high pressure can reduce total bacterial load on carcasses and reduce pathogenic bacteria on carcasses prior to evisceration.

AbstractAn outbreak of a disease with a high mortality rate occurred in a Chinese Softshell Turtle (Pelodiscus sinensis) farm in Hubei Province. This study isolated a highly pathogenic Bacillus cereus strain (Y271) from diseased P. sinensis. Y271 has β hemolysis, containing both Hemolysin BL (hblA, hblC, and hblD), Non-hemolytic enterotoxin, NHE (nheA, nheB, and nheC), and Enterotoxin FM (entFM) genes. Y271 is highly pathogenic against P. sinensis with an LD50 = 6.80 × 103 CFU/g weight. B. cereus was detected in multiple tissues of the infected P. sinensis. Among them, spleen tissue showed the highest copy number density (1.54 ± 0.12 × 104 copies/mg). Multiple tissues and organs of diseased P. sinensis exhibited significant pathological damage, especially the spleen, liver, kidney, and intestine. It showed obvious tissue structure destruction, lesions, necrosis, red blood cells, and inflammatory cell infiltration. B. cereus proliferating in the spleen, liver, and other tissues was observed. The intestinal microbiota of the diseased P. sinensis was altered, with a greater abundance of Firmicutes, Fusobacterium, and Actinomyces than in the healthy group. Allobaculum, Rothia, Aeromonas, and Clostridium abundance were higher in the diseased group than in the healthy group. The number of unique microbial taxa (472) in the disease group was lower than that of the healthy group (705). Y271 was sensitive to multiple drugs, including florfenicol, enrofloxacin, neomycin, and doxycycline. B. cereus is the etiological agent responsible for the massive death of P. sinensis and reveals its potential risks during P. sinensis cultivation.

The treatment and utilization of cheese whey (W) represents one of the major challenges facing the dairy industry. In this work the production of Chlorella vulgaris and its potential use in recovering the main nutrients (N, P and C) from cheese whey was evaluated in batch and continuous mode. Four different treatments were evaluated: Fertilizers-control (100% freshwater plus chemical fertilizers); Fertilizers-2.5%W (v/v), Fertilizers-5%W (v/v) and Fertilizers-10%W (v/v). The biomass productivity was affected by the percentage of cheese whey added, resulting in a 2.8-fold increase when adding 10% cheese whey to the culture medium. In addition, the cheese whey concentration in the culture medium also affected the overall macromolecular composition of the biomass along with the appearance and growth of aerobic mesophilic bacteria. Despite the high concentration of organic matter in the cheese whey (COD, 60.000 mg L-1), C.vulgaris was able to recover more than 80% of COD in continuous mode, along with 94 % and 60% of TN and TP, respectively. These promising results can be explained by the mixotrophic activity of C.vulgaris, which was demonstrated by the decrease in the chlorophyll content when cheese whey was added to the culture medium and by photo-respirometric assays. The use of cheese whey for microalgal biomass production represents a sustainable alternative to revaluate this by-product stream and contribute to the circular economy. [ABSTRACT FROM AUTHOR]

In poultry slaughtering, cross-contamination with Salmonella Enteritidis is a constant ongoing challenge. Interaction between food contact surfaces can potentially transfer pathogenic material like feces from carcasses to another one. One approach to break this chain is to modify surfaces that frequently come into contact with the animal during the slaughtering process. Surface alterations like nanoscale coatings have already been successfully applied in various fields to lower the bacterial load. The aim of the study was to compare bacterial attachment, proliferation and detachment of Salmonella Enteritidis and Escherichia coli on uncoated and on nanoscale silica coated rubber picker fingers at laboratory scale. It was shown that both target organisms did not adhere less to coated surface than to uncoated picker fingers, whereas no difference in bacterial growth or detachment was detected. It can be concluded that the coating used in this study did not contribute to a reduction of the bacterial load on this surface in the specific experimental setups employed. Further studies should focus on whether nanoscale surface modifications achieve improved results under more practical conditions and whether other factors such as surface durability can be influenced by a coating. [ABSTRACT FROM AUTHOR]

Summary: Aim: This study aimed to verify the efficacy of disinfection procedures to reduce Acinetobacter baumannii blaOXA-23 bacterial load in needleless connectors that had been experimentally contaminated. Methods: Two-way intermediate extender's hub and needle-free valve were contaminated with Acinetobacter baumannii blaOXA-23. To disinfect them, the following procedures were carried out: sterile gauze with 70% ethanol, sterile gauze with Incidin®, and 70% isopropyl alcohol single-use cap, with eight times friction for 10 s, followed by 5 s drying time. The statistical tests Kruskal–Wallis and post-hoc Conover were performed using MedCalc®. Results: A total of 82 experiments were conducted. All tested disinfection procedures were efficacious in reducing the A. baumannii blaOXA-23 load. The 70% IPA single-use cap was found to be the best method for disinfecting the two-way intermediate extender's hub (87.28%), while all the methods were efficacious for the disinfection of the needle-free valve (more than 90%). During the inoculation period, A. baumannii blaOXA-23 showed less adherence to the needle-free valve during the inoculation period, probably due to the device's design. Conclusion: The three tested disinfection procedures using sterile gauze with 70% ethanol, sterile gauze with Incidin®, and 70% IPA single-use cap were found to be efficacious in reducing the bacterial load of A. baumanni blaOXA-23 in needleless connectors. Proper disinfection of needleless connectors is a crucial nursing practice to prevent bloodstream infections, as it significantly reduces the bacterial load present in the device.

Not all patients produce sputum, yet most available TB tests use sputum. We investigated the utility of a novel RNA-based quantitative test, the tuberculosis molecular bacterial load assay (TB-MBLA), for the detection and quantification of Mycobacterium tuberculosis in stool. Stools from 100 adult individuals were treated with OMNIgene-sputum reagent and tested using Xpert MTB/RIF ultra (Xpert ultra), auramine O smear microscopy (smear), mycobacterial growth indicator tube (MGIT), and Lowenstein-Jensen (LJ) cultures. The remaining portions were frozen at -20°C and later tested by TB-MBLA. MGIT sputum culture was used as a TB confirmatory test and reference for stool tests. Sixty-one of 100 participants were already confirmed TB positive by MGIT sputum culture, 20 (33%) of whom were HIV coinfected. TB-MBLA detected M. tuberculosis in 57/100 stool samples, including 49 already confirmed for TB. The mean bacterial load measured by stool TB-MBLA was 5.67 ± 1.7 log10 estimated CFU (eCFU) per mL in HIV-coinfected participants, which was higher than the 4.83 ± 1.59 log10 eCFU per mL among the HIV-negative participants (P = 0.04). The sensitivities (95% confidence intervals [CI]) of stool assays were 80% (68 to 89) and 90% (79 to 98) for TB-MBLA and Xpert ultra, which were both higher than the 44% (32 to 58), 64% (51 to 76), and 62% (45 to 77) for smear, MGIT, and Lowenstein-Jensen (LJ) stool cultures, respectively. The specificity (95% CI) of stool assays was highest for smear, at 97% (87 to 100), followed by Xpert ultra at 91% (76 to 98), TB-MBLA at 79% (63 to 90), LJ at 80% (64 to 91), and MGIT at 62% (45 to 77). Twenty-six percent of MGIT and 21% of LJ stool cultures were indeterminate due to contamination. Detection and quantification of viable M. tuberculosis bacilli in stool raises its utility as an alternative to sputum as a sample type for TB diagnosis. IMPORTANCE This paper highlights the value of stool as a sample type for diagnosis of tuberculosis. While other studies have used DNA-based assays like the Xpert MTB/RIF and culture to detect Mycobacterium tuberculosis in stool, this is the first study that has applied TB-MBLA, an RNA-based assay, to quantify TB bacteria in stool. The high microbial density and diversity in stool compromises the specificity and sensitivity of culture-based tests due to overgrowth of non-M. tuberculosis flora. Consequently, TB-MBLA becomes the most sensitive and specific test for the detection and quantification of viable TB bacteria in stool. Most crucially, this study raises the possibility of a nonsputum alternative sample type for diagnosis of TB among people who have difficulty in producing sputum.

Background: The Xpert MTB/RIF (Xpert) assay has been widely used to diagnose suspected active tuberculosis (TB) and rifampicin-resistant TB cases. Despite its excellent performance record, false-positive Xpert rifampicin (RIF) resistance results are obtained for specimens with extremely low bacterial loads. Objective: We aimed to study the feasibility of repeat Xpert testing as a strategy for reducing the odds of obtaining false-positive results when testing paucibacillary TB patients. Methods: We enrolled previously tested TB patients with very low initial bacterial loads from May 2016 to February 2022 for Xpert retesting. A total of 251 TB patients were retested using the Xpert assay. Results: RIF resistance was noted in 65 (25.9 %) patients when tested by Xpert at initial diagnosis. Only 107 (42.6 %) of 251 patients tested positive for MTB when retested via Xpert. The majority (98.6 %) of RIF-susceptible cases were still susceptible to RIF when retested. Initial Xpert testing yielded 35 positive results for MTB in the RIF-resistant group, of whom 25 (71.4 %) still exhibited RIF resistance when retested. All culture-positive MTB isolates in the RIF-susceptible group were also RIF-susceptible by phenotypic DST. In the RIF-resistant group, 10 of 14 culture-positive MTB isolates exhibited RIF resistance, of which 4 isolates were deemed RIF-susceptible by phenotypic DST. The proportion of double mutations within the MTB rpoB RRDR sequence, as detected by hybridization of Xpert D and E probes, was significantly higher in the RIF-susceptible group than in the RIF-susceptible group. Conclusions: Our results demonstrated that initial RIF-susceptible results were more accurate than RIF-resistant results. Additionally, patients with double mutations that delayed probe D/E hybridization were more likely to have false-positive Xpert results. Our findings emphasize that repeat Xpert MTB/RIF testing is necessary for TB patients with extremely low bacterial loads who are at high risk for RIF-resistant TB.

ABSTRACT: In this study, 2 types of drinking water were provided to broiler chicks to evaluate the relationship between the bacterial load of drinking water and cecal microbiota. One type of drinking water was untreated, while the other type was daily treated with sodium dichlorocyanurate (50 mg/L). A total of 240 broiler chicks were divided into 2 groups based on their initial body weight. There were 6 replicates in each group, and each replicate cage contained 20 birds. Each cage was assigned to a different floor of the battery cage. On the final day, water samples were collected from each replicate cage at the opening of the drinking cup height, and one bird was selected from each replicate cage to obtain cecal content samples for measuring microbiota composition using the 16S rRNA technique. We found that drinking water treated with sodium dichlorocyanurate significantly reduced the richness and diversity of microbiota and diminished/disappeared most gram-negative bacteria. Broiler chicks that consumed chlorinated drinking water exhibited changes in the composition of cecal microbiota, with Alistipes serving as the marker species in the cecal content of broiler chicks that consumed untreated water, whereas AF12 served as the marker species in the cecal content of broiler chicks that consumed chlorinated drinking water. Functional prediction using the MetaCyc database and species composition analysis of metabolic pathways showed that changes in 7 metabolic pathways were related to the abundance of Providencia. Therefore, we concluded that chlorinated drinking water reduced the bacterial load in drinking water, thereby altering the cecal microbiota composition and regulating the metabolic activity of broiler chicks.

ABSTRACTAim Our aim was to compare the prevalence and load of nine pathobionts in subgingival samples of healthy individuals and periodontitis patients from four different countries.Methods Five hundred and seven subgingival biofilm samples were collected from healthy subjects and periodontitis patients in Belgium, Chile, Peru and Spain. The prevalence and load of Eubacterium brachy, Filifactor alocis, Fretibacterium fastidiosum, Porphyromonas endodontalis, Porphyromonas gingivalis, Selenomonas sputigena, Treponema denticola, Tannerella forsythia and Treponema socranskii were measured by quantitative PCR.Results The association with periodontitis of all species, except for T. socranskii, was confirmed in all countries but Peru, where only P. endodontalis, P. gingivalis and T. denticola were found to be significantly associated. Moreover, most species showed higher loads at greater CAL and PPD, but not where there was BOP. Through Principal Component Analysis, samples showed clearly different distributions by diagnosis, despite observing a smaller separation in Peruvian samples.Conclusions Unlike prevalence, relative load was found to be a reliable variable to discriminate the association of the species with periodontitis. Based on this, F. alocis, P. endodontalis, P. gingivalis, T. denticola and T. forsythia may be biomarkers of disease in Belgium, Chile and Spain, due to their significantly higher abundance in periodontitis patients.

Simple Summary: Nest box bacterial loads were studied during the prebreeding period in relation to nest box occupancy by Great Tits and Blue Tits in the previous season at two different study sites: an urban park site and a deciduous forest site. This analysis revealed that the interior bacterial load was higher in the nest boxes used in the previous season for breeding; however, the results were significant only in the forest area. In general, the bacterial load was significantly higher in the nest boxes placed in the forest study area than at the urban park site. Among the environmental factors that affect bird nesting in nest boxes, the influence of microbial communities is relatively poorly understood. In this study, nest boxes used for breeding by secondary cavity nesters were sampled before the start of the breeding season to assess the bacterial loads of the nest box in relation to their previous year status. Different parts of the wooden nest box offer variable conditions for the development of bacteria. During the breeding season, the nest box entrance hole is wiped out by birds, delivering bacteria to their bodies, but during winter, it is exposed to unfavourable external conditions. The interior of the nest box, in turn, is also wiped by birds, but the conditions during winter are more stable there. Therefore, samples from the entrance hole and the interior of the nest box were taken at two different study sites: an urban parkland and a natural forest. We predicted that both the occupancy of the nest boxes during the previous breeding season by birds and the nesting sites would influence the bacterial load of the nest box. To verify this prediction, two categories of nest boxes were sampled at both study sites: nest boxes occupied by any of the two tit species (Great Tit or Blue Tit) in the previous season for breeding and nest boxes that had remained empty that year. The interior bacterial load of the nest box was higher in the nest boxes occupied in the previous breeding season, but only in the forest area. Furthermore, the bacterial load of both the entrance hole of the nest box and the interior was significantly higher in the forest study area in both occupied and unoccupied nest boxes. Our results show that the bacterial load of the nest box is positively related to the presence of nests in the previous breeding season and can vary between different sites. [ABSTRACT FROM AUTHOR]

To investigate the efficacy of the supplementary use of a rotary agitation method [XP‐endo Finisher (XPF)] and sonically‐activated irrigation [EndoActivator (EA)], using droplet digital PCR (ddPCR) on reducing the bacterial load in previously root canal treated teeth with apical periodontitis. Twenty patients with post‐treatment apical periodontitis were allocated into two groups according to the irrigation activation method used: XPF and EA group. Total bacterial loads, as well as the amount of Enterococcus faecalis (E. faecalis) were determined before (S1) and after (S2) chemomechanical preparation, and after final irrigation activation (S3) by means of ddPCR. The bacterial copy numbers were compared between groups using the Friedman test (Nonparametric Repeated Measures ANOVA). When the groups were examined in terms of gender, age, number of root canals, periapical index score, sterility control total bacteria (SCTB), S1‐ and S2‐total bacteria copy number, it was found that there was no statistical difference between the XPF group and the EA group (p > 0.05). Subsequent activation (S3) resulted in a significant microbial reduction in both XPF and EA groups, both of which reduced significantly more bacteria than chemomechanical instrumentation (S2) (p < 0.0001). On the contrary, S3‐total bacteria copy number of the EA group was lower than the XPF group (p < 0.0147). There was no statistical difference between the XPF group and the EA group in terms of E. faecalis copy number (p > 0.05). Although both the XPF and the EA optimised the antibacterial efficiency of chemomechanical preparation in previously root canal‐treated teeth with apical periodontitis, a lower total bacterial copy number was achieved with the EA application than the XPF application. [ABSTRACT FROM AUTHOR]

Cities in Bangladesh produce large amounts of solid waste (SW) through various human activities which severely pollutes our native environment. As a result, SW pollutes the three basic environmental elements (air, water, and soil) by increasing pathogenic microbial load, which might be hazardous to public health directly or indirectly. In this study, we conducted 30 samples (i.e., soil, water, and air) collected from areas where municipal solid wastes are dumped (Tangail Sadar Upazila, Bangladesh). All the samples were analyzed to assess bacteriological quality for presumptive viable and coliform count using different agar media. We performed serial dilution 10−3–10−10 times for soil and water samples, and the diluted samples were spread on Mac‐Conkey agar and nutrient agar plates. For the air sample, the sterile media containing petri‐dish was placed adjacent to the dumpsite of the municipal waste and kept for an hour. Then all the samples were incubated at 37°C overnight for total viable count (TVC) and total coliform count (TCC). Biochemical tests and PCR were performed for the identification of these microorganisms. The antibiogram study was performed to reveal their (identified bacteria) susceptibility against clinically used antibiotics according to the standard disk diffusion technique. The highest bacterial loads were found in the air: TVC 3.273 × 103 and TCC 1.059 × 103 CFU/plate; tube‐well water: TVC 8.609 × 103, and TCC 8.317 × 103 CFU/mL; in surface water: TVC 6.24 × 1013 CFU/mL and TCC 2.2 × 1012 CFU/mL; in soil: TVC 2.88 × 1011 and TCC 1.02 × 1011 CFU/g, respectively. Microbes from SW can be transmitted through air, dust particles, or flies, and here we found an average of 1120 microbes spread over 63.61 cm2 area per hour. Eight bacterial isolates (Pseudomonas spp., Klebsiella spp., E. coli, Proteus spp., V. cholera, Salmonella spp., Shigella spp., and Vibrio spp.) were identified by the biochemical test. Among them, E. coli and Shigella spp. were further ensured by PCR targeting bfpA and ipaH genes. Antibiotic susceptibility test results showed that E. coli isolates were highly resistant to erythromycin (80%); Shigella spp. were resistant to nalidixic acid (90%), whereas Salmonella spp. was found resistant to kanamycin (90%). Vibrio spp. were also resistant to azithromycin (80%) and erythromycin (80%), which should be a great concern for us. A semi‐structured survey revealed that 63% of respondents suffered from different clinical conditions (intestinal diseases) due to SW pollution. So, steps should be taken to improve the proper management and disposal of solid waste and liquid effluent to save our environment and public health. [ABSTRACT FROM AUTHOR]

The antitumor efficacy of cancer immunotherapy can correlate with the presence of certain bacterial species within the gut microbiome. However, many of the molecular mechanisms that influence host response to immunotherapy remain elusive. In this study, we show that members of the bacterial genus Enterococcus improve checkpoint inhibitor immunotherapy in mouse tumor models. Active enterococci express and secrete orthologs of the NlpC/p60 peptidoglycan hydrolase SagA that generate immune-active muropeptides. Expression of SagA in nonprotective E. faecalis was sufficient to promote immunotherapy response, and its activity required the peptidoglycan sensor NOD2. Notably, SagA-engineered probiotics or synthetic muropeptides also augmented anti-PD-L1 antitumor efficacy. Taken together, our data suggest that microbiota species with specialized peptidoglycan remodeling activity and muropeptide-based therapeutics may enhance cancer immunotherapy and could be leveraged as next-generation adjuvants.

Rifampin or multidrug-resistant tuberculosis (RR/MDR-TB) treatment has largely transitioned to regimens free of the injectable aminoglycoside component, despite the drug class' purported bactericidal activity early in treatment. We tested whether Mycobacterium tuberculosis killing rates measured by tuberculosis molecular bacterial load assay (TB-MBLA) in sputa correlate with composition of the RR/MDR-TB regimen. Serial sputa were collected from patients with RR/MDR- and drug-sensitive TB at days 0, 3, 7, and 14, and then monthly for 4 months of anti-TB treatment. TB-MBLA was used to quantify viable M. tuberculosis 16S rRNA in sputum for estimation of colony forming units per ml (eCFU/ml). M. tuberculosis killing rates were compared among regimens using nonlinear-mixed-effects modeling of repeated measures. Thirty-seven patients produced 296 serial sputa and received treatment as follows: 13 patients received an injectable bedaquiline-free reference regimen, 9 received an injectable bedaquiline-containing regimen, 8 received an all-oral bedaquiline-based regimen, and 7 patients were treated for drug-sensitive TB with conventional rifampin/isoniazid/pyrazinamide/ethambutol (RHZE). Compared to the adjusted M. tuberculosis killing of -0.17 (95% confidence interval [CI] -0.23 to -0.12) for the injectable bedaquiline-free reference regimen, the killing rates were -0.62 (95% CI -1.05 to -0.20) log10 eCFU/ml for the injectable bedaquiline-containing regimen (P = 0.019), -0.35 (95% CI -0.65 to -0.13) log10 eCFU/ml for the all-oral bedaquiline-based regimen (P = 0.054), and -0.29 (95% CI -0.78 to +0.22) log10 eCFU/ml for the RHZE regimen (P = 0.332). Thus, M. tuberculosis killing rates from sputa were higher among patients who received bedaquiline but were further improved with the addition of an injectable aminoglycoside.

Abstract Enteric bacteria such as Escherichia coli and Salmonella spp. are significant fish pathogens and related to thousands of cases of food-borne diseases every year in human. Since aquatic environments are reservoirs of these pathogens, they may contaminate the food fish and result in outbreaks. Therefore, it is crucial to reduce or eliminate these pathogens from aquaculture facilities. We tested effectiveness of three commonly used aquaculture chemicals, viz., lime, hydrogen peroxide and zeolite on bacterial load, Escherichia coli and Salmonella spp. under laboratory and earthen pond conditions where they were applied at a dose recommended for freshwater aquaculture. Results of the bacteriological study showed that lime had a significant role in reducing bacterial abundance from an initial value of 1.5 × 103 to 1.9 × 103 cfu/ml and 3.9 × 103 to 6.3 × 103 to a final value of 1.2 × 103 to 1.5 × 103 cfu/ml and 1.9 × 103 to 6.3 × 103 cfu/ml within 24 h under aquaria and pond condition, respectively. A complete inactivation of E. coli was observed in lime treated aquaria and ponds 24 h post-treatment, whereas Salmonella spp. remained unaffected in pond water but inactivated under aquarium condition after same period. However, neither hydrogen peroxide nor zeolite treatment reduced total bacterial count as well as E. coli and Salmonella even after 1-week post-treatment. It is, therefore, recommended that the water treatment chemicals should be applied in aquaculture ponds at appropriate dose, and farmers need to adopt biosecurity measures to ensure food safety.