High Bacterial Load Research Articles

IL-17 mediates protective immunity against nasal infection with Bordetella pertussis by mobilizing neutrophils, especially Siglec-F+ neutrophils

Understanding the mechanism of protective immunity in the nasal mucosae is central to the design of more effective vaccines that prevent nasal infection and transmission of Bordetella pertussis. We found significant infiltration of IL-17-secreting CD4+ tissue-resident memory T (TRM) cells and Siglec-F+ neutrophils into the nasal tissue during primary infection with B. pertussis. Il17A−/− mice had significantly higher bacterial load in the nasal mucosae, associated with significantly reduced infiltration of Siglec-F+ neutrophils. Re-infected convalescent mice rapidly cleared B. pertussis from the nasal cavity and this was associated with local expansion of IL-17-producing CD4+ TRM cells. Depletion of CD4 T cells from the nasal tissue during primary infection or after re-challenge of convalescent mice significantly delayed clearance of bacteria from the nasal mucosae. Protection was lost in Il17A−/− mice and this was associated with significantly less infiltration of Siglec-F+ neutrophils and antimicrobial peptide (AMP) production. Finally, depletion of neutrophils reduced the clearance of B. pertussis following re-challenge of convalescent mice. Our findings demonstrate that IL-17 plays a critical role in natural and acquired immunity to B. pertussis in the nasal mucosae and this effect is mediated by mobilizing neutrophils, especially Siglec-F+ neutrophils, which have high neutrophil extracellular trap (NET) activity.

Two atypical gram-negative bacteria-binding proteins are involved in the antibacterial response in the pea aphid (Acyrthosiphon pisum).

The activation of immune pathways is triggered by the recognition of pathogens by pattern recognition receptors (PRRs). Gram-negative bacteria-binding proteins (GNBPs)/β-1,3-glucan recognition proteins (βGRPs) are a conserved family of PRRs in insects. Two GNBPs are predicted in the genome database of pea aphids; however, little is known about their functions in the aphid immune system. Here, we show that pea aphid GNBPs possess domain architectures and sequence features distinct from those of typical GNBPs/βGRPs and that their expression is induced by bacterial infection. Knockdown of their expression by dsRNA resulted in lower phenoloxidase activity, higher bacterial loads and higher mortality in aphids after infection. Our data suggest that these two atypical GNBPs are involved in the antibacterial response in the pea aphid, likely acting as PRRs in the prophenoloxidase pathway.

Bacteria of eleven different species isolated from biofilms in a meat processing environment have diverse biofilm forming abilities

Biofilms are formed by microorganisms protected by a self-produced matrix, most often attached to a surface. In the food processing environments biofilms endanger the product safety by the transmission of spoilage and pathogenic bacteria.In this study, we characterised the biofilm formation of the following eleven strains isolated from biofilms in a meat-processing environment: Acinetobacter harbinensis BF1, Arthrobacter sp. BF1, Brochothrix thermosphacta BF1, Carnobacterium maltaromaticum BF1, Kocuria salsicia BF1, Lactococcus piscium BF1, Microbacterium sp. BF1, Pseudomonas fragi BF1, Psychrobacter sp. BF1, Rhodococcus erythropolis BF1, Stenotrophomonas sp. BF1. We applied whole- genome sequencing and subsequent genome analysis to elucidate genetic features associated with the biofilm lifestyle. We furthermore determined the motility and studied biofilm formation on stainless steel using a static mono-species biofilm model mimicking the meat processing environment. The biomass and the EPS components carbohydrates, proteins and extracellular DNA (eDNA) of the biofilms were investigated after seven days at 10 °C.Whole-genome analysis of the isolates revealed that all strains except the Kocuria salsicia BF1 isolate, harboured biofilm associated genes, including genes for matrix production and motility. Genes involved in cellulose metabolism (present in 82% of the eleven strains) and twitching motility (present in 45%) were most frequently found. The capacity for twitching was confirmed using plate assays for all strains except Lactococcus piscium BF1, which showed the lowest motility behaviour.Differences in biofilm forming abilities could be demonstrated. The bacterial load ranged from 5.4 log CFU/cm2 (Psychrobacter sp. isolate) to 8.7 log CFU/cm2 (Microbacterium sp. isolate). The amount of the matrix components varied between isolates. In the biofilm of six strains we detected all three matrix components at different levels (carbohydrates, proteins and eDNA), in two only carbohydrates and eDNA, and in three only carbohydrates. Carbohydrates were detected in biofilms of all strains ranging from 0.5 to 4.3 μg glucose equivalents/cm2. Overall, the Microbacterium sp. strain showed the highest biofilm forming ability with high bacterial load (8.7 log CFU/cm2) and high amounts of carbohydrates (2.2 μg glucose equivalents/cm2), proteins (present in all experiments) and eDNA (549 ng/cm2). In contrast, Brochothrix thermosphacta was a weak biofilm former, showing low bacterial load and low levels of carbohydrates in the matrix (6.2 log CFU/cm2 and 0.5 μg glucose equivalents/cm2).This study contributes to our understanding of the biofilm forming ability of bacteria highly abundant in the meat processing environment, which is crucial to develop strategies to prevent and reduce biofilm formation in the food producing environment.

Daily intake of a homeopathic agent by dogs modulates white cell defenses and reduces bacterial counts in feces

Motivated by conventional medicines' ineffectiveness and the appearance of bacterial resistance, homeopathic medicines are being increasingly demanded by the veterinary market. Dog feces contain high bacterial and pathogenic loads, which can cause diseases in animals and facilitate zoonotic transmission. Adequate animal immunity contributes to the elimination of potential pathogens. This work's objective was to evaluate the effects of using a homeopathic medication on blood cell counts, serum protein levels, and fecal bacterial counts in dogs. Two groups were used, each including five 19-month-old Beagle dogs. The homeopathic product Orgainfecto® was sprayed on the two daily meals in the treated group (T), at 0.5 mL/animal/day for 60 days; the group that did not receive the homeopathic was considered the control (C), who were fed only the vehicle used in the production of the homeopathic as a placebo. On days 1, 30, and 60, individual stool samples were collected for bacterial counts in the stool, blood samples for blood counts, and serum for biochemical tests. Total bacterial counts in feces were lower in group T on days 30 and 60 of the experiment, while total coliforms and E coli. were lower in this group on day 60. Total leukocyte counts were lower on day 60 in group T, unlike the neutrophil count, higher in group T on day 30, and eosinophils on day 60. However, the lymphocyte count was lower in group T on days 30 and 60. There was an increase in globulin and total protein in group T on day 60. We conclude that the tested homeopathic causes neutrophils and eosinophils' stimulation and increases globulins levels even with reduced lymphocytes. The daily consumption of homeopathic by dogs decreases the intestinal bacterial load, resulting in less environmental contamination and animal and human colibacillosis risks.

Chronically Hypertensive Transgenic Mice Expressing Human AT1R Haplotype‐I Exhibit Increased Susceptibility To Francisella Tularensis

Angiotensin receptor type 1 (AT1R), a G-protein coupled receptor mediates the effect of angiotensin-II and contributes to the pathophysiological consequences of metabolic disorders leading to vascular remodeling, hypertension, and end-organ damage. Genetic variations that increase human AT1R (hAT1R) expression can cause above pathological outcomes due to renin-angiotensin system overactivity. Previously we have shown that transgenic (TG) mice containing haplotype-I (Hap-I, hypertensive genotype) of human AT1R gene are more prone to develop the metabolic syndrome (MetS) related disorders as compared to the TG mice containing haplotype-II (Hap-II, normotensive genotype). We have also shown that as compared to Hap-II, the aged Hap-I TG mice overexpress the hAT1R gene resulting in an increase in blood pressure, inflammatory molecules, and renal dysfunction. Aging together with an increased risk of hypertension, can affect multiple organ systems in a complex manner, including susceptibility to various infections. The current study, therefore, was designed to examine the potential effect of aging and associated MetS disorders in our hAT1R containing TG mice model, in response to the infection by Francisella tularensis live vaccine strain (LVS) inhalation. Our results show that Hap-I TG mice have a significantly high mortality rate two weeks post-infection as compared to the Hap-II animals. Histochemical analysis of lung tissues from adult and aged animals show a comparatively elevated pathology in mice containing Hap-I of hAT1R. The lung tissue and plasma from Hap-I TG mice also show a relatively higher bacterial load five days post-infection. Preliminary RT-PCR experiments show increased inflammatory markers like IL-6, TGF-β, TNF-α, CRP and redox markers like NOX1, NOX4 in lung tissues of Hap-I TG mice. These studies suggest that haplotype dependent over-expression of hAT1R gene, leads to an enhanced mortality and lung pathology to F. tularensis LVS infection, which gets aggravated in aged animals. Clinically, our results may help in exploring the role of AT1R induced hypertension in pulmonary infections.

Dynamic Pneumococcal Genetic Adaptations Support Bacterial Growth and Inflammation during Coinfection with Influenza.

ABSTRACTStreptococcus pneumoniae (pneumococcus) is one of the primary bacterial pathogens that complicates influenza virus infections. These bacterial coinfections increase influenza-associated morbidity and mortality through a number of immunological and viral-mediated mechanisms, but the specific bacterial genes that contribute to postinfluenza pathogenicity are not known. Here, we used genome-wide transposon mutagenesis (Tn-Seq) to reveal bacterial genes that confer improved fitness in influenza virus-infected hosts. The majority of the 32 genes identified are involved in bacterial metabolism, including nucleotide biosynthesis, amino acid biosynthesis, protein translation, and membrane transport. We generated mutants with single-gene deletions (SGD) of five of the genes identified, SPD1414, SPD2047 (cbiO1), SPD0058 (purD), SPD1098, and SPD0822 (proB), to investigate their effects on in vivo fitness, disease severity, and host immune responses. The growth of the SGD mutants was slightly attenuated in vitro and in vivo, but each still grew to high titers in the lungs of mock- and influenza virus-infected hosts. Despite high bacterial loads, mortality was significantly reduced or delayed with all SGD mutants. Time-dependent reductions in pulmonary neutrophils, inflammatory macrophages, and select proinflammatory cytokines and chemokines were also observed. Immunohistochemical staining further revealed altered neutrophil distribution with reduced degeneration in the lungs of influenza virus-SGD mutant-coinfected animals. These studies demonstrate a critical role for specific bacterial genes and for bacterial metabolism in driving virulence and modulating immune function during influenza-associated bacterial pneumonia.

PRAK Promotes the Pathogen Clearance by Macrophage Through Regulating Autophagy and Inflammasome Activation

The p38 regulated/activated protein kinase (PRAK) is a protein kinase downstream of p38MAPK. The present study investigated its function in the macrophage. Myeloid-specific deletion of Prak resulted in a significant reduction in F4/80+CD11b+ peritoneal macrophages with decreased expression of MHC-II and CD80. Upon infection with Listeria monocytogenes, Prak-deficient mice demonstrated an increased mortality, which was accompanied by a higher bacterial load in multiple tissues and elevated levels of proinflammatory cytokines in the serum. While the Prak-deficient macrophage showed similar potency in phagocytosis assays, its bactericidal activity was severely impaired. Moreover, Prak deficiency was associated with defects in ROS production, inflammasome activation as well as autophagy induction. Therefore, PRAK critically contributes to the clearance of intracellular pathogens by affecting multiple aspects of the macrophage function.

Evaluation of Bacterial Contamination of Beef Carcasses in Namwala and Lusaka Districts of Zambia

Abattoirs have been purported to be ideal areas were possible microbial contamination of meat products is likely to occur. Food of animal origin, mainly beef, has been identified as a source of dietary protein for humans albeit it being a source of food-borne diseases including zoonoses. This study was carried out to evaluate bacterial contamination and the risk factors associated with contamination of beef carcasses during processing. A total of four abattoirs were sampled within three months with one in Namwala and three in Lusaka districts. A total of 314 beef carcass surface swabs were obtained from the neck region by swabbing the carcasses, immediately after evisceration and after washing. Results The results of mean total viable counts (TVC) of carcass contamination were enumerated as the mean log from 4.7 Log10 cfu/cm2 in an abattoir where Hazard Analysis and Critical Control Points (HACCP) was practiced to 5.8 Log10 cfu/cm2 without HACCP. Bivariate analysis showed a significant difference in carcass contamination when town abattoirs (Lusaka) were compared with rural ones (Namwala); χ2 = 43.87, P < 0.0001. Multiple logistic regression analysis identified poor hygiene practices, the absence of antemortem inspection, and lack of Hazard Analysis and Critical Control Points (HACCP) implementation as significant factors associated with carcass contamination. Conclusion A high microbial load as determined by the Total Viable Count is an indicator that beef is being produced under poor abattoir hygiene conditions. Therefore, beef carcasses with high bacterial loads are potential sources of foodborne pathogens leading to foodborne disease and hence there is need for advocating for good hygiene practices in the abattoirs.

Effects of NF-kB Signaling Inhibitors on Bed Bug Resistance to Orally Provisioned Entomopathogenic Bacteria.

Simple SummaryBed bugs are prolific insect pests across the globe. Chemical control methods are failing at an increasing rate, creating a need for alternative methods. While the use of microbial agents for biological control of insects has had significant success against many pests and holds great promise, research in this area has only recently begun to be considered for bed bugs. Here, we show that chemical inhibition of pathways involved in bed bug immunity can boost mortality during infection with orally provisioned entomopathogenic bacteria by reducing the ability of bed bugs to clear bacterial infection. Our findings suggest that reducing resistance to infection through inhibition of immune signaling may be a viable strategy for biological control of bed bugs. From an applied perspective, this work is a critical step towards the optimization of ingestible biological control formulations.Bed bugs are globally important pests and there is an ongoing need for the development and improvement of bed bug control tools. Though promising against other insect pests, the exploration of biological methods for bed bug control is limited. Previously, we identified several species of bacteria that have entomopathogenic effects against bed bugs when ingested. We also described the conservation of several antibacterial responses in bed bugs, including the expression of immune effector genes regulated by NF-kB transcription factors through the Toll and immune deficiency (IMD) signaling pathways. Accordingly, we predicted that chemical inhibition of NF-kB signaling could reduce bed bug resistance to orally provisioned entomopathogenic bacteria, potentially improving their effectiveness as biological control agents. In the present study, we administered four small molecule inhibitors of NF-kB signaling (BMS345541, IKK16, IMD0354, Takinib) to bed bugs by feeding them in a blood meal. We then quantified basal mortality and mortality in response to oral infection with two different entomopathogenic bacteria (Pseudomonas entomophila and Bacillus thuringiensis israelensis). None of the NF-kB signaling inhibitors tested increased mortality above control levels when administered alone, suggesting a lack of direct toxicity. However, one inhibitor (IKK16) significantly enhanced the rate of mortality from oral infection with P. entomophila. Enhanced mortality was independent of direct effects of IKK16 on P. entomophila growth in vitro but was associated with higher bacterial loads in vivo (i.e., reduced resistance). Together, these results provide new insight into the regulation of the bed bug immune system and suggest that administration of entomopathogens in combination with inhibition of immune signaling pathways to reduce infection resistance may be effective for biological control of bed bugs.

Potential Molds and Bacterial Species Associated with Deterioration of Sweet potatoes in Kebbi State, Northern Nigeria

The present study aimed to assess the types of microorganisms associated with two different varieties of sweet potatoes yellow skin with white flesh and white skin with yellow flesh cultivated in Kebbi. The analysis of microorganisms was done using the pour plate method. Two L.G.A and three collection points from each L.G.A were selected and sampled. Eight bacteria and five fungal species were isolated and identified from the two varieties of sweet potatoes. Bacterial species identified were; Staphylococcus aureus, Salmonella spp., E. coli, Bacillus spp., Pseudomonas spp., L. monocytogens, Klebsiella spp., and Erwinia spp., while fungal species isolates are Aspergillus spp., Mucor recemosus, Rhizopus spp., Fusarium oxysporium, and Penicillum spp., in both samples. Results revealed that yellow skin with white flesh sweet potato from Gumben kure had the highest bacterial load 7.2 x 104 cfu/ml. The lowest bacterial load obtained from yellow skin with white-fleshed variety in Gwadangwaji 3.2 x 104cfu/ml. The highest fungal load spore in yellow skin with white-fleshed sweet potato 2.0 x 104sfu/ml was obtained from Kardi and the lowest fungal spores observed in Gulumbe white skin with yellow flesh variety 4.0 x 104sfu/ml. The pathogen city test results revealed that all microorganisms isolated in this research showed varying degrees of tubers rot with Rhizopus spp., had highest and bacterial ranged from 4.0 to 2.0 depths (cm). In conclusion, the presence of these microorganisms isolated and identified from two varieties of sweet potato showed that these species are responsible for these tubers' spoilage in the study area

Diagnostic Accuracy of Point-of-Care Fluorescence Imaging for the Detection of Bacterial Burden in Wounds: Results from the 350-Patient Fluorescence Imaging Assessment and Guidance Trial.

Objective: High bacterial load contributes to chronicity of wounds and is diagnosed based on assessment of clinical signs and symptoms (CSS) of infection, but these characteristics are poor predictors of bacterial burden. Point-of-care fluorescence imaging (FL) MolecuLight i:X can improve identification of wounds with high bacterial burden (>104 colony-forming unit [CFU]/g). FL detects bacteria, whether planktonic or in biofilm, but does not distinguish between the two. In this study, diagnostic accuracy of FL was compared to CSS during routine wound assessment. Postassessment, clinicians were surveyed to assess impact of FL on treatment plan.Approach: A prospective multicenter controlled study was conducted by 20 study clinicians from 14 outpatient advanced wound care centers across the United States. Wounds underwent assessment for CSS followed by FL. Biopsies were collected to confirm total bacterial load. Three hundred fifty patients completed the study (138 diabetic foot ulcers, 106 venous leg ulcers, 60 surgical sites, 22 pressure ulcers, and 24 others).Results: Around 287/350 wounds (82%) had bacterial loads >104 CFU/g, and CSS missed detection of 85% of these wounds. FL significantly increased detection of bacteria (>104 CFU/g) by fourfold, and this was consistent across wound types (p < 0.001). Specificity of CSS+FL remained comparably high to CSS (p = 1.0). FL information modified treatment plans (69% of wounds), influenced wound bed preparation (85%), and improved overall patient care (90%) as reported by study clinicians.Innovation: This novel noncontact, handheld FL device provides immediate, objective information on presence, location, and load of bacteria at point of care.Conclusion: Use of FL facilitates adherence to clinical guidelines recommending prompt detection and removal of bacterial burden to reduce wound infection and facilitate healing.

Environmental surface sampling for qualitative &amp; quantitative detection of microbial burden in high risk areas of three hospitals in Dhaka city

Background and objectives: Acquiring infection from intensive care units &amp; operation theatres is considered as a significant public health problem around the world. Microbial burden may vary across different ICUs and OTs, albeit these sectors remain underexplored especially in resource poor country. Purpose of the study was qualitative and quantitative assessment of microbial burden in ICUs and OTs’ environmental surfaces of three tertiary care hospitals in Dhaka city.&#x0D; Materials and methods: The study was conducted in the department of Microbiology, BIRDEM General Hospital. A total 232 environmental surface swab samples &amp; 86 hand &amp; nasal swab samples of ICU staffs were collected from the selected three hospitals. The samples were processed according to standard operating procedures.&#x0D; Results: Highest bacterial load from inanimate surface was found on sinks (155 CFU/cm²), ICU bedrails (7.56 ± 0.76 CFU/cm²) and OT sandals (66 CFU/cm²). Pathogenic isolates were found more in ICUs &amp; non-pathogenic isolates were found more in OTs. Among the non-pathogens, Micrococcus spp. (37.8%) and Bacillus spp. (19.8%) were found from OTs. Among the pathogens, Acinetobacter spp. was predominant (21.2%) followed by Pseudomonas spp. (19.2%) in the ICUs. Overall cleanliness &amp; hygiene status of Hospital ‘A’ &amp; ‘C’ were found unacceptable whereas Hospital ‘B’ was found marginally bearable/tolerable.&#x0D; Conclusion: It could be inferred from the study that health care workers and environmental surface contaminations with MDR pathogens are a definitive risk factor for the indoor patients. Routine sampling to assess bioburden in high risk areas of hospital should be done regularly for identification &amp; correction of the weakness of ongoing infection control protocol.&#x0D; Bangladesh J Med Microbiol 2021; 15 (1): 15-25

Outcomes of albino Mice Liver Infected with Contaminated Camel Milk

Background: Camel milk is an excellent source of nutrients and has medicinal importance for human in many countries all over the world especially in nomadic societies of Arab countries. Staphylococcus aureus (S. aureus) is instinctively present in milk and dairy products, and associated with many outbreaks. Milk is a good substrate for S. aureus rise and toxin production. When transmitted to human body this pathogen may affect skin, brain, kidney, liver and several other vital organs. Therefore, the pathological effects of S. aureus have been the focus of several recent research works.Aim: The present investigation was designed to better characterize the histopathological outcomes of contaminated raw camel milk with S. aureus on the mice liver. Materials and methods: S. aureus were isolated from specimens of lactating she-camels (Camelus dromedarius), weighing 300-540 kg, in Libya and identified using microbiological and molecular techniques. Twenty healthy male Swiss albino mice, weighing 22-25 gm, were divided into two groups; Group I (control) and Group II (orally injected mice with a single dose of aqueous solutions of the isolated bacteria at a concentration of 5x108/0.1ml). Animals sacrificed after three days of oral feeding with milk containing high bacterial load and their livers were dissected out for macro- and microscopic inspection.Results: Our study reported that infection with contaminated milk causes outer liquid-filled liver abscesses. Furthermore, various histopathological changes could be detected. Conclusion: This study may highlight the potential risk of consuming raw she-camel milk, especially upon lack of strict hygienic and preventative measures to avoid the presence of S. aureus in milk.

In vitro and in vivo antibacterial properties of peptide AMC-109 impregnated wound dressings and gels.

Synthetic mimics of antimicrobial peptides (AMPs) is a promising class of molecules for a variety of antimicrobial applications. Several hurdles must be passed before effective systemic infection therapies with AMPs can be achieved, but the path to effective topical treatment of skin, nail, and soft tissue infections appears less challenging to navigate. Skin and soft tissue infection is closely coupled to the emergence of antibiotic resistance and represents a major burden to the healthcare system. The present study evaluates the promising synthetic cationic AMP mimic, AMC-109, for treatment of skin infections in vivo. The compound is evaluated both in impregnated cotton wound dressings and in a gel formulation against skin infections caused by Staphylococcus aureus and methicillin resistant S. aureus. Both the ability to prevent colonization and formation of an infection, as well as eradicate an ongoing infection in vivo with a high bacterial load, were evaluated. The present work demonstrates that AMC-109 displays a significantly higher antibacterial activity with up to a seven-log reduction in bacterial loads compared to current clinical standard therapy; Altargo cream (1% retapamulin) and Fucidin cream (2% fusidic acid) in the in vivo wound models. It is thus concluded that AMC-109 represents a promising entry in the development of new and effective remedies for various skin infections.

PD-1 blockade carries perils

Immunotherapy The potentiation of T cell–mediated antitumor responses achieved in multiple types of cancer through inhibition of the programmed death-1 (PD-1) checkpoint pathway has led to suggestions that anti–PD-1 therapy might also boost T cell immunity in chronic infections, including tuberculosis. Kauffman et al. examined the effect of anti–PD-1 antibody treatment on the clinical course of Mycobacterium tuberculosis (Mtb) infection in rhesus macaques. CD8 T cell responses were boosted in monkeys receiving anti–PD-1 infusions, but the stronger CD8 T cell responses were coupled with increases in proinflammatory cytokines, impaired CD4 T cell function, and higher bacterial loads in lung granulomas. These findings in a nonhuman primate model signal that anti–PD-1–based therapy needs to be used cautiously in cancer patients with a history of Mtb exposure. Sci. Immunol. 6 , eabf3861 (2021).

BACTERIAL CONTAMINATIONS OF USED FACE MASKS COLLECTED FROM DIFFERENT CLINICAL SECTIONS IN A UNIVERSITY TEACHING HOSPITAL DURING COVID -19 PANDEMIC CRISES IN NIGERIA

This study was carried out to identify and characterize the bacteria and fungi present in used face masks, obtained from some clinical sections of University Teaching Hospital in Nigeria. The phenotypic; microbiological and biochemical identifications of the microorganisms were determined by the pour plate techniques using, nutrient agar according to established standard protocols. The results recorded a mean total bacterial count that ranged from 1.75 ± 0.12 log10 CFU/ml to 4.36 ± 0.28 log10 CFU/ml. However, the samples collected from the Anatomy section recorded the lowest bacterial count (1.75 ± 0.12 log10 CFU/ml) while samples obtained from the Nursing section had the highest bacterial load (4.36 ± 0.28 log10CFU/ml). The overall screening test showed the presence of three bacterial isolates: Peptococcus, Pseudomonas and Staphylococcus; Consequently, from the total 64 counted bacterial colonies, the frequency of occurrence was predominated by the Pseudomonas 40 (62.5 %) while, mild counts were respectively reported for Staphylococcus and Peptococcus 18 (28.1 %) and 06 (9.40 %). Succinctly, this work has highlighted that, the underlying illnesses such as lung abscesses, asthma, otitis, pneumonia and sinusitis associated with the isolated organisms in this experiment are also directly linked or similar to the symptoms displayed in mild and severe cases of COVID-19 patients.

A Novel N4-Like Bacteriophage Isolated from a Wastewater Source in South India with Activity against Several Multidrug-Resistant Clinical Pseudomonas aeruginosa Isolates.

Multidrug-resistant community-acquired infections caused by the opportunistic human pathogen Pseudomonas aeruginosa are increasingly reported in India and other locations globally. Since this organism is ubiquitous in the environment, samples such as sewage and wastewater are rich reservoirs of P. aeruginosa bacteriophages. In this study, we report the isolation and characterization of a novel P. aeruginosa N4-like lytic bacteriophage, vB_Pae_AM.P2 (AM.P2), from wastewater in Kerala, India. AM.P2 is a double-stranded DNA podovirus that efficiently lyses the model strain, PAO1, at a multiplicity of infection as low as 0.1 phage per bacterium and resistance frequency of 6.59 × 10-4 Synergy in bactericidal activity was observed between AM.P2 and subinhibitory concentrations of the antibiotic ciprofloxacin. Genome sequencing of AM.P2 revealed features similar to those of the N4-like P. aeruginosa phages LUZ7 and KPP21. As judged by two independent assay methods, spot tests and growth inhibition, AM.P2 successfully inhibited the growth of almost 30% of strains from a contemporary collection of multidrug-resistant P. aeruginosa clinical isolates from South India. Thus, AM.P2 may represent an intriguing candidate for inclusion in bacteriophage cocktails developed for various applications, including water decontamination and clinical bacteriophage therapy.IMPORTANCE In India, multidrug resistance determinants are much more abundant in community-associated bacterial pathogens due to the improper treatment of domestic and industrial effluents. In particular, a high bacterial load of the opportunistic pathogen P. aeruginosa in sewage and water bodies in India is well documented. The isolation and characterization of bacteriophages that could target emerging P. aeruginosa strains, representing possible epicenters for community-acquired infections, could serve as a useful alternative tool for various applications, such as phage therapy and environmental treatment. Continuing to supplement the repertoire of broad-spectrum bacteriophages is an essential tool in confronting this problem.

Nondetection of SARS-CoV-2 on high-touch surfaces of public areas next to COVID-19 hospitalization units

We studied the contamination with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the bacterial load of high-touch surfaces located in public areas next to coronavirus disease (COVID-19) hospitalization units. Ninety-two samples were obtained from 46 different high-touch surfaces: 36 sites next to COVID-19 hospitalization units and 10 sites in the cabins of the public elevators. SARS-CoV-2 was not detected at any site, despite high bacterial loads suggested that the studied sites had been frequently touched prior to the sampling.

Microbial Assessment and Sources for Contamination of Unpackaged Fruit Juice Served in Restaurants of Bushenyi-Ishaka Municipality Western Uganda

Introduction: Globally, unpackaged fruit juices are consumed daily as part of our meals or alone. Unpackaged fruit juices are juices usually served in restaurants in cups. In Bushenyi, Ishaka Municipality Uganda, the most commonly served fruit juices in restaurants are mango, passion fruit, pineapple, and watermelon. However, these juices are beneficial to consumers, their safety is of public health concern due to their suitability in supporting bacterial growth. Objective: This study assessed microbial load and sources for contamination of unpackaged fruit juices served in restaurants of Bushenyi, Ishaka Municipality. Methods: A cross-sectional was employed and unpackaged fruit juice samples were collected in a sterile universal specimen container, transported in a cold chain box to the microbiology laboratory immediately for analysis. Total bacterial load, total coliform and a structured questionnaire were used to collect data on sources for contamination. Results: This study found consistent levels of bacterial contamination range between 5.2 - 5.4 log CFU/ml with no significant differences found on day 1 and day 7 and this demonstrated constant levels of contaminants in the study areas. Contamination on day 1 and day 7 was observed in mangoes, passion, pineapples and watermelon with no significance differences. The total coliform count was in the range of 4.9 - 5.3 log CFU/ml and was highest in all juices above the reference acceptable limits. Water as factor for contamination was significant at p < 0.05. The high bacterial load and fecal coliform are attributed to the use of unclean water for juice preparation. This study observed contamination with fecal coliform bacteria to be a public health concern in the study areas and called for intensify health education among juice producers to observe safety steps during juice preparation and storage.

Acute Experimental Barrier Injury Triggers Ulcerative Colitis-Specific Innate Hyperresponsiveness and Ulcerative Colitis-Type Microbiome Changes in Humans.

Background and aimsThe trigger hypothesis opens the possibility of anti-flare initiation therapies by stating that ulcerative colitis (UC) flares originate from inadequate responses to acute mucosal injuries. However, experimental evidence is restricted by a limited use of suitable human models. We thus aimed to investigate the acute mucosal barrier injury responses in humans with and without UC using an experimental injury model.MethodsA standardized mucosal break was inflicted in the sigmoid colon of 19 patients with UC in endoscopic and histological remission and 20 control subjects. Postinjury responses were assessed repeatedly by high-resolution imaging and sampling to perform Geboes scoring, RNA sequencing, and injury niche microbiota 16S ribosomal RNA gene sequencing.ResultsUC patients had more severe endoscopic postinjury inflammation than did control subjects (P < .01), an elevated modified Geboes score (P < .05), a rapid induction of innate response gene sets (P < .05) and antimicrobial peptides (P < .01), and engagement of neutrophils (P < .01). Innate lymphoid cell type 3 (ILC3) markers were increased preinjury (P < .01), and ILC3 activating cytokines were highly induced postinjury, resulting in an increase in ILC3-type cytokine interleukin-17A. Across groups, the postinjury mucosal microbiome had higher bacterial load (P < .0001) and lower α-diversity (P < .05).ConclusionsUC patients in remission respond to mucosal breaks by an innate hyperresponse engaging resident regulatory ILC3s and a subsequent adaptive activation. The postinjury inflammatory bowel disease–like microbiota diversity decrease is irrespective of diagnosis, suggesting that the dysbiosis is secondary to host injury responses. We provide a model for the study of flare initiation in the search for antitrigger-directed therapies.