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1.
Pathogens ; 11(1)2021 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-35055965

RESUMEN

BACKGROUND: With the current climate change crisis and its influence on infectious disease transmission there is an increased desire to understand its impact on infectious diseases globally. Hantaviruses are found worldwide, causing infectious diseases such as haemorrhagic fever with renal syndrome (HFRS) and hantavirus cardiopulmonary syndrome (HCPS)/hantavirus pulmonary syndrome (HPS) in tropical regions such as Latin America and the Caribbean (LAC). These regions are inherently vulnerable to climate change impacts, infectious disease outbreaks and natural disasters. Hantaviruses are zoonotic viruses present in multiple rodent hosts resident in Neotropical ecosystems within LAC and are involved in hantavirus transmission. METHODS: We conducted a systematic review to assess the association of climatic factors with human hantavirus infections in the LAC region. Literature searches were conducted on MEDLINE and Web of Science databases for published studies according to Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) criteria. The inclusion criteria included at least eight human hantavirus cases, at least one climatic factor and study from > 1 LAC geographical location. RESULTS: In total, 383 papers were identified within the search criteria, but 13 studies met the inclusion criteria ranging from Brazil, Chile, Argentina, Bolivia and Panama in Latin America and a single study from Barbados in the Caribbean. Multiple mathematical models were utilized in the selected studies with varying power to generate robust risk and case estimates of human hantavirus infections linked to climatic factors. Strong evidence of hantavirus disease association with precipitation and habitat type factors were observed, but mixed evidence was observed for temperature and humidity. CONCLUSIONS: The interaction of climate and hantavirus diseases in LAC is likely complex due to the unknown identity of all vertebrate host reservoirs, circulation of multiple hantavirus strains, agricultural practices, climatic changes and challenged public health systems. There is an increasing need for more detailed systematic research on the influence of climate and other co-related social, abiotic, and biotic factors on infectious diseases in LAC to understand the complexity of vector-borne disease transmission in the Neotropics.

2.
Science ; 366(6471)2019 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-31831642

RESUMEN

The human impact on life on Earth has increased sharply since the 1970s, driven by the demands of a growing population with rising average per capita income. Nature is currently supplying more materials than ever before, but this has come at the high cost of unprecedented global declines in the extent and integrity of ecosystems, distinctness of local ecological communities, abundance and number of wild species, and the number of local domesticated varieties. Such changes reduce vital benefits that people receive from nature and threaten the quality of life of future generations. Both the benefits of an expanding economy and the costs of reducing nature's benefits are unequally distributed. The fabric of life on which we all depend-nature and its contributions to people-is unravelling rapidly. Despite the severity of the threats and lack of enough progress in tackling them to date, opportunities exist to change future trajectories through transformative action. Such action must begin immediately, however, and address the root economic, social, and technological causes of nature's deterioration.


Asunto(s)
Conservación de los Recursos Naturales , Actividades Humanas/tendencias , Calidad de Vida , Planeta Tierra , Humanos , Crecimiento Demográfico
3.
Parasit Vectors ; 7: 341, 2014 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-25052242

RESUMEN

BACKGROUND: Dengue is an acute arboviral disease responsible for most of the illness and death in tropical and subtropical regions. Over the last 25 years there has been increase epidemic activity of the disease in the Caribbean, with the co-circulation of multiple serotypes. An understanding of the space and time dynamics of dengue could provide health agencies with important clues for reducing its impact. METHODS: Dengue Haemorrhagic Fever (DHF) cases observed for the period 1998-2004 were georeferenced using Geographic Information System software. Spatial clustering was calculated for individual years and for the entire study period using the Nearest Neighbor Index. Space and time interaction between DHF cases was determined using the Knox Test while the Nearest Neighbor Hierarchical method was used to extract DHF hot spots. All space and time distances calculated were validated using the Pearson r significance test. RESULTS: Results shows that (1) a decrease in mean distance between DHF cases correlates with activity leading up to an outbreak, (2) a decrease in temporal distance between DHF cases leads to increased geographic spread of the disease, with an outbreak occurrence about every 2 years, and (3) a general pattern in the movement of dengue incidents from more rural to urban settings leading up to an outbreak with hotspot areas associated with transportation hubs in Trinidad. CONCLUSION: Considering only the spatial dimension of the disease, results suggest that DHF cases become more concentrated leading up to an outbreak. However, with the additional consideration of time, results suggest that when an outbreak occurs incidents occur more rapidly in time leading to a parallel increase in the rate of distribution of the disease across space. The results of this study can be used by public health officers to help visualize and understand the spatial and temporal patterns of dengue, and to prepare warnings for the public. Dengue space-time patterns and hotspot detection will provide useful information to support public health officers in their efforts to control and predict dengue spread over critical hotspots allowing better allocation of resources.


Asunto(s)
Dengue/epidemiología , Viaje , Análisis por Conglomerados , Dengue/transmisión , Humanos , Incidencia , Estudios Retrospectivos , Factores de Tiempo , Trinidad y Tobago/epidemiología
4.
Mar Pollut Bull ; 64(1): 169-173, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22114951

RESUMEN

Concentrations of heavy metals were determined in nearshore marine sediments and fish tissue from Sea Lots area on the west coast, at Caroni Lagoon National Park, and in the Point Lisas harbor, Trinidad. The most dominant metals found in sediments were Al, Fe and Zn with mean concentrations highest at Sea Lots (Al-39420 µg/g; Fe-45640 µg/g; Zn-245 µg/g), when compared to sediments from Point Lisas (Al-11936 µg/g; Fe-30171 µg/g; Zn-69 µg/g) and Caroni (Al-0400 µg/g; Fe-19000 µg/g; Zn-32 µg/g), High concentration of Cu, Al, Fe and Zn were also detected in fish tissue from Point Lisas and Caroni. Metal concentrations in fish tissue showed significant correlation with sediment metals concentration, which suggests that tissue levels are influenced by sediment concentration. Of the metals, only Zn, Hg and Cu had a bioaccumulation factor (BAF) greater than one, which suggests a high bioaccumulation potential for these metals.


Asunto(s)
Monitoreo del Ambiente , Peces/metabolismo , Sedimentos Geológicos/química , Metales/análisis , Contaminantes Químicos del Agua/análisis , Animales , Metales/metabolismo , Metales/normas , Agua de Mar/química , Trinidad y Tobago , Contaminantes Químicos del Agua/metabolismo , Contaminantes Químicos del Agua/normas , Contaminación Química del Agua/estadística & datos numéricos
5.
Mar Pollut Bull ; 62(6): 1324-32, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21529852

RESUMEN

Concentrations of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) were determined in nearshore marine surficial sediments from three locations in Trinidad. Sediments were sampled at Sea Lots on the west coast, in south Port-of-Spain Harbor, south of Sea Lots at Caroni Lagoon National Park, and on Trinidad's east coast at Manzanilla. Total PCB concentrations in Sea Lots sediments ranged from 62 to 601ng/g (dry weight {dw}), which was higher than at Caroni and Manzanilla, 13 and 8ng/g dw, respectively. Total OCP concentrations at Sea Lots were ranged from 44.5 to 145ng/g dw, compared with 13.1 and 23.8n/g (dw), for Caroni and Manzanilla respectively. The concentrations of PCBs and of some OCPs in sediments from Sea Lots were above the Canadian interim sediment quality guidelines. To date, this data is the first report on the levels of PCBs and other organochlorine compounds from Trinidad and Tobago.


Asunto(s)
Sedimentos Geológicos/química , Hidrocarburos Clorados/análisis , Plaguicidas/análisis , Bifenilos Policlorados/análisis , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente , Trinidad y Tobago , Contaminación Química del Agua/estadística & datos numéricos
6.
Mar. pollut. bull ; Mar. pollut. bull;58(6): 928-934, Jun. 2009. tabmapas graf
Artículo en Inglés | MedCarib | ID: med-17802

RESUMEN

Organochlorine compounds are a class of pollutants considered toxic to humans, fish and wildlife, and show great potential for accumulation and persistence in the environment. In May 1995, the United Nations Environmental Program (UNEP) Governing Council adopted Decision 18/32 (GC18/32) on persistent organic pollutants (POPs), the goal of which was to initiate an expeditious assessment process, initially beginning with twelve priority POPs: polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs or dioxins), polychlorinated dibenzofurans (PCDFs), aldrin, dieldrin, DDT, endrin, chlordane, hexachlorobenzene (HCB), mirex, toxaphene and heptachlor. In 1997, based on recommendations from the Intergovernmental Forum on Chemical Safety (IFCS), UNEP decided that immediate international action should be initiated to protect human health and the environment by reducing and/or eliminating emissions and discharges of the twelve persistent organic pollutants (the ‘dirty dozen’) specified by GC18/32. UNEP decision GC19/13C proposed a series of immediate action responses based on the IFCS recommendations: (1) general awareness of POPs; (2) information exchange between countries and organizations; and (3) improved availability of information and expertise on alternatives to POPs (UNEP, 2001 UNEP. 2001. The Stockholm Convention on Persistent Organic Pollutants. . English. PDF (accessed 29.09.08.).UNEP, 2001). In accordance with the mandates of UNEP GC18/32, GC19/13C and GC20/24, the first global legally binding instrument on POPs, ‘The Stockholm Convention’, was agreed upon. Trinidad and Tobago declared its accession to this in December 2002 and the Convention became legally binding in 2004 after France became the fiftieth country to ratify the agreement...


Asunto(s)
Animales , Humanos , Insecticidas Organoclorados , Contaminantes del Agua/toxicidad , Contaminantes Químicos del Agua/toxicidad , Contaminantes Ambientales/toxicidad , Trinidad y Tobago
8.
Environ Monit Assess ; 127(1-3): 307-13, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16897500

RESUMEN

The acute salinity tolerance of three tropical freshwater cladoceran species, M. macleayi, C. rigaudii and D. brachyurum was determined. The existence of these species represented new records for Trinidad and Tobago, a tropical Caribbean island. It has a large oil based industry, in which, the primary effluent (saline produced water) is discharged directly into many freshwater systems. Cladoceran species are used routinely in temperate regions, to assess the impacts of chemicals and effluents in freshwater systems. However, relatively few studies have assessed the salinity tolerance of these organisms. Test organisms were assayed using seven salinity treatments (0, 1, 3, 5, 10, 15, 20, 25 per thousand) prepared by volumetrically mixing natural filtered seawater with dilution water. C. rigaudii had a 48 h LC50 of 1.6 per thousand, M. macleayi 1.5 per thousand and D. brachyurum <1 per thousand. The CSmax (critical salinity maximum) for C. rigaudii and M. macleayi was 3 per thousand after 48 h, compared to 1 per thousand for D. brachyurum. There was no salinity value at which there was 100% survival. The resulting salinity response curve was a straight line which indicated that each species was intolerant of salt. Consequently, any of these can be considered as a representative freshwater organism for toxicity testing in Trinidad and Tobago.


Asunto(s)
Cladóceros , Agua Dulce/análisis , Ríos , Cloruro de Sodio/análisis , Animales , Brasil , Ríos/química , Especificidad de la Especie
9.
Mar Pollut Bull ; 48(7-8): 784-9, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15041435

RESUMEN

Corbula caribea is the most common non-polychaete macrofaunal organism identified at a large natural oil seep at La Brea in south Trinidad. It is hypothesized that these animals may possess (NADPH-ferrihemoprotein reductase) a component of the Mixed Function Oxygenase system (MFO), which may allow them to ameliorate the potentially deleterious effects resulting from exposure to the high levels of petroleum hydrocarbons within this environment. This study was designed to determine whether organisms from the seep site showed greater enzyme activity when compared to organisms from a non-seep reference site. NADPH-ferrihemoprotein reductase activity was determined by incubating 10 microm cryostat sections with nitro-blue tetrazolium. The reaction product was determined by visual assessment and quantified by measuring the relative mean stain intensity. The intense staining, indicative of enzyme activity was evident in the digestive epithelia of seep animals. Observations indicated that organisms from the seep showed more intense staining, indicating greater enzyme activity, when compared to animals from a non-seep reference site. The relative stain intensity of NADPH-ferrihemoprotein reductase determined for organisms from the seep was 61.30. This was significantly higher than the stain intensity determined for organisms from the non-seep reference site (7.11). This supported visual assessments, which suggested that the seep organisms showed higher enzyme activity than organisms from the non-seep site. The results suggest that NADPH-ferrihemoprotein reductase may be present in Corbula caribea from the seep site and not in those from the non-seep site. It is possible that this enzyme may contribute to these animals ability to tolerate chronic exposure to petroleum hydrocarbons and offer then a selective advantage for survival the seep environment.


Asunto(s)
Adaptación Fisiológica , Bivalvos/enzimología , NADPH-Ferrihemoproteína Reductasa/análisis , Petróleo/metabolismo , Animales , Histocitoquímica , Nitroazul de Tetrazolio
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