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1.
Int J Food Microbiol ; 344: 109089, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33662900

RESUMO

Contamination of bivalve molluscs with viruses is well recognized as a food safety risk. A microbiological criterion for norovirus (NoV) and hepatitis A virus (HAV) in shellfish, however, does not exist in the European Union currently. The aim of this study was to evaluate the contamination levels of these viruses for fluctuation over a long period (2013-2017) in oyster (n = 266) and mussel samples (n = 490) using a method based on ISO/TS 15216-1: 2013. Samples were taken at different points in the food chain, either directly post-harvest, at Dutch dispatch centers or in retail stores, from September until March of each year. Altogether, 53.1% of the mussel and 31.6% of the oyster samples tested positive for NoV RNA. Simultaneous presence of NoV GI and GII RNA was observed in 31.6% of mussel and 10.2% of oyster samples. Contamination levels in NoV positive mussel samples collected post-harvest from B-areas were significantly higher than in those collected post-harvest from A-areas, or at dispatch centers or retail stores. Levels in oysters from dispatch were significantly lower than those collected in retail stores. Ready for sale mussels and oysters contained 2.04 and 1.76 mean log10 transformed NoV genome copies/gram (gc/g), respectively. GII levels were at a constant level in ready for sale mussels throughout all sampling periods in the study. This seemed to be true for oysters as well. HAV RNA was detected in only one of the tested mussel samples (n = 392) (typed HAV 1A) and in none of the tested oyster samples (n = 228). Critical evaluation of NoV and HAV levels in shellfish can be of help for risk assessment and risk management actions.


Assuntos
Infecções por Caliciviridae/epidemiologia , Vírus da Hepatite A/isolamento & purificação , Hepatite A/epidemiologia , Norovirus/isolamento & purificação , Ostreidae/virologia , Animais , Infecções por Caliciviridae/veterinária , Cadeia Alimentar , Contaminação de Alimentos/análise , Inocuidade dos Alimentos , Hepatite A/veterinária , Vírus da Hepatite A/genética , Humanos , Países Baixos/epidemiologia , Norovirus/genética , Frutos do Mar/virologia
2.
Viruses ; 13(2)2021 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-33573054

RESUMO

Recently, we experienced an outbreak of acute hepatitis A virus (HAV) infection between 2018 and 2020. Herein, we describe this male-dominant HAV infection outbreak observed among non-human immunodeficiency virus (HIV)-infected persons in the northern part of Tokyo, Japan. Clinical information was collected from patient interviews and from medical record descriptions. In the present study, 21 patients were retrospectively analyzed. A total of 90.4 and 33.3% of patients were males, and men who have sex with men (MSM), respectively. The total bilirubin levels and platelet counts tended to be lower in the MSM group than in the non-MSM group. C-reactive protein (CRP) levels tended to be higher in acute liver failure (ALF) patients than in non-ALF patients. Prolonged cholestasis was observed in one patient (4.8%). We also found that 18 HAV isolates belonged to HAV subgenotype IA/subgroup 13 (S13), which clustered with the HAV isolate (KX151459) that was derived from an outbreak of HAV infection among MSM in Taiwan in 2015. Our results suggest that the application of antivirals against HAV, as well as HAV vaccines, would be useful for the treatment and prevention of severe HAV infection.


Assuntos
Surtos de Doenças , Hepatite A/epidemiologia , Adulto , Feminino , Genótipo , Hepatite A/virologia , Vírus da Hepatite A/classificação , Vírus da Hepatite A/genética , Vírus da Hepatite A/isolamento & purificação , Homossexualidade Masculina , Humanos , Tempo de Internação , Falência Hepática Aguda/epidemiologia , Falência Hepática Aguda/virologia , Masculino , Pessoa de Meia-Idade , Filogenia , Estudos Retrospectivos , Fatores de Risco , Minorias Sexuais e de Gênero , Tóquio/epidemiologia
3.
Viruses ; 12(12)2020 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-33352751

RESUMO

Hepatitis A virus (HAV) is a waterborne pathogen of public health importance. In South Africa (SA), unique HAV subgenotype IB strains have been detected in surface and wastewater samples, as well as on fresh produce at the point of retail. However, due to the use of molecular-based assays, the infectivity of the detected strains was unknown. Considering the potential shift of HAV endemicity from high to intermediate, which could increase the risk of severe symptomatic disease, this study investigated the identity of HAV strains detected before and after viability treatment of selected wastewater discharge samples. For one year, 118 samples consisting of sewage, treated wastewater discharge and downstream dam water were collected from five wastewater treatment plants (WWTP 1, 2, 3, 4 and 5). Unique HAV IB strains were detected in samples from all five WWTPs, with 11 of these strains carrying amino acid mutations at the immunodominant and neutralisation epitopes. A quasispecies dynamic of HAV has also been detected in sewage samples. The subsequent application of viability PCR revealed that potentially infectious HAV strains were discharged from WWTP 1, 2, 4 and 5 into the dam. Therefore, there is a potential risk of HAV exposure to communities using water sources downstream the WWTPs.


Assuntos
Vírus da Hepatite A/isolamento & purificação , Esgotos/virologia , Águas Residuárias/virologia , Purificação da Água , Vírus da Hepatite A/genética , Vírus da Hepatite A/imunologia , Filogenia
4.
Ann Agric Environ Med ; 27(3): 481-484, 2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32955233

RESUMO

INTRODUCTION AND OBJECTIVE: Hepatitis A Virus (HAV), reportedly the most common cause of acute viral hepatitis in developing countries, infects millions of people worldwide each year. The aim of the study is to investigate the seropositivity of anti-hepatitis A virus (HAV) IgG and IgM in all age groups in Erzurum, and to determine the effect of various factors such as age, gender, climatic conditions and HAV vaccination (included in 2012 in the National Immunization Schedule on seroprevalence) on the seropositivity. MATERIAL AND METHODS: The serological results of 25,007 individuals referred to Erzurum Public Health Microbiology Laboratory between January 2015 - December 2018 were retrospectively reviewed to test for the presence of anti-HAV IgG and IgM. The patient ages were 0-93 years. Serum samples were analyzed by ELISA. S/CO values of ≥1.00 and >1.21 were considered positive for anti-HAV IgG and IgM, respectively; results below this value were considered negative. RESULTS: Anti-HAV IgG and IgM seropositivities were 87.3% and 0.2%, respectively. Anti-HAV IgG prevalence - 88.5% and 86.4%, anti-HAV IgM positivity - 0.1% and 0.3% in men and women. Anti-HAV IgG seroprevalence - 87%, 73.2%, 58.7%, 75.2%, 86.1%, 89.8%, 96.1%, 99.1%, 99.1% and 99.3%, respectively, at 0-4, 5-9 10-14, 15-19, 20-24, 25-29, 30-39, 40-49, 50-59 and >60 age groups. Anti-HAV IgM seropositivity - 0, 0.1%, 0.7%, 0.7%, 0.3%, 0, 0.1%, 0.2%, 0.1%, and 0.2%, respectively, in the same age groups. Anti-HAV IgM positivity was the highest in November - 36(0.97%. CONCLUSIONS: In Erzurum, anti-HAV IgG prevalence is tremendously high, whereas prevalence of anti-HAV IgM is exceptionally low, especially in the paediatric age group. Therefore, HAV vaccine is provided free of charge in Turkey, including Erzurum, since 2012.


Assuntos
Vírus da Hepatite A/isolamento & purificação , Hepatite A/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Anticorpos Anti-Hepatite A/sangue , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Estudos Soroepidemiológicos , Turquia/epidemiologia , Adulto Jovem
5.
Int J Food Microbiol ; 328: 108661, 2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32454367

RESUMO

Virus detection in food requires appropriate elution and concentration techniques which need to be adapted for different food matrices. ISO/TS-15216-1:2017 and ISO/TS-15216-2:2019 describe standard methods for hepatitis A virus (HAV) research in some food only. Milk-based products containing one or more types of fruit are not covered by ISO procedures, even though they can be contaminated by fruit added to these products or by the food handlers. The aim of this work was to identify an efficient method for the detection of HAV in milk-based products. Four methods were tested to recover HAV from artificially contaminated milk, yoghurt and ice cream containing soft fruits. Results showed that the efficiency of the tested methods depends on the analyzed matrix. In milk we obtained a mean recovery from 13.4% to 1.9%; method based on high speed centrifuge gave the best values. The average recovery in yoghurt was between 3.3% and 114.4%, the latter value achieved by method with beef extract at 3% as eluent. Finally, two methods gave the best results in ice cream with similar recoveries: 29.1% and 27.7% respectively. The first method used glycine as eluent while the other one was based on high speed centrifugation. The ISO method has never proved to be the most efficient in the matrices studied. Therefore, based on the results obtained, a complete rethinking of the ISO method may be necessary to improve its recovery for some products such as milk, while only small changes would be sufficient for other products, such as yoghurt and ice cream.


Assuntos
Contaminação de Alimentos/análise , Frutas/virologia , Vírus da Hepatite A/isolamento & purificação , Sorvetes/virologia , Leite/virologia , Iogurte/virologia , Animais , Bovinos , Manipulação de Alimentos , Microbiologia de Alimentos
6.
J Appl Microbiol ; 129(5): 1120-1132, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32471014

RESUMO

Food contaminated by hepatitis A virus (HAV) is responsible of the 2-7% of all HAV outbreaks worldwide. This review provides a description of the HAV characteristics, its infectivity and epidemiological features. In addition, this review compiles existing original papers reporting HAV prevalence, viral titres in foodstuffs and the risk associated with food contamination. The purpose of this revision is to conduct a structured and systematic review of the published molecular procedures for HAV detection in food, including the assessment of its infectivity.


Assuntos
Microbiologia de Alimentos , Doenças Transmitidas por Alimentos/virologia , Vírus da Hepatite A/isolamento & purificação , Vírus da Hepatite A/fisiologia , Hepatite A/transmissão , Surtos de Doenças/estatística & dados numéricos , Contaminação de Alimentos/análise , Doenças Transmitidas por Alimentos/epidemiologia , Hepatite A/epidemiologia , Hepatite A/virologia , Humanos , Prevalência , Medição de Risco
8.
Mikrochim Acta ; 187(2): 140, 2020 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-31955258

RESUMO

Molecularly imprinted polymer (HM@MIP) nanoprobes were designed form the pH-responsive polymer (dimethylaminoethyl methacrylate (DMA)) and MIL-101. This probe was applied to the selective determination of hepatitis A virus (HAV) through Resonance light scattering (RLS) technique. DMA adjusts pH of the system to facilitate the capture and release of virus by HM@MIPs as anticipated. And it results in the enhancement or weaken of RLS intensity. According to RLS intensity at 470 nm, a linear concentration of 0.02-2.0 nmol·L-1 and a limit of detection of 0.1 pmol·L-1 were obtained within 20 min. The excellent recoveries ranges from 88% to 107%, and it indicates the prominent ability of the HM@MIPs to determination HAV in human serum and their potential ability to determination virus in real applications. Graphical abstractPrinciple of preparation of the HM@MIPs and detection of virus.


Assuntos
Vírus da Hepatite A/isolamento & purificação , Luz , Estruturas Metalorgânicas , Impressão Molecular/métodos , Nanopartículas/química , Espalhamento de Radiação , Humanos , Concentração de Íons de Hidrogênio , Limite de Detecção , Estruturas Metalorgânicas/química , Polímeros , Ácidos Polimetacrílicos/química
9.
J Infect Chemother ; 26(2): 282-285, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31543437

RESUMO

Hepatitis A virus (HAV) commonly causes acute hepatitis in humans and is transmitted through the fecal-oral route or by ingestion of contaminated food or water. HAV infection generally follows a self-limiting course; it can seldom cause fulminant hepatitis that increases the risk of mortality. To the best of our knowledge, this is the first reported fatal case of fulminant hepatitis caused by HAV in a 40-year-old male with human immunodeficiency virus (HIV) infection. The HAV genotype in this case was IA, which has recently become common globally among people living with HIV (PLWHIV), intravenous drug users, and homeless people especially in developed countries. His HIV infection was stabilized by antiretroviral drugs and his CD4 values were stable. He developed acute hepatic encephalopathy, did not respond to repeated plasma exchange therapy, and died rapidly. It is known that HIV co-infection sometimes leads to fulminant non-HAV hepatitis, although evidence supporting a correlation between fulminant hepatitis A risk and HIV infection is still lacking. This case demonstrated the fatal risk of HAV infection in PLWHIV; it was suggested that education about appropriate preventive measures and vaccination are important for preventing HAV infections among PLWHIV.


Assuntos
Coinfecção , Infecções por HIV/complicações , Hepatite A/complicações , Necrose Hepática Massiva/etiologia , Adulto , Evolução Fatal , Encefalopatia Hepática/etiologia , Encefalopatia Hepática/virologia , Vírus da Hepatite A/isolamento & purificação , Anticorpos Anti-Hepatite B/sangue , Humanos , Masculino , Necrose Hepática Massiva/virologia , Vacinação
10.
Arch Virol ; 165(3): 715-718, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31873766

RESUMO

In the present study, we evaluated the degree of contamination of fresh vegetables, cheeses and jellies from disaster area in Brazil with bacteria and enteric viruses. Food samples (n = 350) were tested for Escherichia coli, Salmonella spp., Listeria monocytogenes, Staphylococcus spp., and enteric viruses (rotavirus A (RVA), human adenovirus (HAdV), hepatitis A virus (HAV), and human norovirus (HNoV). E. coli was present in 56% of the samples, Salmonella spp. was present in 14% of the samples, L. monocytogenes and Staphylococcus spp. (coagulase-positive) were present in 36% of the samples. The enteric viruses RVA and HAdV were detected in cheeses and vegetables.


Assuntos
Queijo/microbiologia , Contaminação de Alimentos/análise , Verduras/microbiologia , Adenovírus Humanos/isolamento & purificação , Brasil , Escherichia coli/isolamento & purificação , Fazendas , Vírus da Hepatite A/isolamento & purificação , Humanos , Listeria monocytogenes/isolamento & purificação , Norovirus/isolamento & purificação , Rotavirus/isolamento & purificação , Salmonella/isolamento & purificação , Staphylococcus/isolamento & purificação
11.
Anal Chem ; 91(24): 15748-15756, 2019 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-31718158

RESUMO

Simultaneous detection of large viruses has been a great obstacle in the field of molecular imprinting. In this work, for the first time, a multifunctional molecularly imprinted sensor for single or simultaneous determination of hepatitis A virus (HAV) and hepatitis B virus (HBV) is provided. Visual detection was realized due to the color of green and red quantum dots that varied with the concentration of the target substance. The combination of hydrophilic monomers and metal chelation reduced the nonspecific binding and enhanced the specificity of adsorption. As a result, satisfactory selectivity and sensitivity were obtained for the detection of the two viruses, with imprinting factors of 3.70 and 3.35 for HAV and HBV, and limits of detection of 3.4 and 5.3 pmol/L, respectively, that were achieved within 20 min. The excellent recoveries during simultaneous detection and single detection modes indicate the prominent ability of the proposed sensor to detect HAV and HBV in human serum and the potential ability to simultaneously detect multiple viruses in real applications.


Assuntos
Técnicas Biossensoriais/métodos , Corantes Fluorescentes/química , Vírus da Hepatite A/isolamento & purificação , Hepatite A/sangue , Vírus da Hepatite B/isolamento & purificação , Hepatite B/sangue , Impressão Molecular/métodos , Compostos de Cádmio/química , Hepatite A/diagnóstico , Hepatite A/virologia , Hepatite B/diagnóstico , Hepatite B/virologia , Humanos , Limite de Detecção , Polímeros/química , Pontos Quânticos , Telúrio/química
12.
Int J Food Microbiol ; 311: 108349, 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31634688

RESUMO

Food-borne viral infections are caused mainly by noroviruses (NoV) and the hepatitis A virus (HAV), which respectively cause gastroenteritis and hepatitis. Various foods have been implicated in viral outbreaks, including vegetables that are consumed in a variety of forms, often with salad dressing. NF EN ISO procedures (15216-1:2017) propose standard methods for quantifying NoV and HAV in high-risk food categories, such as vegetables, based on viral elution and PEG concentration methods, but these methods are not suitable for composite meals like salads dressed with oily, fatty or emulsified food ingredients. The development of sensitive and reliable techniques for the detection of viruses in these products is therefore needed to ensure the safety of these products. The aim of this study was to develop an RT-qPCR based method for the detection and quantification of NoV and HAV in various vegetables with different dressings. Three methods for recovering NoV and HAV from artificially contaminated dressed vegetables were evaluated. The selected method was based on the use of Trizol reagent and, according to the type of dressing, the limit of detection ranged from 104 to 106 genome copies/g for NoV and from 102 to 103 PFU/g for HAV. The described method can be applied for detecting NoV and HAV in food containing salad dressing for routine diagnosis needs.


Assuntos
Contaminação de Alimentos/análise , Microbiologia de Alimentos/métodos , Vírus da Hepatite A/isolamento & purificação , Norovirus/isolamento & purificação , Verduras/virologia , Doenças Transmitidas por Alimentos/prevenção & controle , Doenças Transmitidas por Alimentos/virologia , Gastroenterite/prevenção & controle , Gastroenterite/virologia , Genoma Viral/genética , Vírus da Hepatite A/genética , Humanos , Norovirus/genética , RNA Viral/análise , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa
13.
Int J Food Microbiol ; 309: 108327, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31493567

RESUMO

The apparent international rise in foodborne virus outbreaks attributed to fresh produce and the increasing importance of fresh produce in the Australian diet has led to the requirement to gather information to inform the development of risk management strategies. A prevalence survey for norovirus (NoV) and hepatitis A virus (HAV) in fresh Australian produce (leafy greens, strawberries and blueberries) at retail was undertaken during 2013-2014 and data used to develop a risk profile. The prevalence of HAV in berries and leafy greens was estimated to be <2%, with no virus detected in produce during the yearlong survey. The prevalence of NoV in fresh strawberries and blueberries was also estimated to be <2% with no virus detected in berries, whilst for leafy greens the NoV prevalence was 2.2%. Prevalence of a bacterial hygiene indicator, Escherichia coli, was also investigated and found to range from <1% in berries to 10.7% in leafy greens. None of the NoV positive leafy green samples tested positive for E. coli, indicating it is a poor indicator for viral risk. The risk was evaluated using standard codex procedures and the Risk Ranger tool. Taking all data into account, including the hazard dose and severity, probability of exposure, probability of infective dose and available epidemiological data, the risk of HAV and NoV foodborne illness associated with fresh Australian berries (strawberries and blueberries) sold as packaged product was deemed to be low. The risk of foodborne illness from HAV associated with leafy greens was also deemed to be low, but higher than that for fresh berries, due mainly to the potential for recontamination post-processing if sold loose. The risk of foodborne illness from NoV associated with leafy greens was deemed to be low/moderate. Despite the prevalence of NoV in leafy greens being low and the inability to discriminate between infective and non-infective virus using PCR based methodologies, the fact that NoV was detected resulted in a higher risk associated with this pathogen-product pairing; compounded by the higher prevalence of NoV within the community compared to HAV, and the potential for leafy greens to become contaminated following processing if sold loose.


Assuntos
Mirtilos Azuis (Planta)/microbiologia , Doenças Transmitidas por Alimentos/epidemiologia , Fragaria/microbiologia , Frutas/virologia , Vírus da Hepatite A/isolamento & purificação , Norovirus/isolamento & purificação , Austrália/epidemiologia , Surtos de Doenças , Escherichia coli/isolamento & purificação , Doenças Transmitidas por Alimentos/microbiologia , Humanos , Folhas de Planta/microbiologia , Probabilidade
14.
Food Environ Virol ; 11(4): 393-399, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31420848

RESUMO

Enteroviruses (EVs) and Hepatitis A Viruses (HAVs) are human pathogens with a wide spectrum of clinical manifestations. The monitoring of sewage samples enables to monitor the EVs and HAVs in circulation among the general population and recognize possible outbreaks. This study focused on the molecular characterization and phylogenetic analysis of the EVs and HAVs identified in 33 sewage samples collected every 15 days at the influent of a wastewater treatment plant located in Northern Italy from March to October 2016. According to the results of the molecular characterization, the most frequently identified viruses were Echovirus 6 (E-6), E-11 and HAV-IA. The phylogenetic analyses indicated the rapid genetic evolution of E-6 and E-1; noteworthy, most E-11 strains clustered with a strain isolated from a clinical sample collected in the same geographical area over the same period by our laboratory. Most of the HAV strains detected clustered with epidemic HAV-IA strains identified during the European hepatitis A outbreak that occurred in 2016-2017 affecting men who have sex with men (MSM). The detection of environmental HAV strains before and at the beginning of its spread amongst humans demonstrated that this outbreak could have been predicted by monitoring sewage samples. Moreover, conducting a genetic comparison between the HAV and EV strains identified in sewage and clinical samples may improve knowledge of viral epidemiology. EV and HAV molecular environmental surveillance may prove useful for identifying viral circulation and for issuing early warning alerts on possible outbreaks among the human population.


Assuntos
Infecções por Enterovirus/virologia , Enterovirus/genética , Vírus da Hepatite A/genética , Hepatite A/virologia , Filogenia , Esgotos/virologia , Enterovirus/classificação , Enterovirus/isolamento & purificação , Infecções por Enterovirus/epidemiologia , Hepatite A/epidemiologia , Vírus da Hepatite A/classificação , Vírus da Hepatite A/isolamento & purificação , Humanos , Itália/epidemiologia
15.
Food Microbiol ; 84: 103236, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31421754

RESUMO

Hepatitis A virus (HAV) continues to be the leading cause of viral hepatitis. HAV outbreaks have been linked to the consumption of milk, but methods for HAV detection in milk are very limited. We developed a method to concentrate HAV in milk using protamine-coated iron oxide (Fe3O4) magnetic nanoparticles (PMNPs). In this study, protamine was covalently coated on the surface of the MNPs (20-30 nm) by a three-step chemical reaction. The successful linkage of protamine to the MNPs was confirmed by Fourier transform infrared spectroscopy (FTIR), zeta potential, and transmission electron microscopy (TEM). When used for concentrating HAV from 40 mL of milk, 50 µL of PMNPs were added to the sample and mixed for 20 min by gentle rotation, followed by a magnet capture for 30 min. The captured PMNPs were washed with glycine buffer (0.05 M glycine, 0.14 M NaCl, 0.2% (v/v) Tween 20, pH 9.0) and HAV RNA was extracted using the QIAamp MinElute Virus Spin Kit and quantified by real-time RT-PCR. The method showed a detection limit of 8.3 × 100 PFU of HAV in milk. The whole concentration procedure could be completed in approximately 50 min. The developed method was simple, inexpensive, and easy-to-perform.


Assuntos
Compostos Férricos/química , Microbiologia de Alimentos/métodos , Vírus da Hepatite A/isolamento & purificação , Leite/virologia , Protaminas/química , Animais , Limite de Detecção , Nanopartículas de Magnetita , RNA Viral
16.
Food Microbiol ; 84: 103257, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31421763

RESUMO

The viability of murine norovirus (MNV-1), bovine rotavirus (boRV), and hepatitis A virus (HAV) was evaluated at 21 °C, 4 °C, and -20 °C on stainless steel surfaces, in bottled water, and on blueberries for up to 21 days. After 14 days of incubation at 21 °C on stainless steel, a viability loss >4 log for MNV-1, >8 log for boRV, and >1 log for HAV was observed. Losses were observed for MNV-1 (>1 log) and HAV (>2 log) incubated in water at 21 °C for 21 days. No significant loss was detected for MNV-1 and HAV at 4 °C and -20 °C and for boRV at 21 °C, 4 °C, and -20 °C. On blueberries incubated at 4 °C and -20 °C, they all maintained their infectivity. After 7 days at 21 °C, a loss >2 log, a loss of 3 log, and no loss were observed for boRV, MNV-1, and HAV, respectively. After RNase pretreatment, the detection of extracted RNA from infectious and noninfectious samples suggested the protection of RNA inside the capsid. Even though they all are enteric viruses, their persistence varied with temperature and the nature of the commodity. It is therefore important to use more than one viral surrogate, during inactivation treatments or implementation of control measures.


Assuntos
Mirtilos Azuis (Planta)/virologia , Água Potável/microbiologia , Vírus da Hepatite A/isolamento & purificação , Norovirus/isolamento & purificação , Rotavirus/isolamento & purificação , Aço Inoxidável/análise , Inativação de Vírus , Animais , Bovinos , Linhagem Celular , Desinfecção , Contaminação de Alimentos/análise , Vírus da Hepatite A/genética , Camundongos , Norovirus/genética , RNA Viral , Rotavirus/genética , Temperatura
17.
Epidemiol Infect ; 147: e210, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-31364560

RESUMO

India is experiencing a substantial decrease in early childhood exposure to hepatitis A virus (HAV). Kerala has experienced several hepatitis A outbreaks in young adults/adults in the recent past. The current hepatitis outbreak occurred in Nellikuzhi, Kerala state, India in December 2016. Investigation was carried by preparing a line list of suspected hepatitis cases. The blood and stool samples collected from patients were tested for anti-HAV/anti-Hepatitis E virus (HEV) immunoglobulin (IgM) antibodies and RNA respectively. A total of 562 suspected hepatitis cases were reported during the outbreak. Along with the first case (35 years, male), 86.1% (484/562) of the cases gave history of consuming food/water/cold drinks from one restaurant. Anti-HAV IgM positivity was 74.5% (73/98) in tested samples and amongst the positives, 81% were adults/young adults and adolescents. None of the samples tested positive for anti-HEV IgM. There were three HAV associated deaths without any co-morbidity. Sequence analysis of HAV RNA positive stool samples showed the presence of genotype IIIA HAV. The suspected source of the infection was a private well situated in the premise of a restaurant. Considering increasing HAV naive population in Kerala, there is a need to introduce hepatitis A vaccine in high-risk age groups.


Assuntos
Transmissão de Doença Infecciosa , Doenças Transmitidas por Alimentos/epidemiologia , Vírus da Hepatite A/isolamento & purificação , Hepatite A/epidemiologia , Hepatite A/transmissão , Restaurantes , População Rural , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Fezes/virologia , Feminino , Genótipo , Anticorpos Anti-Hepatite A/sangue , Vírus da Hepatite A/classificação , Vírus da Hepatite A/genética , Vírus da Hepatite A/imunologia , Humanos , Imunoglobulina M/sangue , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , RNA Viral/análise , RNA Viral/genética , Análise de Sobrevida , Adulto Jovem
18.
Epidemiol Infect ; 147: e226, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-31364583

RESUMO

To control hepatitis A spread by vaccination, accurate estimation of transmissibility is vital. Regan et al. (2016) proposed a model of hepatitis A virus (HAV) transmission and used least squares to calibrate model to the 1991/1992 HAV outbreak in men who have sex with men (MSM) in Sydney, Australia. Based on the estimate of R0, they obtained the critical immunity of 70% and showed that when the proportion immune <70%, there is a definite chance for outbreaks to take place. The immunity level from previous surveys ranges from 32% to 64% after 1996 while no outbreaks in Australian MSMs have been reported since 1996. Further noticing the ill-distributed parameters, we argue that their estimate of R0 is not accurate. In this study, we revisited their model by Bayesian inference, which has privilege over least squares. We obtained the appropriate posterior distributions of parameters and the estimate of R0 ranges from 1.38 to 2.89, indicating a critical immunity of 65%. The reduction in critical immunity and outbreak probabilities predicts the absence of outbreaks in Australian MSMs since 1996. Our study shows the importance of using appropriate methods to provide reliable and accurate estimates of the model parameters especially the transmissibility.


Assuntos
Controle de Doenças Transmissíveis , Surtos de Doenças , Transmissão de Doença Infecciosa/estatística & dados numéricos , Vírus da Hepatite A/isolamento & purificação , Hepatite A/epidemiologia , Homossexualidade Masculina/estatística & dados numéricos , Adulto , Austrália/epidemiologia , Teorema de Bayes , Estudos de Coortes , Transmissão de Doença Infecciosa/prevenção & controle , Hepatite A/diagnóstico , Humanos , Masculino , Cadeias de Markov , Estudos Retrospectivos , População Urbana
19.
Emerg Infect Dis ; 25(8): 1594-1596, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31310213

RESUMO

We implemented subgenomic and whole-genome sequencing to support the investigation of a large hepatitis A virus outbreak among persons experiencing homelessness, users of illicit drugs, or both in California, USA, during 2017-2018. Genotyping data helped confirm case-patients, track chains of transmission, and monitor the effectiveness of public health control measures.


Assuntos
Vírus da Hepatite A/classificação , Vírus da Hepatite A/genética , Hepatite A/epidemiologia , Hepatite A/virologia , Tipagem Molecular , California/epidemiologia , Surtos de Doenças , Genótipo , Hepatite A/história , Hepatite A/transmissão , Vírus da Hepatite A/imunologia , Vírus da Hepatite A/isolamento & purificação , História do Século XXI , Humanos , Vigilância em Saúde Pública , Proteínas Virais/genética , Sequenciamento Completo do Genoma
20.
Euro Surveill ; 24(28)2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31311618

RESUMO

IntroductionSequence-based typing of hepatitis A virus (HAV) is important for outbreak detection, investigation and surveillance. In 2013, sequencing was central to resolving a large European Union (EU)-wide outbreak related to frozen berries. However, as the sequenced HAV genome regions were only partly comparable between countries, results were not always conclusive.AimThe objective was to gather information on HAV surveillance and sequencing in EU/European Economic Area (EEA) countries to find ways to harmonise their procedures, for improvement of cross-border outbreak responses.MethodsIn 2014, the European Centre for Disease Prevention and Control (ECDC) conducted a survey on HAV surveillance practices in EU/EEA countries. The survey enquired whether a referral system for confirming primary diagnostics of hepatitis A existed as well as a central collection/storage of hepatitis A cases' samples for typing. Questions on HAV sequencing procedures were also asked. Based on the results, an expert consultation proposed harmonised procedures for cross-border outbreak response, in particular regarding sequencing. In 2016, a follow-up survey assessed uptake of suggested methods.ResultsOf 31 EU/EEA countries, 23 (2014) and 27 (2016) participated. Numbers of countries with central collection and storage of HAV positive samples and of those performing sequencing increased from 12 to 15 and 12 to 14 respectively in 2016, with all countries typing an overlapping fragment of 218 nt. However, variation existed in the sequenced genomic regions and their lengths.ConclusionsWhile HAV sequences in EU/EEA countries are comparable for surveillance, collaboration in sharing and comparing these can be further strengthened.


Assuntos
Surtos de Doenças/prevenção & controle , Vírus da Hepatite A/isolamento & purificação , Hepatite A/diagnóstico , Tipagem Molecular/métodos , Vigilância da População/métodos , Sequenciamento Completo do Genoma/métodos , Europa (Continente)/epidemiologia , União Europeia , Hepatite A/epidemiologia , Vírus da Hepatite A/genética , Humanos , RNA Viral/análise , Análise de Sequência de DNA
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