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1.
Rev Sci Tech ; 38(2): 437-457, 2019 Sep.
Artigo em Inglês, Francês, Espanhol | MEDLINE | ID: mdl-31866683

RESUMO

The growth of aquaculture over the past 50 years has been accompanied by the emergence of aquatic animal diseases, many of which have spread to become pandemic in countries or continents. An analysis of 400 emerging disease events in aquatic animals that were logged by the Centre for Environment, Fisheries and Aquaculture Science between 2002 and 2017 revealed that more than half were caused by viruses. However, in molluscs, most events were parasitic. Categorising these events indicated that the key processes underpinning emergence were the movement of live animals and host switching. Profiles of key pathogens further illustrate the importance of wild aquatic animals as the source of new infections in farmed animals. It is also clear that the spread of new diseases through the largescale movement of aquatic animals for farming, for food and for the ornamental trade has allowed many to achieve pandemic status. Many viral pathogens of fish (e.g. infectious salmon anaemia, viral haemorrhagic septicaemia) and shrimp (e.g. white spot syndrome virus) affect a large proportion of the global production of key susceptible species. Wild aquatic animal populations have also been severely affected by pandemic diseases, best exemplified by Batrachochytrium dendrobatidis, a fungal infection of amphibians, whose emergence and spread were driven by the movement of animals for the ornamental trade. Batrachochytrium dendrobatidis is now widespread in the tropics and subtropics and has caused local extinctions of susceptible amphibian hosts. Given the rising demand for seafood, aquacultural production will continue to grow and diseases will continue to emerge. Some will inevitably achieve pandemic status, having significant impacts on production and trade, unless there are considerable changes in global monitoring and the response to aquatic animal diseases.


Assuntos
Anfíbios/microbiologia , Doenças dos Peixes/epidemiologia , Pandemias/veterinária , Frutos do Mar , Animais , Aquicultura , Quitridiomicetos , Micoses/microbiologia , Micoses/veterinária , Frutos do Mar/microbiologia , Frutos do Mar/parasitologia , Frutos do Mar/virologia
2.
Arch Virol ; 164(12): 3035-3043, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31602543

RESUMO

Seasonally recurrent outbreaks of mass mortality in Pacific oysters (Crassostrea gigas) caused by microvariant genotypes of ostreid herpesvirus 1 (OsHV-1) occur in Europe, New Zealand and Australia. The incubation period for OsHV-1 under experimental conditions is 48-72 hours and depends on water temperature, as does the mortality. An in vivo growth curve for OsHV-1 was determined by quantifying OsHV-1 DNA at 10 time points between 2 and 72 hours after exposure to OsHV-1. The peak replication rate was the same at 18 °C and 22 °C; however, there was a longer period of amplification leading to a higher peak concentration at 22 °C (2.34 × 107 copies/mg at 18 hours) compared to 18 °C (1.38 × 105 copies/mg at 12 hours). The peak viral concentration preceded mortality by 72 hours and 20 hours at 18 °C and 22 °C, respectively. Cumulative mortality to day 14 was 45.9% at 22 °C compared to 0.3% at 18 °C. The prevalence of OsHV-1 infection after 14 days at 18 °C was 33.3%. No mortality from OsHV-1 occurred when the water temperature in tanks of oysters challenged at 18 °C was increased to 22 °C for 14 days. The influence of water temperature prior to exposure to OsHV-1 and during the initial virus replication is an important determinant of the outcome of infection in C. gigas.


Assuntos
Crassostrea/fisiologia , Crassostrea/virologia , Vírus de DNA/crescimento & desenvolvimento , Frutos do Mar/virologia , Animais , Crassostrea/crescimento & desenvolvimento , Vírus de DNA/genética , DNA Viral/genética , Temperatura
3.
Mar Pollut Bull ; 149: 110524, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31543476

RESUMO

More stable than bacteria in environmental samples, enteric viruses are generally related to outbreaks of gastroenteritis caused by the consumption of contaminated oysters. This study evaluated: i) the dynamic processes of enteric viral models bioaccumulation by Crassostrea gigas oysters artificially contaminated; ii) the stability of these viruses in oysters in controlled temperature conditions and iii) the effect of UV light in inactivating these viruses in depurated oysters. Plaque assay (PA) was used to assess the infectivity of both viral models. Cell culture coupled with RT-qPCR (ICC-RT-qPCR) was used to measure infectious adenovirus type 2 (HAdV-2) genomes and qPCR to measure genome copies of murine norovirus (MNV-1). The virus uptake through bioaccumulation behave differently: HAdV-2 reached its peak of uptake faster than MNV-1. Both viruses showed high stability in oysters when maintained under 4 °C, but were completely inactivated in steamed oysters. The HAdV-2 was completely inactivated after 12 h of depuration with UV light and after 24 h without UV light. After 72 h of depuration, MNV-1 was still detected in both tanks, probably due to the stronger interaction of this virus with the oyster's tissues. This study demonstrated the importance of a secure depuration time in ensuring a clean and safe product, and that the steaming process is the safest way to prepare oysters for consumption.


Assuntos
Adenovírus Humanos/isolamento & purificação , Crassostrea/virologia , Norovirus/isolamento & purificação , Frutos do Mar/virologia , Células A549 , Adenovírus Humanos/genética , Animais , Culinária , Microbiologia de Alimentos , Armazenamento de Alimentos , Humanos , Camundongos , Norovirus/genética , Norovirus/patogenicidade , Células RAW 264.7 , Reação em Cadeia da Polimerase em Tempo Real , Vapor , Temperatura , Raios Ultravioleta
4.
Artigo em Inglês | MEDLINE | ID: mdl-31331104

RESUMO

To assess the quality of shellfish harvest areas, bivalve mollusk samples from three coastal areas of the Campania region in Southwest Italy were evaluated for viruses over a three-year period (2015-2017). Screening of 289 samples from shellfish farms and other locations by qPCR and RT-qPCR identified hepatitis A virus (HAV; 8.9%), norovirus GI (NoVGI; 10.8%) and GII (NoVGII; 39.7%), rotavirus (RV; 9.0%), astrovirus (AsV; 20.8%), sapovirus (SaV; 18.8%), aichivirus-1 (AiV-1; 5.6%), and adenovirus (AdV, 5.6%). Hepatitis E virus (HEV) was never detected. Sequence analysis identified HAV as genotype IA and AdV as type 41. This study demonstrates the presence of different enteric viruses within bivalve mollusks, highlighting the limitations of the current EU classification system for shellfish growing waters.


Assuntos
Bivalves/virologia , Frutos do Mar/virologia , Vírus/isolamento & purificação , Animais , Monitoramento Ambiental , Contaminação de Alimentos/análise , Itália , Reação em Cadeia da Polimerase em Tempo Real , Vírus/genética
5.
J Food Sci ; 84(8): 2256-2260, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31334844

RESUMO

Human adenoviruses (HAdVs) are the foodborne enteric pathogens transmitted by the consumption of contaminated shellfish. In this study, the occurrence of enteric adenoviruses in finfish and shellfish was investigated by virus concentration and polymerase chain reaction (PCR). Total plate count, total coliform, and fecal coliform levels were determined and correlated with the presence of adenovirus. Samples of fish, bivalve mollusks, crustaceans, and cephalopods were collected from supermarkets, landing centers, and retail fish markets of Mumbai, India for the study. Overall, the adenovirus DNA was detected in 21.27% of all the samples analyzed. The highest incidence was detected in clams (14.89%), followed by oysters, shrimps, and finfish (2.13% each). High prevalence of enteric adenovirus in filter-feeding bivalves, such as clams and oysters, as well as in fish suggests persistent fecal contamination of coastal waters in the region of study. The occurrence of adenoviruses in samples showed a positive correlation with the bacteriological indicators of fecal contamination, suggesting that fecal indicator bacteria may be used to monitor the presence of adenoviruses in seafood. PRACTICAL APPLICATION: This research demonstrates the occurrence of human adenoviruse (HAdV) in fresh seafood and the utility of fecal coliforms as indicators of HAdV presence in seafood. The study emphasizes the need to identify HAdV in seafood as a human health hazard and implement measures to prevent sewage pollution of fish and shellfish harvesting areas in India.


Assuntos
Adenovírus Humanos/isolamento & purificação , Frutos do Mar/virologia , Adenovírus Humanos/classificação , Adenovírus Humanos/genética , Animais , Bivalves/virologia , Peixes/virologia , Contaminação de Alimentos/análise , Humanos , Índia , Ostreidae/virologia , Esgotos/virologia , Frutos do Mar/economia
6.
Food Environ Virol ; 11(4): 374-382, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31342414

RESUMO

Detection of noroviruses in bivalve shellfish is difficult because of the low concentration of norovirus and the presence of reverse transcription (RT)-PCR inhibitors. This study aimed to assess the presence of noroviruses in oysters extracted using a proteinase K extraction (ISO 15216 method) and an adsorption-elution method. Seventy oyster samples were extracted using the two extraction methods and evaluated using RT-nested PCR. The results showed norovirus detection rates at an equal frequency of 28.6%, of which a total of 48 (68.6%) samples had corresponding positive or negative results, while there were 22 (31.4%) samples with discrepant results. Norovirus genogroup (G)I, GII, and mixed GI and GII were detected in 20%, 4.3%, and 4.3% of samples, respectively, by the proteinase K extraction method, which comprised of GI.2, GI.5b, GI.6b, GII.4, and GII.17 genotypes. With the adsorption-elution method noroviruses were detected in 17.1%, 8.6%, and 2.9% of samples, respectively, which comprised of GI.2, GII.2, GII.4, and GII.17 genotypes. All norovirus-positive oyster samples were further estimated for genome copy number using RT-quantitative PCR. The oyster samples processed using the adsorption-elution method contained norovirus GI of 3.36 × 101-1.06 × 105 RNA copies/g of digestive tissues and GII of 1.29 × 103-1.62 × 104 RNA copies/g. Only GII (2.20 × 101 and 7.83 × 101 RNA copies/g) could be quantified in samples prepared using the proteinase K extraction method. The results demonstrate the different performance of the two sample-processing methods, and suggest the use of either extraction method in combination with RT-nested PCR for molecular surveillance of norovirus genotypes in oysters.


Assuntos
Norovirus/isolamento & purificação , Ostreidae/virologia , RNA Viral/isolamento & purificação , Frutos do Mar/virologia , Virologia/métodos , Animais , Genótipo , Norovirus/classificação , Norovirus/genética , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real
7.
Food Environ Virol ; 11(3): 288-296, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31154653

RESUMO

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.


Assuntos
Bivalves/virologia , Crassostrea/virologia , Enterovirus/isolamento & purificação , Água do Mar/virologia , Frutos do Mar/virologia , Animais , Brasil , Enterovirus/química , Enterovirus/classificação , Enterovirus/genética , Infecções por Enterovirus/virologia , Estuários , Contaminação de Alimentos/análise , Temperatura Alta , Humanos
8.
Food Environ Virol ; 11(3): 247-258, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31115869

RESUMO

Contamination of bivalve shellfish, particularly oysters, with norovirus is recognised as a significant food safety risk. Methods for quantification of norovirus in oysters using the quantitative real-time reverse transcription polymerase chain reaction (RT-qPCR) are well established, and various studies using RT-qPCR have detected norovirus in a considerable proportion of oyster samples, both in the UK and elsewhere. However, RT-qPCR detects viral genome, and by its nature is unable to discriminate between positive results caused by infectious viruses and those caused by non-infectious remnants including damaged virus particles and naked RNA. As a result, a number of alternative or complementary approaches to RT-qPCR testing have been proposed, including the use of infectious viral indicator organisms, most frequently F-specific RNA bacteriophage (F-RNA phage). In this study, we investigated the relationships between F-RNA phage and norovirus in digestive tissues from two sets of oyster samples, one randomly collected at retail (630 samples), and one linked to suspected norovirus illness outbreaks (nine samples). A positive association and correlation between PCR-detectable levels of genogroup II F-RNA bacteriophage (associated with human faecal contamination) and norovirus was found in both sets of samples, with more samples positive for genogroup II phage, at generally higher levels than norovirus. Levels of both viruses were higher in outbreak-related than retail samples. Infectious F-RNA phage was detected in 47.8% of all retail samples, and for a subset of 224 samples where characterisation of phage was carried out, infectious GII phage was detected in 30.4%. Infectious GII phage was detected in all outbreak-related samples. Determination of infectivity ratios by comparing levels of PCR-detectable (copies/g) and infectious GII phage (pfu/g) revealed that in the majority of cases less than 10% of virus detected by RT-qPCR was infectious. Application of these ratios to estimate infectious norovirus levels indicated that while 77.8% of outbreak-related samples contained > 5 estimated infectious norovirus/g, only 13.7% of retail samples did. Use of a combination of levels of PCR-detectable norovirus and infectious F-RNA phage showed that while only 7.0% of retail samples contained both > 100 copies/g norovirus and > 10 pfu/g F-RNA phage, these combined levels were present in 77.8% of outbreak-related samples, and 75.9% of retail samples with > 5 estimated infectious norovirus/g. We therefore suggest that combining RT-qPCR testing with a test for infectious F-RNA phage has the potential to better estimate health risks, and to better predict the presence of infectious norovirus than RT-qPCR testing alone.


Assuntos
Norovirus/crescimento & desenvolvimento , Ostreidae/virologia , Fagos RNA/crescimento & desenvolvimento , Frutos do Mar/virologia , Animais , Infecções por Caliciviridae/virologia , Fezes/virologia , Contaminação de Alimentos/análise , Gastroenterite/virologia , Genoma Viral , Humanos , Norovirus/genética , Fagos RNA/genética
9.
Int J Food Microbiol ; 299: 58-63, 2019 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-30954876

RESUMO

Bivalve molluscan shellfish, such as oysters, clams, and cockles, are well-recognized as vectors that concentrate foodborne pathogens by filter feeding. The objective of this study was to investigate the distribution and persistence of hepatitis A virus (HAV) in experimentally contaminated oysters that were either fed or not fed with algae. Oysters were experimentally contaminated with HAV and maintained in depuration conditions. qRT-PCR, immunohistochemistry (IHC), and in situ hybridization (ISH) were performed on oyster samples collected at 0, 1, 3, 5, and 7 days post-inoculation. When HAV-contaminated oysters were depurated for 7 days, HAV was detected in 91.1-97.8% of the digestive glands and gills. While the high viral load in the digestive glands in oysters did not change significantly regardless of algae-feeding, the viral load of the gills gradually decreased in both groups during the depuration. HAV antigen and RNA were detected in the digestive diverticula and connective tissues by both IHC and ISH. HAV was detected in the stomach, intestine, and gills by only ISH. The distribution of HAV in various oyster tissues may explain the persistence of contamination in oysters during the depuration process.


Assuntos
Microbiologia de Alimentos , Vírus da Hepatite A/fisiologia , Ostreidae/virologia , Animais , Manipulação de Alimentos , Trato Gastrointestinal/virologia , Brânquias/virologia , Vírus da Hepatite A/genética , Frutos do Mar/virologia , Fatores de Tempo
10.
Food Environ Virol ; 11(3): 268-273, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30982112

RESUMO

Norovirus (NoV) is the leading cause of acute viral gastroenteritis outbreaks in the world. These outbreaks are frequently associated with bivalve shellfish consumption, particularly because these products are often eaten raw or only slightly cooked. In Morocco, regulations concerning the acceptable levels of enteric bacteria indicator organisms in these products have been put in place. However, these regulations do not take into account the risk of viral contamination, and many gastroenteritis outbreaks have been linked to the ingestion of bivalve shellfish from areas that comply with the current food safety criteria. The aim of this study was to investigate NoV presence in shellfish samples (n = 104) collected at four sites owcff Oualidia lagoon (Moroccan Atlantic coast) from November 2015 to February 2017. Samples were analysed using real-time RT-PCR in accordance with the ISO 15216-2 method. NoVs of the genogroup II were detected in 7% of samples that were all collected during the winter months. Moreover, 71% of NoV-positive samples were harvested at sites upstream of the lagoon. These results highlight the need of regularly monitoring viral contamination in bivalve shellfish to limit the risk of viral gastroenteritis outbreaks.


Assuntos
Bivalves/virologia , Norovirus/isolamento & purificação , Água do Mar/virologia , Frutos do Mar/virologia , Animais , Bivalves/crescimento & desenvolvimento , Contaminação de Alimentos/análise , Gastroenterite/virologia , Humanos , Marrocos , Norovirus/classificação , Norovirus/genética , Reação em Cadeia da Polimerase em Tempo Real , Estações do Ano
11.
Food Environ Virol ; 11(3): 205-213, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30903597

RESUMO

This study investigated the synergistic effects of combined chlorine (200, 500, 700, and 1000 ppm) and vitamin B1 (1000, 2000, and 3000 ppm) on the murine norovirus-1 (MNV-1), a human norovirus (NoV) surrogate, on oyster surface. Vitamin B1 slightly reduced MNV-1 (0.04-0.3 log-reduction), whereas chlorine significantly reduced MNV-1 (0.4-1.0 log-reduction). The combined chlorine and vitamin B1 resulted in a 0.52-1.97 log-reduction of MNV-1. The synergistic reduction in the MNV titer was not dependent on the concentrations of chlorine and vitamin B1, and it ranged between 0.08 and 1.03 log10 PFU/mL. The largest synergistic reduction observed was for the combined 700 ppm chlorine and 1000 ppm vitamin B1. The pH and mechanical texture of the oysters were not significantly changed by the combined 0-1000 ppm chlorine and 3000 ppm vitamin B1. The overall sensory acceptability were significantly (P < 0.05) reduced in oysters treated with 1000 ppm chlorine and 3000 ppm vitamin B1 than in those treated with 0-700 ppm chlorine and 3000 ppm vitamin B1. This study suggests that the combined 700 ppm chlorine and 3000 ppm vitamin B1 could potentially be used to reduce NoV on oyster surface without causing concomitant changes in the mechanical texture, pH, or sensory qualities of the oysters.


Assuntos
Cloro/farmacologia , Crassostrea/virologia , Desinfetantes/farmacologia , Contaminação de Alimentos/prevenção & controle , Conservação de Alimentos/métodos , Norovirus/efeitos dos fármacos , Frutos do Mar/virologia , Tiamina/farmacologia , Animais , Sinergismo Farmacológico , Humanos , Norovirus/genética , Norovirus/crescimento & desenvolvimento , Paladar
12.
Food Environ Virol ; 11(2): 120-125, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30919239

RESUMO

Male-specific coliphages (MSCs) are currently used to assess the virologic quality of shellfish-growing waters and to assess the impact of sewage release or adverse weather events on bivalve shellfish. Since MSC can have either DNA or RNA genomes, and most research has been performed exclusively on RNA MSCs, persistence of M13, a DNA MSC, was evaluated for its persistence as a function of time and temperature within Eastern oysters (Crassostrea virginica). Oysters were individually exposed to seawater containing a total of 1010 to 1012 pfu of M13 for 24 h at 15 °C followed by maintenance in tanks with as many as 21 oysters in continuously UV-sterilized water for up to 6 weeks at either 7, 15, or 22 °C. Two trials for each temperature were performed combining three shucked oysters per time point which were assayed by tenfold serial dilution in triplicate. Initial contamination levels averaged 106.9 and ranged from 106.0 to 107.0 of M13. For oysters held for 3 weeks, log10 reductions were 1.7, 3.8, and 4.2 log10 at 7, 15, and 22 °C, respectively. Oysters held at 7 and 15 °C for 6 weeks showed average reductions of 3.6 and 5.1 log10, respectively, but still retained infectious M13. In total, this work shows that DNA MSC may decline within shellfish in a manner analogous to RNA MSCs.


Assuntos
Colífagos/isolamento & purificação , Crassostrea/virologia , DNA Viral/genética , Frutos do Mar/virologia , Animais , Colífagos/classificação , Colífagos/genética , Masculino , Água do Mar/virologia , Esgotos/virologia , Especificidade da Espécie , Temperatura , Poluição da Água
13.
Food Environ Virol ; 11(2): 138-148, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30900141

RESUMO

Two outbreaks of norovirus and acute gastroenteritis took place in Canada between November 2016 and April 2017. Both outbreaks were linked to oysters from British Columbia (BC) coastal waters. This paper describes the multi-agency investigations to identify the source and control the outbreak. Public health officials conducted interviews to determine case exposures. Traceback was conducted by collecting oyster tags from restaurants and analyzing them to determine the most common farms. Oyster samples were collected from case homes, restaurants, and harvest sites and tested for the presence of norovirus. Potential environmental pollution sources were investigated to identify the source of the outbreak. Four hundred and 49 cases were identified as part of the two outbreak waves. The oysters were traced to various geographically dispersed farms in BC coastal waters. Twelve farms were closed as a result of the investigations. No environmental pollution sources could be identified as the cause of the outbreak. Similarities in the timeframe, genotype, and geographic distribution of identified oyster farms indicate that they may have been one continuous event. Genotype data indicate that human sewage contamination was the likely cause of the outbreak, although no pollution source was identified.


Assuntos
Infecções por Caliciviridae/virologia , Gastroenterite/virologia , Norovirus/isolamento & purificação , Ostreidae/virologia , Frutos do Mar/virologia , Animais , Colúmbia Britânica/epidemiologia , Infecções por Caliciviridae/epidemiologia , Contaminação de Alimentos/análise , Gastroenterite/epidemiologia , Genótipo , Humanos , Norovirus/classificação , Norovirus/genética , Saúde Pública , Restaurantes/estatística & dados numéricos , Esgotos/virologia
14.
Viruses ; 11(3)2019 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-30841581

RESUMO

Human norovirus is the major cause of non-bacterial epidemic gastroenteritis. Human norovirus binds to environmental solids via specific and non-specific interactions, and several specific receptors for human norovirus have been reported. Among them, histo-blood group antigens (HBGA) are the most studied specific receptor. Studies have identified the presence of HBGA-like substances in the extracellular polymeric substances (EPS) and lipopolysaccharides (LPS) of human enteric bacteria present in aquatic environments, gastrointestinal cells, gills, and palps of shellfish, and cell walls, leaves, and veins of lettuce. These HBGA-like substances also interact with human norovirus in a genotype-dependent manner. Specific interactions between human norovirus and environmental matrices can affect norovirus removal, infectivity, inactivation, persistence, and circulation. This review summarizes the current knowledge and future directions related to the specific interactions between human norovirus and HBGA-like substances in environmental matrices and their possible effects on the fate and circulation of human norovirus.


Assuntos
Antígenos de Grupos Sanguíneos/metabolismo , Meio Ambiente , Norovirus/fisiologia , Sítios de Ligação , Vírus de DNA , Matriz Extracelular de Substâncias Poliméricas , Genótipo , Humanos , Alface/virologia , Lipopolissacarídeos , Norovirus/genética , Frutos do Mar/virologia , Águas Residuárias/virologia
15.
Int J Infect Dis ; 80: 66-72, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30639406

RESUMO

OBJECTIVES: Enteric viruses are responsible for foodborne and waterborne infections affecting a large number of people. Data on food and water viral contamination in the south of Italy (Sicily) are scarce and fragmentary. The aim of this study was to evaluate the presence of viral contamination in food, water samples, and surface swabs collected in Sicily METHODS: The survey was conducted on 108 shellfish, 23 water samples (seawater, pipe water, and torrent water), 52 vegetables, one peach and 17 berries, 11 gastronomic preparations containing fish products and/or raw vegetables, and 28 surface swabs. Hepatitis A virus (HAV), genogroup GI, GII, and GIV norovirus (NoV), enterovirus (EV), rotavirus (RoV), hepatitis E virus (HEV), adenovirus (AdV), and bocavirus (BoV) were detected by nested (RT) PCR, real-time PCR, and sequence analysis. RESULTS: The most frequently detected viruses in shellfish were HAV (13%), NoV (18.5%), and EV (7.4%). Bocavirus was found in 3.7%, HEV in 0.9%, and AdV in 1.9% of the molluscs. Of the 23 water samples, 21.7% were positive for GII NoV and 4.3% for RoV and HEV genotype 3. Of the 70 vegetable samples, 2.9% were positive for NoV GI (GI.5 and GI.6), 2.9% for EV, and 1.4% for HEV. In the gastronomic preparations, only one EV (9%) was detected. No enteric viruses were detected in the berries, fruit, or swabs analyzed. CONCLUSIONS: Molecular surveillance of water and food samples clearly demonstrated that human pathogenic viruses are widely found in aquatic environments and on vegetables, and confirmed the role of vegetables and bivalve molluscs as the main reservoirs.


Assuntos
Enterovirus/isolamento & purificação , Contaminação de Alimentos/análise , Microbiologia de Alimentos , Microbiologia da Água , Animais , DNA Viral/isolamento & purificação , Água Potável/virologia , Frutas/virologia , Vírus da Hepatite A/isolamento & purificação , Vírus da Hepatite E/isolamento & purificação , Humanos , Norovirus/isolamento & purificação , Rotavirus/isolamento & purificação , Alimentos Marinhos/virologia , Frutos do Mar/virologia , Sicília , Verduras/virologia , Poluição da Água
16.
J Fish Dis ; 42(4): 519-531, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30694526

RESUMO

We determined the complete genomic RNA sequence of a new type of betanodavirus Korea shellfish nervous necrosis virus (KSNNV) isolated from shellfish. Compared with other isolates representing four genotypes of betanodaviruses, the identity of the whole nucleotide sequence of the virus was in the range of 76%-83% with the presence of specific genetic motifs and formed a separate new branch in the phylogenetic analysis. In pathogenic analysis by immersion method, KSNNV-KOR1 shows 100% cumulative mortality like SFRG10/2012BGGa1 (RGNNV) in newly hatched sevenband grouper and mandarin fish, which is clearly different from those found in negative control groups. There were no significant differences in increasing rates of mortality and viral intra-tissue concentration of larval fishes infected with KSNNV-KOR1 at both 20 and 25°C water temperature. Histopathological examination of each fish species in the moribund stage revealed the presence of clear vacuoles in both brain and retinal tissues similar to typical histopathology features of RGNNV. In the present study, we first report a new betanodavirus from shellfish as the aetiological agent of viral nervous necrosis disease in fish with complete genomic nucleotide sequence and pathogenic analysis.


Assuntos
Doenças dos Peixes/virologia , Nodaviridae/genética , Nodaviridae/patogenicidade , Filogenia , Infecções por Vírus de RNA/veterinária , Frutos do Mar/virologia , Animais , Peixes/virologia , Genoma Viral , Genótipo , Nodaviridae/isolamento & purificação , RNA Viral/genética , República da Coreia , Alimentos Marinhos/virologia
17.
Int J Food Microbiol ; 288: 82-90, 2019 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-29229293

RESUMO

Hepatitis A virus (HAV) and norovirus are important agents of food-borne human viral illness, with common vehicles including bivalve molluscan shellfish, soft fruit and various vegetables. Outbreaks of viral illness due to contamination of the surfaces of foods, or food preparation surfaces by for example infected food handlers are also common. Virus analysis of food matrices can contribute towards risk management for these hazards and a two-part technical specification for determination of Hepatitis A virus and norovirus in food matrices (ISO/TS 15216:2013) was published jointly by the European Committee for Standardisation and the International Organization for Standardization in 2013. As part of the European Mandate No. M381 to validate 15 standards in the field of food microbiology, an international validation study involving 18 laboratories from 11 countries in Europe was conducted between 2012 and 2014. This study aimed to generate method characteristics including limit of detection, limit of quantification, repeatability and reproducibility for ISO 15216 - Part 1, the method for quantification, in seven food matrices. The organization and results of this study, including observations that led to improvements in the standard method are presented here. After its conclusion, the method characteristics generated were added to the revised international standard, ISO 15216-1:2017, published in March 2017.


Assuntos
Microbiologia de Alimentos/métodos , Vírus da Hepatite A/fisiologia , Norovirus/fisiologia , Animais , Bivalves/virologia , União Europeia , Frutas/virologia , Vírus da Hepatite A/genética , Vírus da Hepatite A/isolamento & purificação , Humanos , Limite de Detecção , Norovirus/genética , Norovirus/isolamento & purificação , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Frutos do Mar/virologia , Verduras/virologia
18.
Mar Pollut Bull ; 137: 382-387, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30503447

RESUMO

We determined the abundance and virulence of Vibrio parahaemolyticus in seawater and bivalves from the Gyeongnam coast in Korea, a major area for the seafood industry, during 2004-2016. V. parahaemolyticus is one of the most common pathogen causing seafood-borne illnesses in Korea, and increases during the summer. Its occurrence in seawater and bivalve samples was seasonally dependent, with high levels during the summer to early autumn. There were more strains in the area of sea continually exposed to inland wastewater. Only 5.1% and 3.5% of V. parahaemolyticus isolates from seawater and bivalves, respectively, had the trh gene, and only the bivalve isolates produced the tdh gene at levels below 2%. Continuous monitoring is clearly needed to reduce seafood-borne outbreaks of disease caused by V. parahaemolyticus, and to reveal the occurrence patterns and the presence of toxic genes of the strains in different marine environments.


Assuntos
Bivalves/virologia , Água do Mar/virologia , Frutos do Mar/virologia , Vibrio parahaemolyticus/isolamento & purificação , Animais , Proteínas de Bactérias/genética , Proteínas Hemolisinas/genética , República da Coreia , Estações do Ano , Vibrio parahaemolyticus/genética , Vibrio parahaemolyticus/patogenicidade , Virulência/genética , Águas Residuárias
19.
Biomed Environ Sci ; 31(10): 713-720, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30423272

RESUMO

OBJECTIVE: Shellfish are recognized as important vehicles of norovirus-associated gastroenteritis. The present study aimed to monitor norovirus contamination in oysters along the farm-to-fork continuum in Guangxi, a major oyster production area in Southwestern China. METHODS: Oyster samples were collected monthly from farms, markets, and restaurants, from January to December 2016. Norovirus was detected and quantified by one-step reverse transcription-droplet digital polymerase chain reaction (RT-ddPCR). RESULTS: A total of 480 oyster samples were collected and tested for norovirus genogroups I and II. Norovirus was detected in 20.7% of samples, with genogroup II predominating. No significant difference was observed in norovirus prevalence among different sampling sites. The norovirus levels varied widely, with a geometric mean of 19,300 copies/g in digestive glands. Both norovirus prevalence and viral loads showed obvious seasonality, with a strong winter bias. CONCLUSION: This study provides a systematic analysis of norovirus contamination 'from the farm to the fork' in Guangxi. RT-ddPCR can be a useful tool for detection and quantification of low amounts of norovirus in the presence of inhibitors found particularly in foodstuffs. This approach will contribute to the development of strategies for controlling and reducing the risk of human illness resulting from shellfish consumption.


Assuntos
Contaminação de Alimentos/análise , Norovirus/isolamento & purificação , Ostreidae/virologia , Reação em Cadeia da Polimerase/métodos , Frutos do Mar/virologia , Animais , China
20.
Sci Total Environ ; 643: 1514-1521, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-30189567

RESUMO

Human noroviruses (NoVs) are responsible for 50% of food-related disease outbreaks and are notably associated with shellfish consumption. Despite the detrimental health impacts of human NoV-contaminated seafood to public health, there is a lack of knowledge on the physicochemical conditions that govern NoV transmission in aquatic ecosystems. In the present study, we investigated the propensity for NoVs to associate with aquatic aggregates, which have been shown to efficiently deliver nano-sized particles to shellfish. Specific physicochemical conditions characteristic of shellfish cultivation waters, specifically salinity and transparent exopolymer particles (TEP), were targeted in this study for investigating aggregate formation and NoV association dynamics. Murine norovirus (MNV) was used in aggregation experiments as a model surrogate for NoVs. Results demonstrate increased aggregate formation as a function of increasing salinity and TEP concentrations, as well as greater numbers of MNV genomes incorporated into aggregates under conditions that favor aggregation. As aggregate formation was enhanced in waters representing optimal conditions for shellfish production, specifically saline and high TEP waters, the implications to virus transport and shellfish food safety are profound: more aggregates implies increased scavenging of virus particles from surrounding waters and therefor greater risk for bivalve contamination with nano-sized pathogens. These novel data provide insight into where and when NoVs are most likely to be ingested by shellfish via contaminated aggregates, thereby informing best management and water quality monitoring practices aimed at providing safe seafood to consumers.


Assuntos
Bivalves/virologia , Norovirus , Frutos do Mar/virologia , Animais , Humanos , Camundongos , Polissacarídeos Bacterianos , Salinidade
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