Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| [probe types of norwalk-like viruses genome detected by rt-pcr with seven primer pairs in yamanashi prefecture]. | the reverse transcription-polymerase chain reaction (rt-pcr) gene assay, as well as electron microscopic examination, is commonly used to detect norwalk-like viruses (nlvs). types and number of primer pairs used are considered to be of critical importance for efficiency of the rt-pcr detection. this study was performed to determine primer pairs useful for the detection of nlvs. nlvs genes were detected by rt-pcr in 48 cases in yamanashi prefecture between december 1997 and march 2000. the probe ... | 2000 | 10965659 |
| molecular cloning, expression, and antigenicity of seto virus belonging to genogroup i norwalk-like viruses. | the viral capsid protein of the seto virus (sev), a japanese strain of genogroup i norwalk-like viruses (nlvs), was expressed as virus-like particles using a baculovirus expression system. an antigen detection enzyme-linked immunosorbent assay based on hyperimmune antisera to recombinant sev was highly specific to homologous sev-like strains but not heterologous strains in stools, allowing us type-specific detection of nlvs. | 2000 | 10970413 |
| foodborne infections vectored by molluscan shellfish. | foodborne diseases cause approximately 76 million illnesses, 325,000 hospitalizations, and 5000 deaths each year in the united states. the authors present and analyze information derived from epidemiologic investigations and surveillance systems on foodborne infections caused by consumption of molluscan shellfish. this review focuses on the bias in reporting of shellfish-vectored illness, prevention and control of such infections, the origin of recognized viral and bacterial etiologic agents, an ... | 2000 | 10981028 |
| evidence for airborne transmission of norwalk-like virus (nlv) in a hotel restaurant. | an outbreak of gastroenteritis followed a meal in a large hotel during which one of the diners vomited. the clinical features of the illness suggested norwalk-like virus (nlv, small round structured virus) infection, and this was confirmed by electron microscopy and reverse transcriptase polymerase chain reaction (rt-pcr) of stool samples. further characterization of the virus by nucleotide sequence analysis of the pcr amplicons revealed identical strains in all the affected individuals. the foo ... | 2000 | 10982072 |
| detection of small round structured viruses in stool specimens from outbreaks of gastroenteritis by electron microscopy and reverse transcription-polymerase chain reaction. | in testing 60 stool specimens small round structured virus (srsv) particles were detected in 35 (58%) specimens from all 17 outbreaks of gastroenteritis by electron microscopy (em), while srsv genes were found in 36 (60%) specimens from 15 outbreaks by reverse transcription-polymerase chain reaction (rt-pcr) by use of 2 primer pairs. specimens from 2 outbreaks were found srsv particles-positive by em but srsv genes-negative by rt-pcr. em remains the basic examination method for diagnosis of srsv ... | 2000 | 10989693 |
| [magnitude of rainfall on viral contamination of the marine environment during gastroenteritis epidemics in human coastal population]. | sewage treatments are not efficient to eliminate enteric microorganisms. viruses are able to persist and are discharged into the marine environment with treated effluents. few data are now available on the magnitude and the contributive processes of marine viral contamination. this work evaluates the relationship between the magnitude of rainfall and the viral contamination of the marine environment during winter epidemics of gastroenteritis in human coastal populations. | 2000 | 10992111 |
| rt-pcr identification and typing of astroviruses and norwalk-like viruses in hospitalized patients with gastroenteritis: evidence of nosocomial infections. | astroviruses (hastvs) and 'norwalk-like viruses' (nlv) are frequent causes of gastroenteritis worldwide, though no data on the strains in circulation or their prevalence is available for france. | 2000 | 10996111 |
| direct inhibitory effect of rotavirus nsp4(114-135) peptide on the na(+)-d-glucose symporter of rabbit intestinal brush border membrane. | the direct effect of a rotavirus nonstructural glycoprotein, nsp4, and certain related peptides on the sodium-coupled transport of d-glucose and of l-leucine was studied by using intestinal brush border membrane vesicles isolated from young rabbits. kinetic analyses revealed that the nsp4(114-135) peptide, which causes diarrhea in young rodents, is a specific, fully noncompetitive inhibitor of the na(+)-d-glucose symporter (sglt1). this interaction involves three peptide-binding sites per carrie ... | 2000 | 11000215 |
| prevalence and genetic diversity of human caliciviruses (hucvs) in mexican children. | human caliciviruses (hucvs) contain two genera: "norwalk-like viruses" (nlvs) and "sapporo-like viruses" (slvs). the importance of the two genera as a cause of acute gastroenteritis of infants and children remains unknown. beginning in 1989, a birth cohort of children in mexico was enrolled and monitored for acute gastroenteritis. a subset of 115 diarrhea stool specimens from 76 children and 66 non-diarrhea stool specimens from 64 children was examined for hucvs by rt-pcr by using a primer pair ... | 2000 | 11002251 |
| simplified procedure for detection of enteric pathogenic viruses in shellfish by rt-pcr. | epidemiological evidence linking the transmission of enteric viral disease to shellfish has been known for a long time. a variety of methods have been described for the detection of viral contaminants in shellfish using rt-pcr. however, these methods generally include numerous, often fastidious and time consuming steps for virus release from shellfish tissues and viral rna isolation. a simplified procedure based on the enzymatic liquefaction of shellfish digestive tissues without any mechanical ... | 2000 | 11011076 |
| development of an immunomagnetic capture reverse transcription-pcr assay for the detection of norwalk virus. | norwalk virus (nv) is the prototype human virus of the family caliciviridae. a rapid immunomagnetic capture/reverse transcription-(imc/rt-)pcr assay was developed for the detection of nv. immunomagnetic capture (imc) utilizes paramagnetic beads coupled to a virus-specific antibody and allows separation of virus from contaminating materials and virus concentration in a single step. the detection limit of the developed assay was approximately 250-750 genomic equivalents/ml of 10% stool suspension. ... | 2000 | 11011082 |
| expression of recombinant capsid proteins of chitta virus, a genogroup ii norwalk virus, and development of an elisa to detect the viral antigen. | the second open reading frame (orf2) gene of the chitta virus (chv) was cloned to construct a recombinant baculovirus. the chv orf2 is predicted to encode a capsid protein of 535 amino acids (aa). chv showed a high aa identity in the capsid region with genogroup ii norwalk virus (nv) (65-85%), but a low aa identity with genogroup i nv (44-46%). phylogenetic analysis of the orf2 gene demonstrated that chv is genetically closely related to the hawaii virus included in genogroup ii nv. the recombin ... | 2000 | 11021399 |
| three nursing home outbreaks of norwalk-like virus in brisbane in 1999. | we report on three nursing home outbreaks of gastroenteritis in brisbane in 1999. the presence of norwalk-like virus (nlv) genogroup 2 was demonstrated by reverse transcription polymerase chain reaction (rt-pcr) in all three outbreaks. common findings of these investigations were rapid spread of the illness within the institutions and difficulties in identifying a common source. nursing home populations are vulnerable and it is important for each institution to have infection control policies in ... | 2000 | 11022388 |
| widespread environmental contamination with norwalk-like viruses (nlv) detected in a prolonged hotel outbreak of gastroenteritis. | a protracted outbreak of norwalk-like virus (nlv)-associated gastroenteritis occurred in a large hotel in north-west england between january and may 1996. we investigated the pattern of environmental contamination with nlv in the hotel during and after the outbreak. in the ninth week, 144 environmental swabs taken from around the hotel were tested for nlv by nested rt-pcr. the sites were categorized according to the likelihood of direct contamination with vomit/faeces. the highest proportion of ... | 2000 | 11057964 |
| transmission of norwalk virus during football game. | during a college football game in florida, diarrhea and vomiting developed in many of the members of a north carolina team. the next day, similar symptoms developed in some of the players on the opposing team. | 2000 | 11071673 |
| norwalk virus strikes in pocahontas county. | 2000 | 11077545 | |
| norwalk-like virus sequences detected by reverse transcription-polymerase chain reaction in mineral waters imported into or bottled in switzerland. | norwalk-like viruses (nlvs) is a genus belonging to the caliciviridae. nlvs are transmitted by the fecal-oral and the aerosol route and are the most common cause of outbreaks of nonbacterial gastroenteritis. nlvs are responsible for an estimated 67% of all illnesses caused by known foodborne pathogens and for 96% of nonbacterial gastroenteritis in the united states. many outbreaks could be associated with the consumption of primarily or secondarily contaminated foods. to our knowledge, no epidem ... | 2000 | 11079703 |
| mechanism of capsid assembly for an icosahedral plant virus. | capsids of spherical viruses share a common architecture: an icosahedral arrangement of identical proteins. we suggest that there may be a limited number of common assembly mechanisms for such viruses. previous assembly mechanisms were proposed on the basis of virion structure but were not rigorously tested. here we apply a rigorous analysis of assembly to cowpea chlorotic mottle virus (ccmv), a typical, small, positive-strand rna virus. the atomic resolution structure of ccmv revealed an interl ... | 2000 | 11080492 |
| pcr detection of human enteric viruses in bathing areas, waste waters and human stools in southwestern france. | detection of human pathogenic viruses by molecular techniques might be suitable for identifying viral pollution in environmental waters and for improving diagnosis in patients. environmental samples were taken from bathing areas and sewage treatment plants in southwestern france. small volume samples (50 microl) were tested. five groups of enteric pathogenic viruses were studied: enteroviruses, norwalk-like viruses (nlvs), hepatitis a virus, rotaviruses and adenoviruses. moreover, human samples ... | 2000 | 11081583 |
| interaction of recombinant norwalk virus particles with the 105-kilodalton cellular binding protein, a candidate receptor molecule for virus attachment. | norwalk virus (nv), responsible for outbreaks of acute gastroenteritis, comprises the species of the genus norwalk-like viruses in the family caliciviridae. although the study of the molecular biology of nv has been hampered by a lack of culture systems or small experimental animal models, virus-like particles (vlps) generated with recombinant baculoviruses harboring the capsid protein gene of nv provide a useful tool for investigating nv-cell interactions. in this study, the attachment of the r ... | 2000 | 11090157 |
| complete nucleotide sequence of the chiba virus genome and functional expression of the 3c-like protease in escherichia coli. | we cloned the genome rna of the chiba virus (chv; hu/nlv/chiba 407/1987/jp) and determined its complete nucleotide sequence. the genome is predicted to be a positive-sense, single-stranded rna of 7697 bases, excluding a poly(a) tract. comparison of the nucleotide and amino acid sequences with those of other members of the species norwalk virus (nv) revealed that chv belongs to genogroup i nv. the chv genome contains three open reading frames (orfs). a large 5'-terminal orf (orf1) encodes a polyp ... | 2000 | 11118371 |
| an improved method for the detection of norwalk-like caliciviruses in environmental samples. | an original magnetic beads rna capture was developed for the detection of norwalk-like virus by rt-pcr. the same oligonucleotide was used both for capture and reverse transcription of the viral rna. the optimization studies showed that the most important parameter for sensitivity is the biotin-binding capacity of the beads. this method was found to be efficient for eliminating inhibitors in sewage samples compared with the classic rt-pcr. moreover, the sensitivity was greatly enhanced, allowing ... | 2000 | 11123547 |
| detection methods for human enteric viruses in representative foods. | although viral foodborne disease is a significant problem, foods are rarely tested for viral contamination, and when done, testing is limited to shellfish commodities. in this work, we report a method to extract and detect human enteric viruses from alternative food commodities using an elution-concentration approach followed by detection using reverse transcription-polymerase chain reaction (rt-pcr). fifty-gram lettuce or hamburger samples were artificially inoculated with poliovirus type 1 (pv ... | 2000 | 11131900 |
| immunomagnetic separation of a norwalk-like virus (genogroup i) in artificially contaminated environmental water samples. | rabbit polyclonal antibodies were raised against a recombinant capsid protein from a genogroup i norwalk-like virus (nlv). magnetic beads coated with these antibodies were used in immunomagnetic separation (ims) of the nlv. after capture of the nlv and washing of the beads, viral rna was heat released and detected by rt-pcr. this ims procedure was shown to have high sensitivity for detection of homologous nlv, while capture of a genogroup ii nlv was less efficient. antigen capture was not influe ... | 2000 | 11139018 |
| characterization of monoclonal antibodies generated against norwalk virus gii capsid protein expressed in escherichia coli. | the norwalk virus (nv) causes outbreaks of acute non-bacterial gastroenteritis in humans. the virus capsid is composed of a single 60 kda protein. the capsid protein of nv36 (genogroup ii, mexico virus type) was expressed in an escherichia coli system and ten monoclonal antibodies (mabs) were generated against it. the reactivity of these mabs was characterized using enzyme-linked immunosorbent assay (elisa) and western blot (wb) analysis towards 20 overlapping fragments of the nv36 capsid protei ... | 2000 | 11145271 |
| diagnosis of noncultivatable gastroenteritis viruses, the human caliciviruses. | gastroenteritis is one of the most common illnesses of humans, and many different viruses have been causally associated with this disease. of those enteric viruses that have been established as etiologic agents of gastroenteritis, only the human caliciviruses cannot be cultivated in vitro. the cloning of norwalk virus and subsequently of other human caliciviruses has led to the development of several new diagnostic assays. antigen detection enzyme immunoassays (eias) using polyclonal hyperimmune ... | 2001 | 11148001 |
| [surveillance of group illnesses with norwalk-like viruses (nlv) in baden-württemberg. isolation and detection of norwalk-like viral rna from fecal samples with rt-pcr]. | between the turn of the years 98/99 and 99/2000, stool samples from various health departments in the south of germany were sent to the lga (landesgesundheitsamt baden-württemberg). different testings as bacteriological routines for enterobacteriaceae and virological antigen screenings of the stool samples for adeno-, astro- and rotaviruses lead to negative results. additional rt-pcr tests for the presence of norwalk-rna showed nearly 40% of positive samples. from 14 group infections between dec ... | 2000 | 11151704 |
| development of a reverse transcription-pcr-dna enzyme immunoassay for detection of "norwalk-like" viruses and hepatitis a virus in stool and shellfish. | outbreaks of food- and waterborne gastroenteritis are being increasingly reported throughout the world. the analysis of environmental samples by newer diagnostic techniques such as reverse transcription-pcr (rt-pcr) amplification of nucleic acid has begun to identify human enteric viruses (predominantly "norwalk-like" viruses [nlvs]) as the cause of many of these outbreaks. to streamline nlv detection from environmental samples such as shellfish, we have developed an rt-pcr-oligoprobe amplificat ... | 2001 | 11157239 |
| characterization of "norwalk-like viruses" and astroviruses by liquid hybridization assay. | "norwalk-like viruses" (nlvs) and human astroviruses are causative agents of gastroenteritis in all age-groups. the typing of these agents is generally done by nucleotide sequencing, blot hybridization, or enzyme immunoassay. these techniques are expensive, time-consuming, and sometimes require scarce reagents, which limits the typing of nlvs and astroviruses to a few reference laboratories. this report describes a liquid hybridization assay that uses broadly reactive probes whose sequences are ... | 2001 | 11164493 |
| detection of 'norwalk-like viruses' in vellore, southern india. | 2000 | 11198656 | |
| multiple outbreaks of norwalk-like virus gastro-enteritis associated with a mediterranean-style restaurant. | the role of diverse infectious agents, particularly norwalk-like viruses (nlv), in three successive gastro-enteritis outbreaks in one setting (a restaurant) was evaluated. methods included standard bacteriological tests, specific tests for escherichia coli, tests for verocytotoxins, electron microscopy (em) for viruses and reverse transcription-pcr (rt-pcr) methodology for nlv. no pathogenic bacteria were detected. verocytotoxin genes, although detected by pcr in the first outbreak, could not be ... | 2001 | 11211221 |
| simultaneous isolation of verotoxin-producing strains of escherichia coli o128:h2 and viruses in gastroenteritis outbreaks. | three outbreaks of gastroenteritis from which the verotoxin producing escherichia coli serotype o128:h2 was isolated are reported. in addition norwalk-like viruses were detected in patients from two of the outbreaks and astrovirus in the third outbreak. while it cannot be specifically determined which of these agents played the major role in these outbreaks, the findings suggest that the viral agents need to be considered in investigations of gastroenteritis outbreaks, regardless of whether bact ... | 2001 | 11247046 |
| prevalence and genomic variation of norwalk-like viruses in central australia in 1995-1997. | norwalk-like viruses (nlvs) have now been found to be important causes of gastroenteritis amongst infants and young children as well as older children and adults. although detected, such viruses appeared not to be a major cause amongst infants and young children hospitalized with gastroenteritis in alice springs, central australia over the period january 1995-december 1997. nine nlv-positive cases were identified amongst stools from 360 different patients. from the nine cases however, eight diff ... | 2000 | 11252671 |
| [virus vaccines]. | 2000 | 11276808 | |
| high level excretion of norwalk-like virus following resolution of clinical illness. | we report the case of an elderly woman excreting high levels (about 5 x 10(5) virions per gram of faeces) of norwalk-like virus (nlv) in the absence of any clinical symptoms of gastroenteritis. analysis by reverse transcription, polymerase chain reaction and dna sequencing was carried out on a 342-nucleotide region of open reading frame 1. this indicated that the nlv belonged to genogroup 2 and was more closely related to the camberwell subgroup, the most common circulating in southeast australi ... | 2001 | 11280609 |
| molecular epidemiology of 'norwalk-like viruses' associated with gastroenteritis outbreaks in new zealand. | outbreaks of gastroenteritis are a major public health problem in new zealand. the introduction of molecular detection methods has now shown that the 'norwalk-like viruses' (nlvs) are the major cause of food and waterborne nonbacterial gastroenteritis. reverse transcription and polymerase chain reaction (rt-pcr) were used to determine the presence of nlvs in faecal specimens from 83 nonbacterial gastroenteritis outbreaks occurring in new zealand between august 1995 and july 1999. further charact ... | 2001 | 11285570 |
| evaluation of the japanese school health surveillance system for influenza. | in order to evaluate the japanese nationwide school absenteeism surveillance system for pediatric influenza in comparison with the national sentinel surveillance for influenza, we used surveillance guidelines (centers for disease control and prevention, 1998) to determine the efficacy of the school health surveillance system (shss). data regarding school absenteeism (age 4-15 years old) was compared with data regarding influenza-like illness (ili) per sentinel sites during the second to the 11th ... | 2001 | 11326126 |
| pathogen filtration, heterogeneity, and the potable reuse of wastewater. | filtration is commonly employed in water and wastewater treatment to remove particles and reduce the concentration of microbial pathogens. all physical models of packed-bed filtration are based on a proportional relationship between particle removal per unit depth of bed and the local particle concentration, dc/dz = -c/l, where l is the filtration length scale. although l is known to vary with time and filter depth for heterogeneous suspensions or "dirty" beds, this paper demonstrates that the f ... | 2001 | 11355195 |
| [studies of acute gastroenteritis among infant and young children in a pediatric clinic]. | from october 1998 to april 1999, 72 stool specimens from patients of acute gastroenteritis were collected in a pediatric clinic in urawa city, japan and were examined for the detection of srsv by electron microscopy and reverse transcription-polymerase chain reaction (rt-pcr). forty-eight (67%) out of 72 were srsv positives by both tests. in this season, a prevalence of srsv peaked in december 1998. among reported clinical symptoms, vomiting was reported more frequently than the other symptoms, ... | 2001 | 11357324 |
| enteric viruses associated with hiv infection in tanzanian children with chronic diarrhea. | to determine whether specific viruses are associated with hiv infection in tanzanian children with chronic diarrhea. | 1994 | 11361370 |
| molecular detection of human calicivirus in young children hospitalized with acute gastroenteritis in melbourne, australia, during 1999. | reverse transcription-pcr and sequence analysis identified calciviruses in 32 of 60 stool specimens (negative for other enteric pathogens) obtained from children admitted to our hospital with acute gastroenteritis. the overall annual incidence rate for calcivirus was 9% (32 of 354 children). molecular analysis identified 30 "norwalk-like virus" genogroup ii (predominantly lordsdale cluster) and 2 "sapporo-like virus" strains. | 2001 | 11427606 |
| an outbreak of viral gastroenteritis in a mother-and-child health clinic. | an outbreak of diarrhoeal disease in a modern mother-and-child health clinic prompted the health authorities to initiate a retrospective cohort study in order to assess the scope of the outbreak and to identify possible risk factors. the management of the clinic had been rather concerned because four similar outbreaks had occurred during the last two years. a total of 151 guests, i.e. mothers with their children, who had arrived some days before the peak of the outbreak for a three-week-stay and ... | 2001 | 11434217 |
| the molecular biology of human caliciviruses. | within the last decade molecular analyses of the genome of norwalk-like viruses (nlvs) have confirmed that this important group of infectious agents belongs to the caliciviridae family. nlvs have a positive-sense, single-stranded rna genome of approximately 7700 nucleotides excluding the polyadenylated tail. the genome encodes three open reading frames: orf 1 is the largest (approximately 1700 amino acids) and is expressed as a polyprotein precursor that is cleaved by the viral 3c-like protease; ... | 2001 | 11444026 |
| structural studies on gastroenteritis viruses. | there are many recent advances in our understanding of the structure-function relationships in rotavirus, a major pathogen of infantile gastroenteritis, and norwalk virus, a causative agent of epidemic gastroenteritis in humans. rotavirus is a large (1000 a) and complex icosahedral assembly formed by three concentric capsid layers that enclose the viral genome of 11 dsrna segments. because of its medical relevance, intriguing structural complexity, and several unique strategies in the morphogene ... | 2001 | 11444031 |
| outbreak of norwalk virus in a caribbean island resort: application of molecular diagnostics to ascertain the vehicle of infection. | in 1998, an outbreak of gastroenteritis affected at least 448 persons including 122 staff at a resort hotel in bermuda. a survey among staff indicated that gastroenteritis was associated with eating or drinking at the hotel (or = 60, 95% ci = 2.4-15.1). multiple specimens of drinking water had elevated faecal coliform levels and escherichia coli present, suggestive of faecal contamination. stools from 18 of the 19 persons with gastroenteritis that were tested were positive for genogroup-ii norwa ... | 2001 | 11467799 |
| nucleotide sequence analysis and development of consensus primers of rt-pcr for detection of norwalk-like viruses prevailing in japan. | a total of 177 different nucleotide sequences of the rna polymerase region of norwalk-like viruses (nlvs) genomes, collected via a nation-wide survey project in japan between 1989 and 1998, were examined by reverse transcription-polymerase chain reaction (rt-pcr) employing various primer pairs. the nucleotide sequences of different strains showed great diversity, with a range of 57 to 100% identities among strains. the strains could be classified into five clusters: norwalk (nv), snow mountain a ... | 2001 | 11468745 |
| clinical spectrum and transmission characteristics of infection with norwalk-like virus: findings from a large community outbreak in sweden. | a large foodborne outbreak caused by norwalk-like virus (nlv) among children and staff at 30 day care centers provided an opportunity to study symptomatology and attack rates among patients in different age groups, as well as secondary transmission rates in centers and households. a retrospective cohort study of 775 subjects from 13 randomly chosen centers was performed. diarrhea was more common in adults than in children (p=.001), whereas the reverse was noted with regard to vomiting (p=.003). ... | 2001 | 11477530 |
| raw oyster consumption and outbreaks of viral gastroenteritis in new zealand: evidence for risk to the public's health. | to investigate the relationship between consumption of raw pacific half shell oysters and outbreaks of norwalk-like virus (nlv) gastroenteritis in auckland in the last third of 1999. | 2001 | 11494991 |
| rapid and efficient extraction method for reverse transcription-pcr detection of hepatitis a and norwalk-like viruses in shellfish. | as part of an effort to develop a broadly applicable test for norwalk-like viruses and hepatitis a virus (hav) in shellfish, a rapid extraction method that is suitable for use with one-step reverse transcription (rt)-pcr-based detection methods was developed. the method involves virus extraction using a ph 9.5 glycine buffer, polyethylene glycol (peg) precipitation, tri-reagent, and purification of viral poly(a) rna by using magnetic poly(dt) beads. this glycine-peg-tri-reagent-poly(dt) method c ... | 2001 | 11526018 |
| molecular detection and sequencing of "norwalk-like viruses" in outbreaks and sporadic cases of gastroenteritis in ireland. | norwalk-like viruses (nlvs) are now established as the most important causative agents of epidemic gastroenteritis worldwide. the overall objective of this study was to determine the molecular epidemiology of irish nlv isolates for the first time by obtaining sequence data from specimens originating from outbreaks and sporadic cases of gastroenteritis. eight samples from sporadic cases of gastroenteritis and nine isolates from separate nlv outbreaks were examined. of the sporadic isolates, six w ... | 2001 | 11536249 |
| sensitive detection and differentiation of sapporo virus, a member of the family caliciviridae, by standard and booster nested polymerase chain reaction. | norwalk virus and sapporo virus (sv) were approved as type species of the genus norwalk-like viruses and the genus sapporo-like viruses, respectively, in the family caliciviridae. nested polymerase chain reaction (pcr), using newly designed primers in the rna-dependent rna polymerase region, was developed to detect and differentiate viruses in the three genetic groups of sv based on the relative size of the pcr products obtained. in addition, a booster nested pcr that performs nested pcr in a si ... | 2001 | 11536253 |
| recombinant norwalk virus-like particles administered intranasally to mice induce systemic and mucosal (fecal and vaginal) immune responses. | recombinant norwalk virus-like particles (rnv vlps) were administered to balb/c mice by the intranasal (i.n.) route to evaluate the induction of mucosal antibody responses. the results were compared to systemic and mucosal responses observed in new and previous studies (j. m. ball, m. e. hardy, r. l. atmar, m. e. connor, and m. k. estes, j. virol. 72:1345-1353, 1998) after oral administration of rnv vlps. immunizations were given in the presence or absence of a mucosal adjuvant, mutant escherich ... | 2001 | 11559804 |
| diffusion of macromolecules and virus-like particles in human cervical mucus. | to determine whether or not large macromolecules and viruses can diffuse through mucus, we observed the motion of proteins, microspheres, and viruses in fresh samples of human cervical mucus using fluorescent recovery after photobleaching and multiple image photography. two capsid virus-like particles, human papilloma virus (55 nm, approximately 20,000 kda) and norwalk virus (38 nm, approximately 10,000 kda), as well as most of the globular proteins tested (15-650 kda) diffused as rapidly in muc ... | 2001 | 11566767 |
| from the centers for disease control and prevention. norwalk-like virus outbreaks at two summer camps--wisconsin, june 2001. | 2001 | 11575312 | |
| outbreaks of acute gastroenteritis associated with norwalk-like viruses in campus settings. | norwalk-like viruses (nlvs) are transmitted by fecally contaminated food, water, fomites, and person-to-person contact. they are a leading cause of acute gastroenteritis epidemics in industrialized countries. nlv outbreaks are characterized by a 12- to 48-hour incubation period; nausea, vomiting, and diarrhea for 24 to 72 hours; and high secondary attack rates. nlv infections spread rapidly on college and university campuses because of close living quarters, shared bathrooms and common rooms, ma ... | 2001 | 11590984 |
| enteric virus contamination of foods through industrial practices: a primer on intervention strategies. | hepatitis a and e viruses, rotaviruses, norwalk-like caliciviruses, and astroviruses are among the enteric viruses known to cause food- and waterborne illness. these viruses are spread by the fecal-oral route and are a major cause of morbidity and mortality worldwide. foods may be contaminated at any time pre- or post-harvest; however, many outbreaks are associated with foods handled by infected restaurant workers. produce may be contaminated by improper irrigation or fertilization practices, by ... | 2001 | 11641770 |
| prevalence of norwalk viruses in southern and northern parts of hiroshima prefecture, japan in 2000/2001 season. | 2001 | 11684786 | |
| characterization of norwalk virus gi specific monoclonal antibodies generated against escherichia coli expressed capsid protein and the reactivity of two broadly reactive monoclonal antibodies generated against gii capsid towards gi recombinant fragments. | norwalk virus causes outbreaks of acute non-bacterial gastroenteritis in humans. the virus capsid is composed of a single 60 kda protein. in a previous study, the capsid protein of recombinant norwalk virus genogroup ii was expressed in an e. coli system and monoclonal antibodies were generated against it. the analysis of the reactivity of those monoclonal antibodies suggested that the n-terminal domain might contain more antigenic epitopes than the c-terminal domain. in the same study, two broa ... | 2001 | 11710959 |
| multistate outbreak of norwalk-like virus gastroenteritis associated with a common caterer. | in february 2000, an outbreak of gastroenteritis occurred among employees of a car dealership in new york. the same meal was also supplied to 52 dealerships nationwide, and 13 states reported illness at dealerships where the banquet was served. a retrospective cohort study was conducted to identify risk factors associated with the illness. stool samples were collected to detect norwalk-like virus, and sera were drawn and tested for immunoglobulin a antibodies to the outbreak strain. by univariat ... | 2001 | 11724717 |
| clinical severity of norwalk virus and sapporo virus gastroenteritis in children in hokkaido, japan. | to clarify the clinical significance and etiologic impact of norwalk virus (nv) and sapporo virus (sv) in viral gastroenteritis in japanese children. | 2001 | 11734762 |
| improved detection of human enteric viruses in foods by rt-pcr. | human enteric viruses (including hepatitis a virus (hav) and norwalk-like viruses (nlvs)) are now recognized as common causes of foodborne disease. while methods to detect these agents in clinical specimens have improved significantly over the last 10 years, applications to food samples have progressed more slowly. in an effort to improve the sensitivity and speed of virus detection from non-shellfish food commodities by reverse transcription-polymerase chain reaction (rt-pcr), we (i) evaluated ... | 2002 | 11742653 |
| genogroup-specific pcr primers for detection of norwalk-like viruses. | norwalk-like viruses (nlv) are a major causative agent of nonbacterial gastroenteritis. there are still many nlv strains that are refractory to gene amplification by ordinary reverse transcription-polymerase chain reaction. this is due mainly to the genetic diversity among nlv, especially mismatches in the primer sequences, which limits this technique in clinical utility. in this study, improved primer sets based on the capsid region, to detect both genogroup i and ii nlv by genogroup-specific m ... | 2002 | 11742657 |
| systemic, mucosal, and heterotypic immune induction in mice inoculated with venezuelan equine encephalitis replicons expressing norwalk virus-like particles. | norwalk-like viruses (nlvs) are a diverse group of single-stranded, nonenveloped, positive-polarity rna viruses and are the leading cause of epidemic acute gastroenteritis in the united states. in this study, the major capsid gene of norwalk virus, the prototype nlv, has been cloned and expressed in mammalian cells using a venezuelan equine encephalitis (vee) replicon expression system. upon infection of baby hamster kidney (bhk) cells with vee replicon particles (vrps), the norwalk virus capsid ... | 2002 | 11752163 |
| norwalk-like virus outbreaks at two summer camps--wisconsin, june 2001. | on june 27 and 28, 2001, the wisconsin division of public health was notified by two local health departments of outbreaks of gastroenteritis at two summer recreational camps (camps a and b) in northern wisconsin. this report summarizes the investigation of these outbreaks, which documents person-to-person transmission of "norwalk-like virus" (nlv) and underscores the importance of cleaning environmental surfaces and the availability and use of hand-washing facilities at recreational camps. | 2001 | 11787574 |
| experimental infection of macaca nemestrina with a toronto norwalk-like virus of epidemic viral gastroenteritis. | norwalk virus (nv) and norwalk-like viruses (nlvs) are common etiologic agents of viral gastroenteritis. viral gastroenteritis is a common disease that is highly transmissible, spreading rapidly through families, institutions, and communities. because methods for in vitro cultivation of norwalk etiologic agents are not available, information regarding this syndrome has come largely from studies in human volunteers. sequential passaging of an nlv through an immunoincompetent newborn pigtail macaq ... | 2002 | 11793394 |
| [hospital outbreak of viral gastroenteritis attributed to norwalk-like viruses in japan]. | norwalk-like viruses (nlvs), rna viruses in the family of caliciviridae, are known as a pathogen of nonbacterial food-borne gastroenteritis associated with eating raw oysters. nlv can spread from person to person with strong infectivity and can cause large epidemics in communities, schools, nursing homes, and hospitals. here, we describe an outbreak of gastroenteritis associated with nlvs, possibly introduced from outside the hospital, in four different wards on four different occasions between ... | 2002 | 11852472 |
| baculovirus expression and antigenic characterization of the capsid proteins of three norwalk-like viruses. | human caliciviruses (hucvs) are antigenically diverse. the antigenic relationships among different hucvs have been difficult to study because hucvs cannot be passaged in the laboratory. in this study, we describe cloning, sequencing and expression of the viral capsid proteins of three hucvs that were identified in outbreaks of acute gastroenteritis in virginia in 1997-1998. yields of the capsid proteins similar to previously expressed recombinant norwalk virus were obtained using the baculovirus ... | 2002 | 11855626 |
| expression and self-assembly of norwalk virus capsid protein from venezuelan equine encephalitis virus replicons. | the norwalk virus (nv) capsid protein was expressed using venezuelan equine encephalitis virus replicon particles (vrp-nv1). vrp-nv1 infection resulted in large numbers of recombinant nv-like particles that were primarily cell associated and were indistinguishable from nv particles produced from baculoviruses. mutations located in the n-terminal and p1 domains of the nv capsid protein ablated capsid self-assembly in mammalian cells. | 2002 | 11861868 |
| development of a virus concentration method and its application to detection of enterovirus and norwalk virus from coastal seawater. | we developed a new procedure for concentration of enteric viruses from water using a negatively charged membrane. rinsing the membrane with 0.5 mm h(2)so(4) (ph 3.0) in order to elute cations prior to viral elution with 1 mm naoh (ph 10.5) promoted poliovirus recovery yields from 33 to 95% when applied to pure water and 38 to 89% when applied to natural seawater from tokyo bay, japan, respectively. this method showed average recovery yields of spiked poliovirus of 62% (n = 8) from 1 liter of art ... | 2002 | 11872447 |
| vectorborne infectious diseases. | 2002 | 11876508 | |
| norwalk virus gastroenteritis among israeli soldiers: lack of evidence for flyborne transmission. | paired sera collected from subjects before and after a fly-control intervention trial conducted in the israel defense force (idf) were tested for seroconversion to norwalk virus (nv) to examine the role of nv as a cause of diarrhea in this population and to ascertain whether flies might also be implicated in transmission. | 2002 | 11876512 |
| structural requirements for the assembly of norwalk virus-like particles. | norwalk virus (nv) is the prototype strain of a group of human caliciviruses responsible for epidemic outbreaks of acute gastroenteritis. while these viruses do not grow in tissue culture cells or animal models, expression of the capsid protein in insect cells results in the self-assembly of recombinant nv virus-like particles (rnv vlps) that are morphologically and antigenically similar to native nv. the x-ray structure of the rnv vlps has revealed that the capsid protein folds into two princip ... | 2002 | 11907243 |
| norwalk-like virus sequences in mineral waters: one-year monitoring of three brands. | in a recent study, rna with nucleotide sequeces specific for "norwalk-like viruses" (nlv) was detected in 11 different brands of european mineral waters. to clarify this finding, a 1-year monitoring study was conducted. samples of three european brands of mineral water without gas were monitored weekly by reverse transcriptase pcr using generic and genogroup-specific oligonucleotides. additional analyses were performed to investigate a possible correlation between nlv sequence contamination and ... | 2002 | 11916714 |
| characterization of norwalk-like virus associated with gastroenteritis in indonesia. | norwalk virus and norwalk-like viruses (nlvs) are reportedly responsible for 2.5-4.0% of nonbacterial acute gastroenteritis (nbag) worldwide. to help clarify the impact of nlvs on nbag in indonesia, stool specimens from 102 patients, 74 with nbag and 28 with bag, were screened for the presence of nlvs, using a reverse transcription-polymerase chain reaction (rt-pcr) assay. the specimens were subtyped using prototype-specific oligonucleotide probes and were sequenced and compared with published n ... | 2002 | 11992587 |
| norwalk virus infection and disease is associated with abo histo-blood group type. | some people are resistant to norwalk virus (nv) infection; however, the factor(s) responsible for resistance or susceptibility to nv infection has not been identified. this study investigated the relationship between a person's abo histo-blood group type and the risk of nv infection and symptomatic disease after clinical challenge. abo phenotypes were identified by using serum samples from volunteers who participated in an nv challenge study (n=51). individuals with an o phenotype were more like ... | 2002 | 12001052 |
| a norwalk-like virus outbreak on the appalachian trail. | in may and june 1999, an outbreak of acute gastrointestinal illness occurred among long-distance hikers on the appalachian trail between catawba and troutville, virginia. an investigation found that 45 out of 70 hikers had become ill within two days of arriving in catawba, virginia. water samples were collected from a general store frequented by the hikers and from several nearby buildings and a popular all-you-can-eat restaurant. symptoms were consistent with those caused by norwalk-like viruse ... | 2002 | 12004584 |
| virus-like particles of a fish nodavirus display a capsid subunit domain organization different from that of insect nodaviruses. | the structure of recombinant virus-like particles of malabaricus grouper nervous necrosis virus (mgnnv), a fish nodavirus isolated from the grouper epinephelus malabaricus, was determined by electron cryomicroscopy (cryoem) and three-dimensional reconstruction at 23-a resolution. the cryoem structure, sequence comparison, and protein fold recognition analysis indicate that the coat protein of mgnnv has two domains resembling those of tomato bushy stunt virus and norwalk virus, rather than the ex ... | 2002 | 12021370 |
| norwalk virus binds to histo-blood group antigens present on gastroduodenal epithelial cells of secretor individuals. | norwalk virus (nv) is a member of the caliciviridae family, which causes acute epidemic gastroenteritis in humans of all ages and its cellular receptors have not yet been characterized. another calicivirus, rabbit hemorrhagic disease virus, attaches to h type 2 histo-blood group oligosaccharide present on rabbit epithelial cells. our aim was to test if, by analogy, recombinant nv-like particles (rnv vlps) use carbohydrates present on human gastroduodenal epithelial cells as ligands. | 2002 | 12055602 |
| [norwalk virus: recent findings]. | acute gastroenteritis due to norwalk virus(nv), a member of the family caliciviridae, is a common illness worldwide. nv is a human pathogen causing food-borne and water-borne diseases that occur in various epidemiological settings. the disease is mild and self-limiting and the symptomatic phase lasts 24 to 72 hours. genetic analyses of the polymerase and the capsid protein indicate that nv is grouped into two clusters, genogroup i and genogroup ii. the development of recombinant virus-like parti ... | 2002 | 12078086 |
| [molecular epidemiology of norwalk virus]. | norwalk virus is one of the most important diarrheal viruses. although the virus was discovered in 1970, the genetic analysis has started from 1990. the virus appears in sporadic cases but also in outbreaks in children and adults. the symptoms are vomiting and diarrhea, but rarely are convulsion and others. the molecular epidemiological method is useful to detect the pathogen in environments and hosts. as the results of molecular epidemiology, it was found that the common virus with the identica ... | 2002 | 12078087 |
| [epidemiology on norwalk virus-related gastroenteritis outbreaks among elderly persons living in nursing homes]. | person-to-person transmission of norwalk virus(nv) is important factor for outbreaks in nursing homes in addition to foodborne and waterbone transmission. nv spread easily among residents and staffs through the care process and highly infectious contamination generated by vomitus and feces remains on the environmental surface. as a result, the outbreak continues for long period(a few weeks) compared with foodborne gastroenteritis outbreak in restaurant. for prevention and control of nv outbreak ... | 2002 | 12078088 |
| [identification and genotyping of norwalk virus by stringent microplate hybridization of pcr products]. | there are many genotypes of norwalk virus(nv), and the microplate hybridization method for identification and genotyping of nv requires preparation of many probes. however, the method is simple and the detection sensitivity is high at 10 ng/ml dna, and many samples can be simultaneously examined in an identification test and genotyping of nv. increasing the hybridization temperature increases precision and the homology rate between a probe and dna fragment can be estimated. mixed genotypes of nv ... | 2002 | 12078091 |
| [rapid and efficient detection method of norwalk virus]. | a rapid and efficient rt-pcr with fluorogenic probe(taqman-pcr) was developed for detection of norwalk virus(nv) genomes in clinical specimens. we designed nv genogroup specific primers and fluorogenic probes in the junction of open reading frame (orf)1 and orf2. eighty specimens from patients of gastroenteritis, in which nv-like particles were detected by electron microscopy, were examined by taqman-pcr and rt-pcr using primer sets previously reported; two sets in rdrp region of nv and one set ... | 2002 | 12078092 |
| [characteristic of norwalk gastroenteritis and its prevention]. | the application of recently developed molecular technique revealed the important role of the norwalk virus(nv). the major role of the nv as agents of food and water-related outbreaks of gastroenteritis has now been recognized in the world. moreover, a part of nv is also documented as important agents of gastroenteritis in childhood and infancy. a high rate of food-related viral gastroenteritis outbreaks was observed following ingestion of shellfish in japan. specific methods are not available fo ... | 2002 | 12078095 |
| [the relationship between epidemic gastroenteritis caused by norwalk viruses (nvs) and acute gastroenteritis in children--based on the history of nvs in japan]. | norwalk viruses(nvs) are well known pathogens that can cause acute nonbacterial epidemic gastroenteritis in adults as well as acute gastroenteritis in children. in food poisoning cases due to raw oysters, nvs is considered as an important pathogen and the molecular epidemiological studies of nvs are the most suitable method to trace these routes of infections in conjunction with oyster supply mechanism. furthermore, the prevalence of genotypes of nvs which are detected from cases of acute gastro ... | 2002 | 12078096 |
| [contamination of oyster sea farm with the norwalk virus: mechanisms and control]. | the norwalk virus(nv) is widely known as a cause of nonbacterial food poisoning, infant diarrhea, and acute gastroenteritis in the winter months between november and march. while it is strongly suspected that nv that is excreted by humans flows into coastal seawaters via rivers and wastewater treatment facilities to contaminate oysters that are grown in farms in the area, light has yet to be shed on the behavior of this virus in the natural environment. we therefore conducted a polymerase chain ... | 2002 | 12078097 |
| [vaccine development for norwalk virus]. | the rationale for developing a vaccine generally is made on the basis of the clinical and socioeconomical significance of a specific viral disease. the disease burden for rotavirus gastroenteritis in infants is well evaluated and several candidate vaccines for rotavirus has now been developing. an increasing recognition of the clinical significance of norwalk virus causing acute gastroenteritis in humans of all ages, foodborne outbreaks in adults, and relatively severe gastroenteritis in childre ... | 2002 | 12078098 |
| cross-reactivity among several recombinant calicivirus virus-like particles (vlps) with monoclonal antibodies obtained from mice immunized orally with one type of vlp. | human caliciviruses (hucvs) are classified into the norwalk-like viruses (nlv) and sapporo-like viruses (slv) as genera within the family caliciviridae: the nlv genus is further classified into genogroups i and ii, based on sequence similarities. to study the antigenic determinants on the hucv capsid protein and develop new diagnostic tools for field samples, we established and characterized monoclonal antibodies (mabs) against baculovirus-expressed recombinant hucv virus-like particles (vlps). ... | 2002 | 12089262 |
| concentration and detection of caliciviruses from food contact surfaces. | outbreaks of human norwalk virus (nv) and norwalk-like viruses often originate in food service establishments. no reliable method is available for the detection of these human caliciviruses on food contact surfaces. we describe a simple method for the detection of nv from stainless steel work surfaces using cultivable feline calicivirus (fcv) as a model. stainless steel surfaces were artificially contaminated with known amounts of fcv, followed by its elution in a buffer solution. three methods ... | 2002 | 12092735 |
| viral causes of diarrhea. | 2002 | 12093939 | |
| viruses detected in the caecum contents of healthy pigs representing a new genetic cluster in genogroup ii of the genus "norwalk-like viruses". | viruses of the genus 'norwalk-like viruses' (nlvs) detected in humans have been genetically classified into two major genetic groups, genogroups i and ii (gi and gii), which together are made up of at least 14 genetic subgroups. however, a comparable classification of nlvs in other species remains to be carried out. we sequenced a 2-kb region from within the rna polymerase gene to the 3' end of open reading frame 2 (orf2) of two nlv strains previously detected in the caecum contents of healthy p ... | 2002 | 12191780 |
| detection and differentiation of norwalk virus by reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay. | we have developed a reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay (rt-pcr-elisa), using genetic cluster-specific probes in a microtiter plate format, for the detection and differentiation of norwalk virus (nv) in stool samples. the specificity of the rt-pcr-elisa was confirmed by testing 76 stool specimens and 15 tissue culture fluids derived from growths of unrelated viruses. the sensitivity of the rt-pcr-elisa was compared with conventional pcr and south ... | 2002 | 12210421 |
| substrate specificity of the norwalk virus 3c-like proteinase. | the norwalk virus (nv) is the prototype strain of human caliciviruses that cause epidemic outbreaks of foodborne and waterborne gastroenteritis. these viruses do not grow in cell culture and the mechanisms of virus replication are obscure. the nv genome is a 7.7 kb ssrna molecule that encodes three open reading frames (orfs). the first orf is a 1789 amino acid polyprotein that is processed into nonstructural proteins by a viral protease similar to the picornavirus 3c protease. primary cleavage s ... | 2002 | 12367748 |
| inactivation of hepatitis a virus and a calicivirus by high hydrostatic pressure. | potential application of high hydrostatic pressure processing (hpp) as a method for virus inactivation was evaluated. a 7-log10 pfu/ml hepatitis a virus (hav) stock, in tissue culture medium, was reduced to nondetectable levels after exposure to more than 450 mpa of pressure for 5 min. titers of hav were reduced in a time- and pressure-dependent manner between 300 and 450 mpa. in contrast, poliovirus titer was unaffected by a 5-min treatment at 600 mpa. dilution of hav in seawater increased the ... | 2002 | 12380746 |
| zirconium hydroxide effectively immobilizes and concentrates human enteric viruses. | detection of human enteric viruses in foods and environmental samples requires concentration of viruses from complex matrices before application of molecular or cultural methods. previous studies have described the use of zirconium hydroxide to concentrate bacteria from clinical, environmental, and food samples. | 2002 | 12390492 |
| an outbreak of viral gastroenteritis following environmental contamination at a concert hall. | in january 1999, an outbreak of viral gastroenteritis affected more than 300 people who attended a metropolitan concert hall over a 5-day period. norwalk-like virus (nlv) was confirmed in faecal samples by reverse transcription polymerase chain reaction assay. the index case was a concert attendee who vomited in the auditorium and adjacent male toilet. gastrointestinal illness occurred among members of 8/15 school parties who attended the following day. children who sat on the same level of the ... | 2002 | 12403111 |
| ultraviolet inactivation of feline calicivirus, human enteric viruses and coliphages. | norwalk and norwalk-like viruses (nlv) are major causes of food- and water-related disease in the united states. there is no host cell line in which the nlv can be tested for infectivity. feline calicivirus (fcv) and nlv both belong to the family caliciviridae. fcv can be assayed for infectivity in the crandell reese feline kidney cell line, so fcv serves as a surrogate for nlv. this study is the first report of uv inactivation of fcv and also of using the plaque technique, in contrast to the 50 ... | 2002 | 12405148 |
| binding of norwalk virus-like particles to abh histo-blood group antigens is blocked by antisera from infected human volunteers or experimentally vaccinated mice. | attachment of norwalk (nv), snow mountain (smv), and hawaii (hv) virus-like particles (vlps) to specific abh histo-blood group antigens was investigated by using human saliva and synthetic biotinylated carbohydrates. the three distinct norwalk-like viruses (nlvs) have various capacities for binding abh histo-blood group antigens, suggesting that different mechanisms for nlv attachment likely exist. importantly, antisera from nv-infected human volunteers, as well as from mice inoculated with pack ... | 2002 | 12414974 |
| distribution of human virus contamination in shellfish from different growing areas in greece, spain, sweden, and the united kingdom. | viral pollution in shellfish has been analyzed simultaneously across a wide range of geographical regions, with emphasis on the concomitant variations in physicochemical characteristics and social features. the methods for sample treatment and for the detection of human enteric viruses were optimized by the participating laboratories. the second part of this study involves the selection of a protocol for virus detection, which was validated by analyzing the distribution and concentration of huma ... | 2002 | 12450820 |
| norwalk virus-like particle hemagglutination by binding to h histo-blood group antigens. | noroviruses are a major cause of epidemic acute nonbacterial gastroenteritis worldwide. here we report our discovery that recombinant norwalk virus virus-like particles (rnv vlps) agglutinate red blood cells (rbcs). since histo-blood group antigens are expressed on gut mucosa as well as rbcs, we used rnv vlp hemagglutination (ha) as a model system for studying nv attachment to cells in order to help identify a potential nv receptor(s). rnv vlp ha is dependent on low temperature (4 degrees c) and ... | 2003 | 12477845 |