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1.
Mar Pollut Bull ; 142: 335-349, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-31232312

RESUMEN

Anthropogenic contamination of beaches in the south of Brazil was assessed by detection of Escherichia coli, human mastadenovirus species C (HAdV-C) and F (HAdV-F) and hepatitis E virus (HEV). Sampling was carried out in October (2016), and in January, April and July (2017). Water, sediment, sea surface microlayer (SML), bivalves, and air sentinel samples were evaluated. Quantitative microbiological risk assessment (QMRA) was used to estimate the probability of swimmer infection. HAdV-C was present in 26% of the samples, for both qPCR and viral isolation. The highest rates of detection in genomic copies (GC) were in water (2.42E+10 GC/L), SML (2.08E+10 GC/L), sediment (3.82E+08 GC/g) and bivalves (3.91E+07 GC/g). QMRA estimated daily and annual risks with a maximum value (9.99E-01) in almost all of the samples. Viable HAdV-C was often detected in the SML, pointing that this is a source of infection for people bathing in these waters.


Asunto(s)
Adenovirus Humanos/aislamiento & purificación , Bivalvos/virología , Sedimentos Geológicos/virología , Agua de Mar/virología , Adenovirus Humanos/genética , Animales , Playas , Brasil , Monitoreo del Ambiente , Escherichia coli/genética , Escherichia coli/aislamiento & purificación , Virus de la Hepatitis E/genética , Virus de la Hepatitis E/aislamiento & purificación , Humanos , Reacción en Cadena en Tiempo Real de la Polimerasa , Medición de Riesgo/métodos , Natación , Microbiología del Agua
2.
Food Environ Virol ; 11(3): 288-296, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31154653

RESUMEN

This study was conducted to evaluate the microbiological quality of a mangrove estuary in the Vitória Bay region, Espírito Santo, Brazil. We analyzed the presence and concentration of enteric viruses and thermotolerant coliforms in water, mussels (Mytella charruana and Mytella guyanensis), and oysters (Crassostrea rhizophorae), collected over a 13-month period. Human adenovirus, rotavirus A (RVA), and norovirus genogroup II were analyzed by quantitative PCR. The highest viral load was found in RVA-positive samples with a concentration of 3.0 × 104 genome copies (GC) L-1 in water samples and 1.3 × 105 GC g-1 in bivalves. RVA was the most prevalent virus in all matrices. Thermotolerant coliforms were quantified as colony-forming units (CFU) by the membrane filtration method. The concentration of these bacteria in water was in accordance with the Brazilian standard for recreational waters (< 250 CFU 100 mL-1) during most of the monitoring period (12 out of 13 months). However, thermotolerant coliform concentrations of 3.0, 3.1, and 2.6 log CFU 100 g-1 were detected in M. charruana, M. guyanensis, and C. rhizophorae, respectively. The presence of human-specific viruses in water and bivalves reflects the strong anthropogenic impact on the mangrove and serves as an early warning of waterborne and foodborne disease outbreaks resulting from the consumption of shellfish and the practice of water recreational activities in the region.


Asunto(s)
Bivalvos/virología , Crassostrea/virología , Enterovirus/aislamiento & purificación , Agua de Mar/virología , Mariscos/virología , Animales , Brasil , Enterovirus/química , Enterovirus/clasificación , Enterovirus/genética , Infecciones por Enterovirus/virología , Estuarios , Contaminación de Alimentos/análisis , Calor , Humanos
3.
J Water Health ; 16(6): 970-979, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30540271

RESUMEN

The contamination of mussels and oysters by viruses and bacteria is often associated with water contamination and gastroenteritis in humans. The present study evaluated viral and bacterial contamination in 380 samples, from nine mollusk-producing regions in coastal water north of the Brazilian Amazon. Rotavirus contamination was studied for groups A to H, using a two-step SYBR Green RT-qPCR (quantitative reverse transcription polymerase chain reaction), and bacterial families Enterobacteriaceae, Vibrionaceae, and Aeromonadaceae by classical and molecular methods. From the 19 pools analyzed, 26.3% (5/19) were positive for group A Rotavirus, I2 genotype for VP6 region, without amplifications for groups B-H. Bacteriological analysis identified Escherichia coli isolates in 89.5% (17/19) with identification of atypical enteropathogenic E. coli aEPEC in 10.5% (2/19), Salmonella (Groups C1 and G) (10.5%, 2/19), Vibrio alginolyticus (57.9%, 11/19) V. parahaemolyticus (63.2%, 12/19), V. fluvialis (42.1%, 8/19), V. vulnificus (10.5%, 2/19), V. cholerae non-O1, non O139(10.5%, 2/19) and Aeromonas salmonicida (52.6%, 10/19). All the samples investigated presented some level of contamination by enterobacteria, rotavirus, or both, and these results may reflect the level of contamination in the Northern Amazon Region, due to the natural maintenance of some of these agents or by the proximity with human populations and their sewer.


Asunto(s)
Bivalvos/virología , Monitoreo del Ambiente , Rotavirus , Animales , Brasil , Escherichia coli , Reacción en Cadena en Tiempo Real de la Polimerasa , Microbiología del Agua
4.
Int J Food Microbiol ; 266: 363-371, 2018 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-29074195

RESUMEN

Bivalve mollusks are filter feeders and may accumulate human pathogens in their tissues. Many studies demonstrated human diseases associated with bivalve consumption, especially oysters. Anomalocardia brasiliana clams are distributed along the Brazilian coastal area and are an exotic ingredient for some typical dishes in Brazil. Even though there are several reports describing the contamination of oysters and mussels with human pathogens, there is a lack of studies reporting contamination of A. brasiliana with human pathogens. An evaluation of natural microbiological contamination in A. brasiliana samples over a period of 18months (November 2014 to April 2016) showed that the bacteria indices were in accordance with Brazilian regulations (E. coli<230MPN and Salmonella sp. absent in 25g of meat). However, the enteric viruses evaluated were detected throughout the analysis period, with the highest result for the hepatitis A virus (HAV); followed by Rotavirus-A (RVA); Human Adenovirus (HAdV) and Norovirus GI (NoV GI). The bioaccumulation of enteric viruses by A. brasiliana during a period of 24h was performed using NoV GI and GII, HAV, RVA and HAdV as models. Interestingly the mollusk demonstrated different uptake behaviors in relation to these viruses throughout the time period. NoV GI was the most adsorbed virus after 24h. HAV concentration was <1% at 3h, but it increased to <10% at 8h, remaining unchanged until 12h, and decreasing to <3% at 24h; HAdV reached its highest concentration at 12h, being released by the animals and lowering to <3% at 24h. RVA bioaccumulation was unstable over time, reaching its highest values after 24h (<5%); NoV GII bioaccumulation remained <1%. Thermal inactivation of HAdV-2 in A. brasiliana was also evaluated. After the usual gentle cooking procedure using different times (0, 1, 1.5, 3 and 5mins), viral infectivity was evaluated using ICC-et-RT-qPCR. The temperature inside the DT remained <80°C over time and after 5min of cooking the HAdV reached a decay of 90% (1 log10). The results showed a real warn to the consumers that can be exposed to infectious human viruses if they eat these clams improperly cooked. HAV was the most detected virus in these animals, which may lead to outbreaks. A. brasiliana exhibited distinct behavior in NoV GI bioaccumulation and persistence, pointing to the need for further studies about the cellular ligands used by these viruses to become attached to these clams.


Asunto(s)
Bivalvos/virología , Enterovirus/fisiología , Animales , Brasil , Enterovirus/aislamiento & purificación , Virus de la Hepatitis A/genética , Ligandos , Reacción en Cadena en Tiempo Real de la Polimerasa , Inactivación de Virus
5.
Sci Rep ; 6: 35237, 2016 10 14.
Artículo en Inglés | MEDLINE | ID: mdl-27739526

RESUMEN

Members of the family Marseilleviridae are giant viruses that have the ability to infect amoebas. Such viruses were initially described in 2009. Since then, this family has grown, and diverse members have been found in different environments and geographic locations. Previous phylogenetic analyses suggested the existence of four marseillevirus lineages. A fourth lineage was described with the discovery of the Brazilian marseillevirus (BrMr), isolated from Pampulha Lake, Brazil. Here we describe the isolation and characterization of the Golden marseillevirus (GMar), a new marseillevirus isolated from golden mussels (Limnoperna fortunei) in South of Brazil. This new representative of Marseilleviridae has circular, double-stranded (dsDNA) that contains 360, 610 base pairs and encodes 483 open read frames (ORFs). The complete virus genome was sequenced and phylogenic analyses indicated clear differences between this virus and other marseilleviruses. In addition, this is the only marseillevirus so far that has been isolated from mussels, and this report expands the diversity of environments from which giant viruses could be recovered.


Asunto(s)
Bivalvos/virología , Virus Gigantes/genética , Filogenia , Virión/genética , Animales , Brasil , Virus ADN/genética , ADN Viral/genética , Genoma Viral , Virus Gigantes/clasificación , Virus Gigantes/aislamiento & purificación , Lagos , Análisis de Secuencia de ADN , Virión/aislamiento & purificación
6.
Food Environ Virol ; 8(3): 215-20, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27221088

RESUMEN

Foodborne viruses are a common and, probably, the most under-recognized cause of outbreaks of gastroenteritis. Among the main foods involved in the transmission of human enteric viruses are mollusks, and fruits and vegetables irrigated with wastewater and/or washed with non-potable water or contaminated by contact with surfaces or hands of the infected personnel during its preparation. In this study, 134 food samples were analyzed for the detection of Norovirus, Rotavirus, and Hepatitis A virus (HAV) by amplification of conserved regions of these viruses. From the 134 analyzed samples, 14 were positive for HAV, 6 for Norovirus, and 11 for Rotavirus. This is the first report in Mexico where emphasis is given to the presence of HAV and Norovirus on perishable foods and food from fisheries, as well as Rotavirus on frozen vegetables, confirming the role of vegetables and bivalve mollusks as transmitting vehicles of enteric viruses.


Asunto(s)
Bivalvos/virología , Enterovirus/aislamiento & purificación , Contaminación de Alimentos/análisis , Frutas/virología , Mariscos/virología , Verduras/virología , Animales , Enterovirus/clasificación , Enterovirus/genética , Infecciones por Enterovirus/virología , Humanos , México
7.
Euro Surveill ; 21(3): 30113, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26836217

RESUMEN

This report describes an outbreak investigation starting with two closely related suspected food-borne clusters of Dutch hepatitis A cases, nine primary cases in total, with an unknown source in the Netherlands. The hepatitis A virus (HAV) genotype IA sequences of both clusters were highly similar (459/460 nt) and were not reported earlier. Food questionnaires and a case-control study revealed an association with consumption of mussels. Analysis of mussel supply chains identified the most likely production area. International enquiries led to identification of a cluster of patients near this production area with identical HAV sequences with onsets predating the first Dutch cluster of cases. The most likely source for this cluster was a case who returned from an endemic area in Central America, and a subsequent household cluster from which treated domestic sewage was discharged into the suspected mussel production area. Notably, mussels from this area were also consumed by a separate case in the United Kingdom sharing an identical strain with the second Dutch cluster. In conclusion, a small number of patients in a non-endemic area led to geographically dispersed hepatitis A outbreaks with food as vehicle. This link would have gone unnoticed without sequence analyses and international collaboration.


Asunto(s)
Bivalvos/virología , Brotes de Enfermedades/estadística & datos numéricos , Genoma Viral , Virus de la Hepatitis A/genética , Hepatitis A/epidemiología , Mariscos/virología , Adolescente , Adulto , Animales , Estudios de Casos y Controles , América Central , Embrión de Pollo , Niño , Análisis por Conglomerados , Femenino , Genotipo , Hepatitis A/diagnóstico , Hepatitis A/virología , Virus de la Hepatitis A/aislamiento & purificación , Humanos , Masculino , Datos de Secuencia Molecular , Países Bajos/epidemiología , Filogenia , ARN Viral/sangre , ARN Viral/genética , ARN Viral/aislamiento & purificación , Factores de Riesgo , Análisis de Secuencia de ADN , Viaje , Reino Unido/epidemiología
8.
Foodborne Pathog Dis ; 10(6): 528-32, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23614798

RESUMEN

Viruses are the leading cause of foodborne illness associated with the consumption of raw or slightly cooked contaminated shellfish. The aim of this study was to evaluate the prevalence of hepatitis A virus in molluscs. Standard and real-time reverse transcription-polymerase chain reaction procedures were used to monitor bivalve molluscs from the Granada fish markets (southern Spain) for this human enteric virus. Between February 2009 and October 2010, we collected a total of 329 samples of different types of bivalve molluscs (mussels, smooth clams, striped venus, and grooved clams). The results showed the presence of hepatitis A virus in 8.5% of the 329 samples analyzed. We can therefore confirm that conventional fecal indicators are unreliable for demonstrating the presence or absence of viruses. The presence of hepatitis A virus in molluscs destined for human consumption is a potential health risk in southern Spain.


Asunto(s)
Bivalvos/virología , Virus de la Hepatitis A Humana/crecimiento & desarrollo , Mariscos/virología , Animales , Escherichia coli/clasificación , Escherichia coli/crecimiento & desarrollo , Escherichia coli/aislamiento & purificación , Calidad de los Alimentos , Enfermedades Transmitidas por los Alimentos/virología , Virus de la Hepatitis A Humana/clasificación , Virus de la Hepatitis A Humana/aislamiento & purificación , Humanos , Mar Mediterráneo , Tipificación Molecular , Mytilus/virología , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Estaciones del Año , Mariscos/economía , España
9.
Appl Environ Microbiol ; 77(12): 4208-16, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21531842

RESUMEN

Bacteriophages are the most abundant and genetically diverse viruses on Earth, with complex ecology in both quantitative and qualitative terms. Somatic coliphages (SC) have been reported to be good indicators of fecal pollution in seawater. This study focused on determining the concentration of SC and their diversity by electron microscopy of seawater, plankton, and bivalve samples collected at three coastal regions in São Paulo, Brazil. The SC counts varied from <1 to 3.4 × 10(3) PFU/100 ml in seawater (73 samples tested), from <1 to 4.7 × 10(2) PFU/g in plankton (46 samples tested), and from <1 to 2.2 × 10(1) PFU/g in bivalves (11 samples tested). In seawater samples, a relationship between the thermotolerant coliforms and Escherichia coli and SC was observed at the three regions (P = 0.0001) according to the anthropogenic activities present at each region. However, SC were found in plankton samples from three regions: Baixada Santista (17/20), Canal de São Sebastião (6/14), and Ubatuba (3/12). In seawater samples collected from Baixada Santista, four morphotypes were observed: A1 (4.5%), B1 (50%), C1 (36.4%), and D1 (9.1%). One coliphage, Siphoviridae type T1, had the longest tail: between 939 and 995 nm. In plankton samples, Siphoviridae (65.8%), Podoviridae (15.8%), Microviridae (15.8%), and Myoviridae (2.6%) were found. In bivalves, only the morphotype B1 was observed. These SC were associated with enteric hosts: enterobacteria, E. coli, Proteus, Salmonella, and Yersinia. Baixada Santista is an area containing a high level of fecal pollution compared to those in the Canal de São Sebastião and Ubatuba. This is the first report of coliphage diversity in seawater, plankton, and bivalve samples collected from São Paulo coastal regions. A better characterization of SC diversity in coastal environments will help with the management and evaluation of the microbiological risks for recreation, seafood cultivation, and consumption.


Asunto(s)
Biodiversidad , Bivalvos/virología , Colifagos/clasificación , Colifagos/aislamiento & purificación , Plancton/virología , Agua de Mar/virología , Animales , Brasil , Colifagos/genética , Colifagos/ultraestructura , Carga Viral , Virión/ultraestructura
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