Investigating the effect of source contamination on eXTP/SFA

Abstract Background Fomites have long been known to play a key role in the spread of disease causing agents. Hospital-associated fomites in particular have been linked with transmission of members of the Enterococci sp which are key human pathogens. Few studies have explored the role non-hospital door handles might play as potential sources of these isolates. This study therefore set out to explore this role. Results A total of hundred toilet and office door handles in a tertiary institution in Rivers State, Nigeria, were sampled using the swab and rinse method. The presence and drug susceptibility of Enterococcus was determined using the selective bile esculin agar (BEA) and standard microbiological methods. Growth on BEA was observed in 71% of cases, with more growth (38/50, 76%) observed from toilet door handles. Only 35% of samples produced the characteristic black pigmentation associated with Enterococcus sp. Six different bacterial groups were identified from this subset with Enterococcus sp. making up only 14% (5/35) of the isolates. All (100%) Enterococci were isolated from toilet door handles. Antibiotic susceptibility testing revealed very high levels of resistance (80–100%) against 75% of the test antibiotics. An analysis of the antibiotic resistance pattern of each isolate revealed 11 unique antibiogram patterns. Only 2 of these patterns were associated with the enterococci, with majority (4/5) exhibiting resistance to Augmentin (AUG), Ceftazidime (CAZ), Ceftriaxone (CTR), Cefuroxime (CRX), Cloxacillin (CXC), Erythromycin (ERY), Gentamicin (GEN), Ofloxacin (OFL) (antibiogram of AUG–CAZ–CRX–CTR–CXC–ERY). None of the enterococci, however, was resistant to vancomycin. Conclusion This study reports low level contamination of door handles by enterococci. Identical antibiogram patterns linked with majority of the enterococci could however point at the occurrence of a single clone perhaps indicating single source contamination. Reports of high levels of ampicillin resistance among these isolates are problematic as ampicillin–gentamicin combination is the treatment of choice for nosocomial enterococci pathogens.

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Straw-Based Biopurification Systems to Remove Ibuprofen, Diclofenac and Triclosan from Wastewaters: Dominant Microbial Communities

Agronomy ◽

10.3390/agronomy11081507 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1507

Author(s):

Laura Delgado-Moreno ◽

Pieter van Dillewijn ◽

Rogelio Nogales ◽

Esperanza Romero

Keyword(s):

Community Structure ◽

Microbial Community ◽

Point Source ◽

Relative Abundance ◽

Alpha Diversity ◽

Microbial Structure ◽

Methyl Triclosan ◽

Source Contamination ◽

Biopurification Systems ◽

Olive Mill

The continued discharge of pharmaceuticals and personal care products (PPCPs) into the environment due to their widespread use and the lack of effective systems for their removal from water is a global problem. In this study, the dissipation of ibuprofen, diclofenac and triclosan added simultaneously in biopurification systems (BPSs) with different compositions and their effect on the microbial community structure was analysed. Three BPSs, constituted by mixtures of soil (S), peat (P), or raw wet olive mill cake (A) or its vermicompost (V) and straw (S) were prepared (SPS, SAS and SVS). Sorption and degradation experiments were carried out. After 84 days of incubation, more than 85% of each PPCP applied had dissipated. Methyl-triclosan was determined to be highest in the SVS biomixture. Biomixtures with lower C/N ratio and higher alpha diversity were the most effective in the removal of PPCPs. Initially, the BPS biomixtures showed a different microbial structure dominated by Proteobacteria, Actinobacteria and Bacteroidetes but after addition of PPCPs, a similar pattern was observed in the relative abundance of the phylum Chloroflexi, the class Sphingobacteriia and the genus Brevundimonas. These biopurification systems can be useful to prevent point source contamination due to the disposal of PPCP-contaminated waters.

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Applying Model for Water Pollution commencing Non-Point Resource Based on Statistical Data in River

Pollution Engineering ◽

10.17762/pe.v51i1.57 ◽

2020 ◽

Vol 51 (1) ◽

pp. 03-04

Author(s):

Leon Kirk

Keyword(s):

Statistical Data ◽

Nonpoint Source ◽

Direct Result ◽

Soil Tests ◽

Soil P ◽

Water Condition ◽

Farmland Soil ◽

Source Contamination ◽

Landscape Geography ◽

Spatial Area

Eutrophication is an overall contamination issue, when the directresource contamination is proficiently unnatural; contamination load from non-point foundation has the expanding extent in the complete burden. The investigation on non-point foundation contamination is a significant perspective in the exploration on water condition contamination. The nonpoint source contamination, highlighted by broad inclusion, dynamic intricacy and troublesome evaluation of precise spatial area and release degree, is a solution and troublesome concern for the investigation of water condition contamination. In this magazine, an improved fare co-efficient strategy is projected to gauge non-point foundation contamination load in watersheds, same thinking about the impacts of precipitation and the decrease of toxin during the time spent vehicle. The measures of downpour and overflow are enormous in soaked years, so the non-point foundation contamination heaps created are huge too in different years, the non-point foundation contamination loads are fewer a direct result of less precipitation in typical water years. Non-point resource contamination factors are investigated, for example, precipitation, land use, landscape, geography and soil P speciation in farmland soil tests in forest soil tests, and in orchardland soil tests.

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Daily Variability of Listeria Contamination Patterns in a Cold-Smoked Salmon Processing Operation

Journal of Food Protection ◽

10.4315/0362-028x-69.9.2123 ◽

2006 ◽

Vol 69 (9) ◽

pp. 2123-2133 ◽

Cited By ~ 26

Author(s):

YUEWEI HU ◽

KEN GALL ◽

ALPHINA HO ◽

RENATA IVANEK ◽

YRJÖ T. GRÖHN ◽

...

Keyword(s):

Environmental Samples ◽

Food Product ◽

Processing Operation ◽

Smoked Salmon ◽

High Prevalence ◽

Chance Events ◽

Source Contamination ◽

Contamination Event ◽

Working Day ◽

Listeria Welshimeri

An understanding of Listeria transmission and contamination patterns in processing environments of ready-to-eat foods is critical for improving control of Listeria monocytogenes. A cold-smoked fish processing operation was the site used to study variability in Listeria contamination in a processing environment associated with a ready-to-eat food product throughout one production week (five consecutive days). Intensive testing was conducted on finished products and environmental samples collected at the beginning, middle, and end of each working day. A total of 20 finished products and 22 to 36 environmental samples were collected at each sampling time, and an additional 12 environmental samples were collected on days 4 and 5. Overall, a total of 782 samples, 300 finished products and 482 environmental samples, were tested. All samples were collected from processing steps after smoking, including skinning, trimming, slicing, staging, and packing. A total of 28 finished and 57 environmental samples (9.3 and 11.8%, respectively) were positive for Listeria spp. (including 1 and 5 samples positive for L. monocytogenes, respectively). DNA sequencing of the sigB gene allowed differentiation of eight Listeria subtypes. Listeria prevalence varied significantly between days, and a high prevalence in both environmental samples and finished products on day 3 was likely associated with a point source contamination event by a single Listeria welshimeri subtype. There were no consistent differences in Listeria prevalence among samples collected from the beginning, middle, and end of the production day, but subtype data often revealed unique contamination patterns for samples collected at different times of a given day. Listeria contamination patterns and prevalences were highly variable between days and within a given day. These findings indicate that chance events play an important role in the contamination of finished products, thus complicating efforts to define Listeria transmission patterns in processing environments associated with ready-to-eat foods.

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Concentrations of pesticide residues in grasses and sedges due to point source contamination and the indications for public health risks, Vikuge, Tanzania

Chemosphere ◽

10.1016/j.chemosphere.2005.03.059 ◽

2005 ◽

Vol 61 (9) ◽

pp. 1293-1298 ◽

Cited By ~ 15

Author(s):

John Andrew Mahugija Marco ◽

Michael A. Kishimba

Keyword(s):

Public Health ◽

Point Source ◽

Health Risks ◽

Pesticide Residues ◽

Public Health Risks ◽

Source Contamination

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Stochastic Assessment of Nonpoint Source Contamination: Joint Impact of Aquifer Heterogeneity and Well Characteristics on Management Metrics

Water Resources Research ◽

10.1029/2018wr024230 ◽

2019 ◽

Vol 55 (8) ◽

pp. 6773-6794 ◽

Cited By ~ 9

Author(s):

Christopher Vincent Henri ◽

Thomas Harter

Keyword(s):

Nonpoint Source ◽

Aquifer Heterogeneity ◽

Source Contamination

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Prevalence and genetic diversity of Salmonella spp. in a river in a tropical environment in Mexico

Journal of Water and Health ◽

10.2166/wh.2014.051 ◽

2014 ◽

Vol 12 (4) ◽

pp. 874-884 ◽

Cited By ~ 13

Author(s):

Maribel Jiménez ◽

Jaime Martinez-Urtaza ◽

Maria Xose Rodriguez-Alvarez ◽

Josefina Leon-Felix ◽

Cristobal Chaidez

Keyword(s):

Genetic Diversity ◽

Disease Transmission ◽

Generalized Additive Models ◽

Environmental Parameters ◽

Additive Models ◽

Salmonella Spp ◽

Tropical Regions ◽

Northwestern Region ◽

Source Contamination ◽

Human Infections

The capability of Salmonella to survive outside a host is especially relevant in tropical regions, where the environmental conditions could be more suitable for its long-term persistence. This study investigated the prevalence and genetic diversity of salmonellae within rivers of the Culiacan Valley in the northwestern region of Mexico. From July 2008 to June 2009, a total of 138 water samples were evaluated for the presence of Salmonella spp.; additionally, its association with environmental parameters was determined using Generalized Additive Models (GAMs). Salmonella spp. were isolated from 111 (80.4%) samples without any statistical influence on the environmental parameters investigated, according to the GAM analysis. Twenty-four serotypes were identified; the most frequently isolated serotypes were Salmonella Oranienburg (25%), Salmonella Saintpaul (9%) and Salmonella Minnesota (6%). Diverse genetic variants of Salmonella Oranienburg were found distributed across the valley with no distinctive geographical or temporal patterns. The high persistence of Salmonella spp. and the lack of differentiation of types found along the river basins suggest the existence of non-point source contamination. Furthermore, the discrepancy between the prevailing serotypes in human infections and those identified in this study denotes a limited influence of these aquatic environments in bacterial dissemination and disease transmission.

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