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1.
Environ Manage ; 68(1): 117-125, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33914093

RESUMEN

Suppression of established populations of invasive alien species can be a complex and expensive process, which is frequently unsuccessful. The Asian clam, Corbicula fluminea (Müller, 1774), is considered a high impact invader that can adversely alter freshwater ecosystems and decrease their socioeconomic value. To date, C. fluminea continues to spread and persist within freshwater environments worldwide, despite repeated management attempts to prevent dispersal and suppress established populations. As extensive C. fluminea beds can often become exposed during low-water conditions, the direct application of hot or cold thermal shock treatments has been proposed as suitable mechanism for their control. Further, mechanical substrate disturbance may enhance the efficacy of thermal shock treatments by facilitating exposures to multiple layers of buried clams. In the present study, we advanced these methods by assessing combined applications of both hot and cold thermal shock treatments for control of C. fluminea, using steam spray (≥100 °C; 350 kPa), low- or high-intensity open-flame burns (~1000 °C) and dry ice (-78 °C). In a direct comparison of raking combined with hot thermal shock applications, both steam and high-intensity open-flame treatments tended to be most effective, especially following multiple applications. In addition, when hot thermal treatments are followed by a final cold shock (i.e. dry ice), steam treatments tended to be most effective. Further, when dry ice was applied either alone or prior to an application of a hot shock treatment, substantial if not complete C. fluminea mortality was observed. Overall, this study demonstrated that combined applications of hot and cold thermal shock treatments, applied following the disruption of the substrate, can substantially increase C. fluminea mortality compared to separate hot or cold treatments.


Asunto(s)
Corbicula , Contaminantes Químicos del Agua , Animales , Ecosistema , Especies Introducidas , Humo , Agua
2.
Glob Chang Biol ; 26(11): 6235-6250, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32851731

RESUMEN

Prioritizing the management of invasive alien species (IAS) is of global importance and within Europe integral to the EU IAS regulation. To prioritize management effectively, the risks posed by IAS need to be assessed, but so too does the feasibility of their management. While the risk of IAS to the EU has been assessed, the feasibility of management has not. We assessed the feasibility of eradicating 60 new (not yet established) and 35 emerging (established with limited distribution) species that pose a threat to the EU, as identified by horizon scanning. The assessment was carried out by 34 experts in invasion management from across Europe, applying the Non-Native Risk Management scheme to defined invasion scenarios and eradication strategies for each species, assessing the feasibility of eradication using seven key risk management criteria. Management priorities were identified by combining scores for risk (derived from horizon scanning) and feasibility of eradication. The results show eradication feasibility score and risk score were not correlated, indicating that risk management criteria evaluate different information than risk assessment. In all, 17 new species were identified as particularly high priorities for eradication should they establish in the future, whereas 14 emerging species were identified as priorities for eradication now. A number of species considered highest priority for eradication were terrestrial vertebrates, a group that has been the focus of a number of eradication attempts in Europe. However, eradication priorities also included a diverse range of other taxa (plants, invertebrates and fish) suggesting there is scope to broaden the taxonomic range of attempted eradication in Europe. We demonstrate that broad scale structured assessments of management feasibility can help prioritize IAS for management. Such frameworks are needed to support evidence-based decision-making.


Asunto(s)
Ecosistema , Especies Introducidas , Animales , Europa (Continente) , Estudios de Factibilidad , Vertebrados
3.
J Environ Manage ; 266: 110519, 2020 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-32392135

RESUMEN

The most commonly used method for measuring vegetation cover is visual estimation, which is highly subjective, potentially leading to measurement errors. This poses serious implications to the assessment and continued management of plant species cover, for example in the control of invasive plant species. Morphological analysis of digital imagery has, to date, been primarily applied in the classification of landscape features. Our novel application of morphological image analysis provides an objective method for detection and accurate cover assessment of an invasive alien plant species (IAS), giving reduced measurement errors when compared to visual estimation. Importantly, this method is entirely based on free software. Guidos Toolbox is a collection of generic raster image processing routines, including Morphological Spatial Pattern Analysis (MSPA), which classifies and quantifies features according to shape. MSPA was employed in this study to detect and quantify cover of invasive Petasites pyrenaicus (Winter heliotrope) in digital images of 1 m × 1 m plots. Its efficacy was compared to that of two other methods- GIS Digitisation (used as an accurate baseline) and Visual Estimation (standard method). We tested the limit of MSPA usability on images of varying complexity, i.e. "simple", intermediate" or "complex", depending on presence/absence of other vascular plant species and the species richness of plot. Our results show good agreement between all three methods. MSPA measurement of P. pyrenaicus cover was most closely aligned with the GIS Digitisation (concordance correlation coefficients of 0.966). Visual Estimation was less closely aligned with GIS Digitisation (concordance correlation coefficients of 0.888). However, image complexity resulted in differing levels of agreement; with the closest agreement being achieved between MSPA and GIS Digitisation when used on images of lower and higher complexity. MSPA consistently provides higher accuracy and precision for P. pyrenaicus cover measurement than the standard Visual Estimation method. Our methodology is applicable to a range of focal vegetation species, both herbaceous and graminoid. Future application of MSPA for larger-scale surveying and monitoring via remote sensing is discussed, potentially reducing resource demands and increasing cover measurement consistency and accuracy. We recommend this method forms part of vegetation management toolkits for not only environmental managers, but for anyone concerned with plant cover assessment, from agricultural systems to sustainable resource use.


Asunto(s)
Especies Introducidas , Tecnología de Sensores Remotos , Agricultura , Monitoreo del Ambiente , Plantas , Programas Informáticos
4.
Environ Manage ; 66(4): 654-663, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32627081

RESUMEN

Control strategies for established populations of invasive alien species can be costly and complex endeavours, which are frequently unsuccessful. Therefore, rapid-reaction techniques that are capable of maximising efficacy whilst minimising environmental damage are urgently required. The Asian clam (Corbicula fluminea Müller, 1774), and the zebra mussel (Dreissena polymorpha Pallas, 1771), are invaders capable of adversely affecting the functioning and biodiversity of freshwater ecosystems. Despite efforts to implement substantial population-control measures, both species continue to spread and persist within freshwater environments. As bivalve beds often become exposed during low-water conditions, this study examined the efficacy of steam-spray (≥100 °C, 350 kPa) and open-flame burn treatments (~1000 °C) to kill exposed individuals. Direct steam exposure lasting for 5 min caused 100% mortality of C. fluminea buried at a depth of 3 cm. Further, combined rake and thermal shock treatments, whereby the substrate is disturbed between each application of either a steam or open flame, caused 100% mortality of C. fluminea specimens residing within a 4-cm deep substrate patch, following three consecutive treatment applications. However, deeper 8-cm patches and water-saturated substrate reduced maximum bivalve species mortality rates to 77% and 70%, respectively. Finally, 100% of D. polymorpha specimens were killed following exposure to steam and open-flame treatments lasting for 30 s and 5 s, respectively. Overall, our results confirm the efficacy of thermal shock treatments as a potential tool for substantial control of low-water-exposed bivalves. Although promising, our results require validation through upscaling to field application, with consideration of other substrate types, increased substrate depth, greater bivalve densities, non-target and long-term treatment effects.


Asunto(s)
Corbicula , Dreissena , Contaminantes Químicos del Agua , Animales , Ecosistema , Regulación de la Población , Vapor
5.
Brain Behav Immun ; 74: 49-67, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-29548992

RESUMEN

Chronic pain can develop in response to conditions such as inflammatory arthritis. The central mechanisms underlying the development and maintenance of chronic pain in humans are not well elucidated although there is evidence for a role of microglia and astrocytes. However in pre-clinical models of pain, including models of inflammatory arthritis, there is a wealth of evidence indicating roles for pathological glial reactivity within the CNS. In the spinal dorsal horn of rats with painful inflammatory arthritis we found both a significant increase in CD11b+ microglia-like cells and GFAP+ astrocytes associated with blood vessels, and the number of activated blood vessels expressing the adhesion molecule ICAM-1, indicating potential glio-vascular activation. Using pharmacological interventions targeting VEGFR2 in arthritic rats, to inhibit endothelial cell activation, the number of dorsal horn ICAM-1+ blood vessels, CD11b+ microglia and the development of secondary mechanical allodynia, an indicator of central sensitization, were all prevented. Targeting endothelial VEGFR2 by inducible Tie2-specific VEGFR2 knock-out also prevented secondary allodynia in mice and glio-vascular activation in the dorsal horn in response to inflammatory arthritis. Inhibition of VEGFR2 in vitro significantly blocked ICAM-1-dependent monocyte adhesion to brain microvascular endothelial cells, when stimulated with inflammatory mediators TNF-α and VEGF-A165a. Taken together our findings suggest that a novel VEGFR2-mediated spinal cord glio-vascular mechanism may promote peripheral CD11b+ circulating cell transmigration into the CNS parenchyma and contribute to the development of chronic pain in inflammatory arthritis. We hypothesise that preventing this glio-vascular activation and circulating cell translocation into the spinal cord could be a new therapeutic strategy for pain caused by rheumatoid arthritis.


Asunto(s)
Endotelio/fisiología , Dolor/fisiopatología , Receptor 2 de Factores de Crecimiento Endotelial Vascular/fisiología , Animales , Artritis/inmunología , Artritis/fisiopatología , Astrocitos/metabolismo , Dolor Crónico/complicaciones , Células Endoteliales/metabolismo , Hiperalgesia/tratamiento farmacológico , Inflamación/fisiopatología , Masculino , Ratones , Ratones Transgénicos , Microglía/metabolismo , Neuralgia/metabolismo , Proyectos Piloto , Ratas , Ratas Wistar , Médula Espinal/metabolismo , Asta Dorsal de la Médula Espinal/metabolismo , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo
6.
Exp Parasitol ; 151-152: 14-20, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25662435

RESUMEN

While a large number of laboratory methods for the detection of Cryptosporidium oocysts in faecal samples are now available, their efficacy for identifying asymptomatic cases of cryptosporidiosis is poorly understood. This study was carried out to determine a reliable screening test for epidemiological studies in livestock. In addition, three molecular tests were compared to identify Cryptosporidium species responsible for the infection in cattle, sheep and horses. A variety of diagnostic tests including microscopic (Kinyoun's staining), immunological (Direct Fluorescence Antibody tests or DFAT), enzyme-linked immunosorbent assay (ELISA), and molecular methods (nested PCR) were compared to assess their ability to detect Cryptosporidium in cattle, horse and sheep faecal samples. The results indicate that the sensitivity and specificity of each test is highly dependent on the input samples; while Kinyoun's and DFAT proved to be reliable screening tools for cattle samples, DFAT and PCR analysis (targeted at the 18S rRNA gene fragment) were more sensitive for screening sheep and horse samples. Finally different PCR primer sets targetedat the same region resulted in the preferential amplification of certain Cryptosporidium species when multiple species were present in the sample. Therefore, for identification of Cryptosporidium spp. in the event of asymptomatic cryptosporidiosis, the combination of different 18S rRNA nested PCR primer sets is recommended for further epidemiological applications and also tracking the sources of infection.


Asunto(s)
Enfermedades de los Bovinos/diagnóstico , Criptosporidiosis/diagnóstico , Cryptosporidium/aislamiento & purificación , Enfermedades de los Caballos/diagnóstico , Enfermedades de las Ovejas/diagnóstico , Animales , Secuencia de Bases , Bovinos , Enfermedades de los Bovinos/parasitología , Cryptosporidium/genética , Cryptosporidium/inmunología , ADN Protozoario/química , ADN Protozoario/aislamiento & purificación , Ensayo de Inmunoadsorción Enzimática/veterinaria , Heces/parasitología , Técnica del Anticuerpo Fluorescente Directa/veterinaria , Enfermedades de los Caballos/parasitología , Caballos , Tamizaje Masivo/métodos , Tamizaje Masivo/veterinaria , Oocistos , Reacción en Cadena de la Polimerasa/métodos , Reacción en Cadena de la Polimerasa/veterinaria , ARN Ribosómico 18S/genética , Sensibilidad y Especificidad , Ovinos , Enfermedades de las Ovejas/parasitología , Coloración y Etiquetado/métodos , Coloración y Etiquetado/veterinaria
7.
Ecotoxicol Environ Saf ; 107: 148-53, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24927392

RESUMEN

Effective, species-specific zebra mussel control is needed urgently for Ireland׳s freshwater bodies, which became infested with non-native zebra mussels in the 1990s. Zequanox®, a newly commercialized product for zebra and quagga mussel control, is composed of dead Pseudomonas fluorescens CL 145A cells. This paper describes ecotoxicology tests on three representative native Irish freshwater species: Anodonta (duck mussel), Chironomus plumosus (non-biting midge), and Austropotamobius pallipes (white-clawed crayfish). The species were exposed to Zequanox in a 72-h static renewal toxicity test at concentrations of 100-750mg active ingredient per liter (mga.i./L). Water quality parameters were measured every 12-24h before and after water and product renewal. After 72h, endpoints were reported as LC10, LC50, and LC100. The LC50 values derived were (1) Anodonta: ≥500mga.i./L (2) C. plumosus: 1075mga.i./L, and (3) A. pallipes: ≥750mga.i./L. These results demonstrate that Zequanox does not negatively affect these organisms at the concentration required for >80percent zebra mussel mortality (150mg a.i/L) and the maximum allowable treatment concentration in the United Sates (200mga.i./L). They also show the overall species-specificity of Zequanox, and support its use in commercial facilities and open waters.


Asunto(s)
Astacoidea , Chironomidae , Dreissena , Especies Introducidas , Plaguicidas/toxicidad , Unionidae , Animales , Ecotoxicología , Agua Dulce , Irlanda , Larva , Control Biológico de Vectores , Pseudomonas fluorescens , Pruebas de Toxicidad , Calidad del Agua
8.
J Water Health ; 10(3): 380-9, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22960482

RESUMEN

Municipal wastewater treatment plants play a crucial role in reducing the microbial and pathogen load of human wastes before the end-products are discharged to surface waters (final effluent) or land spread (biosolids). This study investigated the occurrence frequency of noroviruses, Enterococcus faecalis and Enterococcus faecium in influent, final effluent and biosolids from four secondary wastewater treatment plants in northwestern Ireland (plants A-D) and observed the seasonal and spatial variation of the plant treatment efficiencies in the pathogen removals. It was noted that norovirus genogroup II was more resistant to the treatment processes than the norovirus genogroup I and other active viral particles, especially those in the discharge effluents. The percolating biofilm system at plant D resulted in better effluent quality than in the extended aerated activated sludge systems (plants A and B); primary biosolids produced at plant D may pose a higher health risk to the locals. The spread of norovirus genogroup II into the environment, irrespective of the wastewater treatment process, coincides with its national clinical predominance over norovirus genogroup I. This study provides important evidence that municipal wastewater treatment plants not only achieve pathogen removal but can also be the source of environmental pathogen contamination.


Asunto(s)
Enterococcus faecalis/fisiología , Norovirus/fisiología , Eliminación de Residuos Líquidos/métodos , Microbiología del Agua , Purificación del Agua , Irlanda , Norovirus/clasificación , ARN Viral/clasificación , ARN Viral/genética
9.
Parasitol Res ; 109(3): 595-603, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21360095

RESUMEN

Municipal wastewater treatment plants play a vital role in reducing the microbial load of sewage before the end-products are discharged to surface waters (final effluent) or local environments (biosolids). This study was to investigate the presence of human-virulent microsporidian spores (Enterocytozoon bieneusi, Encephalitozoon intestinalis, and Encephalitozoon hellem) and enterococci during treatment processes at four Irish municipal secondary wastewater treatment plants (plants A-D). Microsporidian abundance was significantly related to seasonal increase in water temperature. Plant A had the least efficient removal of E. intestinalis spores (32%) in wastewater, with almost 100% removal at other plants both in April and July. Some negative removal efficiencies were obtained for E. bieneusi (at plants C and D, -100%) and for E. hellem (at plants A and D, -90% and -50%). In addition, a positive correlation was found between the levels of enterococci and E. bieneusi in July (r (s) = 0.72, P < 0.05). In terms of the dewatered biosolids, a median concentration as high as 32,000 spores/Kg of E. hellem was observed at plant D in July. Plant C sewage sludge contained the lowest microsporidian loadings (E. bieneusi; 450 spores/L and 1,000 spores/L in April and July, respectively). This study highlights the seasonal variation in concentrations of microsporidian spores in the incoming sewage. Spores in final effluents and dewatered biosolids can be the source of human-virulent microsporidian contamination to the local environment. This emphasizes a considerably high public health risk when sewage-derived biosolids are spread during summer months. This study also suggested enterococci as a potential indicator of the presence of microsporidian spores in wastewater, especially for E. bieneusi.


Asunto(s)
Encephalitozoon/aislamiento & purificación , Enterococcus/aislamiento & purificación , Enterocytozoon/aislamiento & purificación , Microbiología Ambiental , Aguas del Alcantarillado/microbiología , Humanos , Irlanda , Estaciones del Año , Esporas Fúngicas/aislamiento & purificación , Temperatura , Purificación del Agua
10.
Parasitol Res ; 106(5): 1103-8, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20145953

RESUMEN

During summer months, samples of marine beach water were tested weekly for human waterborne pathogens in association with high and low bather numbers during weekends and weekdays, respectively. The numbers of bathers on weekends were significantly higher than on weekdays (P < 0.001), and this was associated with a significant (P < 0.04) increase in water turbidity. The proportion of water samples containing Cryptosporidium parvum, Giardia duodenalis, and Enterocytozoon bieneusi was significantly higher (P < 0.03) on weekends than on weekdays, and significantly (P < 0.01) correlated with enterococci counts. The concentration of all three waterborne pathogens was significantly correlated with bather density (P < 0.01). The study demonstrated that: (a) human pathogens were present in beach water on days deemed acceptable for bathing according to fecal bacterial standards; (b) enterococci count was a good indicator for the presence of Cryptosporidium, Giardia, and microsporidian spores in recreational marine beach water; (c) water should be tested for enterococci during times when bather numbers are high; (d) re-suspension of bottom sediments by bathers caused elevated levels of enterococci and waterborne parasites, thus bathers themselves can create a non-point source for water contamination; and (e) exposure to recreational bathing waters can play a role in epidemiology of microsporidiosis. In order to protect public health, it is recommended to: (a) prevent diapered children from entering beach water; (b) introduce bather number limits to recreational areas; (c) advise people with gastroenteritis to avoid bathing; and (d) use showers prior to and after bathing.


Asunto(s)
Playas , Enterobacteriaceae/aislamiento & purificación , Densidad de Población , Agua de Mar/microbiología , Agua de Mar/parasitología , Recuento de Colonia Microbiana , Cryptosporidium parvum/aislamiento & purificación , Enterococcus/aislamiento & purificación , Enterocytozoon/aislamiento & purificación , Giardia/aislamiento & purificación , Humanos
11.
Artículo en Inglés | MEDLINE | ID: mdl-33243758

RESUMEN

BACKGROUND: We aimed to use New Zealand's Anzac Day to test the public health effect of secondary public holidays; and to use weekly hospitalisation counts to identify which dates were more health suitable for a potential new public holiday. METHODS: We conducted a retrospective population cohort study of hospital admissions in New Zealand between 23 April and 27 May 1988-2018. We compared acute and arranged hospitalisation and mortality rates in holiday (Anzac Day Monday to Friday) and non-holiday (Anzac Day Saturday or Sunday) years, for mid-week holidays and long weekends; and measured total weekly average acute and arranged hospitalisation counts. RESULTS: Hospitalisation rates were lower in holiday years than non-holiday years (rate ratio (RR) 0.96, 95% CI 0.95 to 0.96, p<0.001), with fewer arranged admissions (RR 0.93, 95% CI 0.93 to 0.94, p<0.001), but no significant difference for acute admissions (RR 1.00, 95% CI 0.99 to 1.00, p=0.087). Holiday year acute admission rates were lower than non-holiday years for children aged 0-4 years, but higher for adults aged 15-44 years. Holidays reduced arranged admissions most in children and areas of higher socioeconomic deprivation. There was no significant difference for mortality. Average weekly acute hospitalisations were higher than arranged admissions between 10 June and 7 October. CONCLUSION: Secondary holidays do not reduce deaths; or acute hospital admissions except in the holiday week; and may delay elective treatment. However, if New Zealand is to add a new public holiday, it would have least detrimental health effect scheduled between 10 June and 7 October.

12.
Sci Rep ; 10(1): 1919, 2020 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-32024949

RESUMEN

Biosecurity protocols designed to prevent the spread of invasive alien species (IAS) are now an essential aspect of IAS management. However, the effectiveness of various biosecurity treatments requires further exploration. Killer shrimp, Dikerogammarus villosus, a notoriously high impact and ecosystem destabilising invader, has rapidly spread across Europe, and is of concern to invade Northern America. In this study, we examine the effectiveness of three commonly used, broad-spectrum disinfectants to cause mortality of D. villosus: Virasure Aquatic, Virkon Aquatic, and Virkon S. Immersion and spray treatments of 1%, 2% and 4% disinfectant solutions were examined for applications of up to 300 secs immersion and for up to ten consecutive sprays. Furthermore, we assessed the effectiveness of steam (≥100 °C) treatments for up to 120 secs. For all disinfectants, immersion in 1% solutions caused 100% mortality at ≥120 secs. At higher concentrations, shorter immersion times caused complete mortality: 60 and 15 secs for 2% and 4% solutions, respectively. Five sprays of 2% and 4% solutions resulted in 100% mortality, for all disinfectants. Direct steam exposure was highly effective, with complete D. villosus mortality occurring at ≥10 secs. Overall, brief exposure to broad-spectrum disinfectants and direct steam could be used to limit D. villosus spread.


Asunto(s)
Anfípodos/efectos de los fármacos , Descontaminación/métodos , Desinfectantes/toxicidad , Especies Introducidas , Vapor , Animales , Agua Dulce , Peróxidos/toxicidad , Ácidos Sulfúricos/toxicidad , Factores de Tiempo
13.
Appl Environ Microbiol ; 75(13): 4531-8, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19411413

RESUMEN

Constructed subsurface flow (SSF) and free-surface flow (FSF) wetlands are being increasingly implemented worldwide into wastewater treatments in response to the growing need for microbiologically safe reclaimed waters, which is driven by an exponential increase in the human population and limited water resources. Wastewater samples from four SSF and FSF wetlands in northwestern Ireland were tested qualitatively and quantitatively for Cryptosporidium spp., Giardia duodenalis, and human-pathogenic microsporidia, with assessment of their viability. Overall, seven species of human enteropathogens were detected in wetland influents, vegetated areas, and effluents: Cryptosporidium parvum, C. hominis, C. meleagridis, C. muris, G. duodenalis, Encephalitozoon hellem, and Enterocytozoon bieneusi. SSF wetland had the highest pathogen removal rate (i.e., Cryptosporidium, 97.4%; G. duodenalis, 95.4%); however, most of these values for FSF were in the negative area (mean, -84.0%), meaning that more pathogens were discharged by FSF wetlands than were delivered to wetlands with incoming wastewater. We demonstrate here that (i) the composition of human enteropathogens in wastewater entering and leaving SSF and FSF wetlands is highly complex and dynamic, (ii) the removal and inactivation of human-pathogenic microorganisms were significantly higher at the SSF wetland, (iii) FSF wetlands may not always provide sufficient remediation for human enteropathogens, (iv) wildlife can contribute a substantial load of human zoonotic pathogens to wetlands, (v) most of the pathogens discharged by wetlands were viable, (vi) large volumes of wetland effluents can contribute to contamination of surface waters used for recreation and drinking water abstraction and therefore represent a serious public health threat, and (vii) even with the best pathogen removal rates achieved by SSF wetland, the reduction of pathogens was not enough for a safety reuse of the reclaimed water. To our knowledge, this is the first report of C. meleagridis from Ireland.


Asunto(s)
Cryptosporidium parvum/aislamiento & purificación , Agua Dulce/parasitología , Giardia/aislamiento & purificación , Microsporidios/aislamiento & purificación , Purificación del Agua/métodos , Humedales , Animales , Supervivencia Celular , Cryptosporidium parvum/crecimiento & desarrollo , Giardia/crecimiento & desarrollo , Humanos , Irlanda , Microsporidios/crecimiento & desarrollo
14.
Parasitol Res ; 105(3): 689-96, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19396463

RESUMEN

This study investigates the fate of Cryptosporidium parvum and C. hominis oocysts and Giardia duodenalis cysts at four Irish municipal wastewater treatment plants (i.e., Plant A, B, C, and D) that utilize sludge activation or biofilm-coated percolating filter systems for secondary wastewater treatment. The fate of these pathogens through the sewage treatment processes was determined based on their viable transmissive stages, i.e., oocysts for Cryptosporidium and cysts for Giardia. Analysis of final effluent indicated that over 97% of viable oocysts and cysts were eliminated, except at Plant C, which achieved only 64% of oocyst removal. A significant correlation between the removal of oocysts and cysts was found at Plants A, B, and D (R = 0.98, P < 0.05). All sewage sludge samples were positive for C. parvum and C. hominis, and G. duodenalis, with maximum concentrations of 20 oocysts and eight cysts per gram in primary sludge indicating the need for further sludge sanitization treatments. This study provides evidence that C. parvum and C. hominis oocysts and G. duodenalis cysts are present throughout the wastewater processes and in end-products, and can enter the aquatic environment with consequent negative implications for public health.


Asunto(s)
Cryptosporidium/aislamiento & purificación , Giardia/aislamiento & purificación , Aguas del Alcantarillado/parasitología , Microbiología del Agua , Purificación del Agua/métodos , Agua/parasitología , Animales , Irlanda , Oocistos , Recuento de Huevos de Parásitos
15.
Parasitol Res ; 105(2): 423-8, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19343366

RESUMEN

Effluents from a small-scale free-surface flow constructed wetland, used for polishing of secondary treated wastewater, contained significantly higher concentrations of potentially viable Giardia duodenalis cysts and Enterocytozoon bieneusi spores than did wetland influents consisting of secondary treated wastewater. Zoonotic Assemblage A of G. duodenalis cysts was identified in wetland inflows, while Assemblage A and two nonhuman infective Assemblages (i.e., C, and E) were present in wetland effluents. E. bieneusi spores represented genotype K based on DNA sequencing analysis of internal transcribed spacer. The study demonstrated that: (1) free-surface flow small-scale constructed wetlands may not provide sufficient remediation for human zoonotic protozoa and fungi present in secondary treated wastewater; (2) dogs and livestock can substantially contribute human-pathogenic protozoan and fungal microorganisms to engineered vegetated wetland systems; and (3) large volumes of wetland effluents can contribute to contamination of surface waters used for recreation and drinking water abstraction and therefore represent a serious public health threat.


Asunto(s)
Enterocytozoon/aislamiento & purificación , Giardia/aislamiento & purificación , Microbiología del Agua , Agua/parasitología , Humedales , Animales , Análisis por Conglomerados , ADN de Hongos/química , ADN de Hongos/genética , ADN Protozoario/química , ADN Protozoario/genética , ADN Espaciador Ribosómico , Perros , Humanos , ARN Ribosómico 18S/genética , Análisis de Secuencia de ADN
16.
Trans R Soc Trop Med Hyg ; 101(6): 532-3, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17399755

RESUMEN

Demand for high-quality drinking and recreational water rises exponentially owing to global demographic growth in the human population, reinforcing an urgent need for microbiologically safe reclaimed water. However, constructed wetlands, implemented into municipal wastewater treatment, may not provide substantial remediation for human protozoan enteropathogens such as Cryptosporidium, Giardia and human-virulent microsporidia. Improving reclaimed water quality by lowering faecal coliforms is not a sound solution for these pathogens. Current advances in molecular technology can benefit public health in developing and developed countries by changing the conceptual research framework for wastewater-receiving wetlands from 'pathogen removal' to 'pathogen source tracking' efforts.


Asunto(s)
Microbiología del Agua , Purificación del Agua , Agua/parasitología , Humedales , Humanos , Salud Pública , Eliminación de Residuos Líquidos , Agua/normas
17.
Int J Parasitol ; 47(5): 291-296, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28214510

RESUMEN

Invasive species often detrimentally impact native biota, e.g. through predation, but predicting such impacts is difficult due to multiple and perhaps interacting abiotic and biotic context dependencies. Higher mean and peak temperatures, together with parasites, might influence the impact of predatory invasive host species additively, synergistically or antagonistically. Here, we apply the comparative functional response methodology (relationship between resource consumption rate and resource supply) in one experiment and conduct a second scaled-up mesocosm experiment to assess any differential predatory impacts of the freshwater invasive amphipod Gammarus pulex, when uninfected and infected with the acanthocephalan Echinorhynchus truttae, at three temperatures representative of current and future climate. Individual G. pulex showed Type II predatory functional responses. In both experiments, infection was associated with higher maximum feeding rates, which also increased with increasing temperatures. Additionally, infection interacted with higher temperatures to synergistically elevate functional responses and feeding rates. Parasitic infection also generally increased Q10 values. We thus suggest that the differential metabolic responses of the host and parasite to increasing temperatures drives the synergy between infection and temperature, elevating feeding rates and thus enhancing the ecological impact of the invader.


Asunto(s)
Acantocéfalos/fisiología , Anfípodos/parasitología , Especies Introducidas , Acantocéfalos/patogenicidad , Anfípodos/crecimiento & desarrollo , Animales , Cambio Climático , Agua Dulce/parasitología , Interacciones Huésped-Parásitos , Masculino , Irlanda del Norte , Conducta Predatoria , Ríos/parasitología , Temperatura
18.
J Infect ; 75(3): 225-233, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28579304

RESUMEN

OBJECTIVES: Influenza is responsible for a large number of deaths which can only be estimated using modelling methods. Such methods have rarely been applied to describe the major socio-demographic characteristics of this disease burden. METHODS: We used quasi Poisson regression models with weekly counts of deaths and isolates of influenza A, B and respiratory syncytial virus for the period 1994 to 2008. RESULTS: The estimated average mortality rate was 13.5 per 100,000 people which was 1.8% of all deaths in New Zealand. Influenza mortality differed markedly by age, sex, ethnicity and socioeconomic position. Relatively vulnerable groups were males aged 65-79 years (Rate ratio (RR) = 1.9, 95% CI: 1.9, 1.9 compared with females), Maori (RR = 3.6, 95% CI: 3.6, 3.7 compared with European/Others aged 65-79 years), Pacific (RR = 2.4, 95% CI: 2.4, 2.4 compared with European/Others aged 65-79 years) and those living in the most deprived areas (RR = 1.8, 95% CI: 1.3, 2.4) for New Zealand Deprivation (NZDep) 9&10 (the most deprived) compared with NZDep 1&2 (the least deprived). CONCLUSIONS: These results support targeting influenza vaccination and other interventions to the most vulnerable groups, in particular Maori and Pacific people and men aged 65-79 years and those living in the most deprived areas.


Asunto(s)
Gripe Humana/mortalidad , Adolescente , Adulto , Factores de Edad , Anciano , Femenino , Humanos , Virus de la Influenza A/aislamiento & purificación , Virus de la Influenza B/aislamiento & purificación , Gripe Humana/etnología , Gripe Humana/virología , Masculino , Persona de Mediana Edad , Modelos Estadísticos , Nueva Zelanda/epidemiología , Análisis de Regresión , Factores de Riesgo , Estaciones del Año , Factores Sexuales , Factores Socioeconómicos , Población Blanca
19.
Vet Parasitol ; 216: 18-22, 2016 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-26801590

RESUMEN

Cryptosporidium is a protozoan that can cause gastro-intestinal illness with diarrhoea in a wide range of hosts. In fact some species of Cryptosporidium can infect the broad range of hosts. The current paper is focused to investigate monthly prevalence and diversity of Cryptosporidium spp. during the spring and early summer (March-June) in 2009 and 2010 in farms with no history of cryptosporidiosis. Animal samples were analyzed to elucidate the prevalence of Cryptosporidium in two regions, West and the East catchments in Ireland. Our investigation demonstrates the prevalence ranges from 14% to 26% an early summer peak (June) was observed. Based on the findings of this study Cryptosporidium ryanae (in cattle, horses), and Cryptosporidium bovis/xiaoi followed by Cryptosporidium parvum (in sheep) were found to be the predominant species in asymptomatic cases. The circulation of other Cryptosporidium species such as C. parvum, C. bovis, C. ubiquitum, C. andersoni and Cryptosporidium horse and pig genotypes in livestock was investigated.


Asunto(s)
Enfermedades de los Bovinos/epidemiología , Criptosporidiosis/epidemiología , Cryptosporidium/genética , Enfermedades de los Caballos/epidemiología , Enfermedades de las Ovejas/epidemiología , Animales , Bovinos , Enfermedades de los Bovinos/parasitología , Estudios Transversales , Criptosporidiosis/parasitología , ADN Protozoario/química , ADN Protozoario/aislamiento & purificación , Heces/parasitología , Técnica del Anticuerpo Fluorescente Directa/veterinaria , Variación Genética , Genotipo , Enfermedades de los Caballos/parasitología , Caballos , Irlanda/epidemiología , Reacción en Cadena de la Polimerasa/veterinaria , Prevalencia , Estaciones del Año , Ovinos , Enfermedades de las Ovejas/parasitología , Sialoglicoproteínas/química , Sialoglicoproteínas/genética
20.
Vaccine ; 33(33): 4087-92, 2015 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-26143611

RESUMEN

BACKGROUND: Influenza has a substantially but poorly measured impact on population health. Estimating its true contribution to hospitalisations remains a challenge. METHODS: We used simple and comprehensive negative binomial regression models with weekly counts of hospitalisations and isolates of influenza A, B and respiratory syncytial virus for the period 1994- 2008. RESULTS: The estimated annual national average number of hospitalisations attributable to influenza was 822.1(95% CI: 815.3, 828.9) for pneumonia and influenza, 1861.3 (95% CI: 1842.9, 1879.7) for respiratory illness, 12.1 (95% CI: 2.6, 21.6) for circulatory illness, 2260.0 (95% CI: 2212.2, 2307.8) for all medical illness and 2419.9 (95% CI: 2356.4, 2483.4) for all causes. The contribution of influenza to total hospitalisations was about nine times larger than indicated by routine discharge data. New Zealanders 80 years of age and older had the highest annual excess rates of influenza-related hospitalisations (327.8 per 100,000); followed by infants under 1 year (244.5 per 100,000). Estimated influenza hospitalisation rates were also markedly higher in Pacific (83.3 per 100,000) and Maori (80.0 per 100,000) compared with European/Others (58.1 per 100,000). Respiratory illness was the major contributor to all cause hospitalisations attributed to influenza accounting for 77%. Influenza hospitalisations included only a negligible contribution from circulatory illness. CONCLUSION: These findings support efforts to reduce the impact of influenza, particularly for the most vulnerable population groups highlighted here. Analysis of the cost-effectiveness of such interventions needs to consider these higher modelled estimates of disease impact.


Asunto(s)
Hospitalización , Gripe Humana , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Humanos , Incidencia , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Nueva Zelanda/epidemiología , Adulto Joven
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