Publications

efficacy of a recombinant norwalk virus protein enzyme immunoassay for the diagnosis of infections with norwalk virus and other human "candidate" caliciviruses.	a recombinant norwalk virus antigen enzyme immunoassay (rnv eia) for the detection fo norwalk virus (nv) antibodies was evaluated using sera from volunteers and patients infected with norwalk, hawaii, snow mountain agent, small round structured viruses (srsv), and human calicivirus (hucv) strains. the results for nv antibodies correlated well with previous results obtained using a nv radioimmunoassay. the test rnv eia was found to be highly specific for nv. the results of tests on sera obtained ...	1993	8263497
detection of enteric viruses in oysters by using the polymerase chain reaction.	a procedure for the detection of enteric viral nucleic acid in oysters by the polymerase chain reaction was developed. known quantities of poliovirus type 1 were seeded into oysters. virus was extracted and concentrated by using organic flocculation and polyethylene glycol precipitation. inhibitors of reverse transcription-polymerase chain reaction were present in the oyster extracts, preventing amplification of target viral nucleic acid. the use of cetyltrimethylammonium bromide precipitation s ...	1993	8382024
etiology of acute diarrhea among united states military personnel deployed to south america and west africa.	a study of acute diarrhea was conducted from 1985 to 1987 among u.s. military personnel participating in routine shipboard exercises in south america and west africa and ground troops deployed to coastal ecuador. an enteropathogen was identified in 146 (51%) of 289 acute cases of diarrhea. enterotoxigenic escherichia coli, found in 50 (17%) patients with diarrhea, was the most commonly identified enteropathogen. viral enteropathogens were also found in a high percentage of acute cases of diarrhe ...	1993	8383470
[rotavirus, adenovirus, astrovirus, calicivirus and small round virus particles in feces of children with and without acute diarrhea, from 1987 to 1988, in the greater são paulo].	between 1987 and 1988, 193 faecal specimens from children, with or without diarrhea, were submitted to enzyme immunoassay, polyacrylamide-gel electrophoresis and electronmicroscopy tests for virus detection. the positivity for rotavirus, adenovirus, astrovirus, calicivirus and small round virus particles (srvp) was 11.3%, 3.1%, 2.1%, 1.0% and 4.1%, respectively, for the 97 children with acute diarrhea. of the 96 children without diarrhea, 4.2% were positive for rotavirus, 1.0% for calicivirus an ...	1993	8278758
viral gastroenteritis.		1993	8380619
sequence and genome organization of a human small round-structured (norwalk-like) virus.	small round-structured viruses (srsvs), also known as norwalk or norwalk-like viruses, are the major worldwide cause of acute, epidemic nonbacterial gastroenteritis in humans. these viruses, which contain a single-stranded rna genome, have remained refractory to molecular characterization because of the small amounts of virus in clinical samples and the absence of an animal model and an in vitro culture system. the complete genomic nucleotide sequence of an srsv, southampton virus, was determine ...	1993	8380940
norwalk virus infection among desert storm troops.		1993	8383727
prevalence of antibodies to norwalk virus in england: detection by enzyme-linked immunosorbent assay using baculovirus-expressed norwalk virus capsid antigen.	a total of 3,250 serum specimens collected in england in 1991 and 1992 were tested by an indirect enzyme-linked immunosorbent assay for antibody to norwalk virus using baculovirus-expressed capsid antigen, and 2,382 (73.3%) were positive. the prevalence of norwalk virus antibody differed regionally. it was lowest (24.6%) in 6- to 11-month-old infants and increased to 89.7% in persons over 60 years old.	1993	8385148
recognizing, preventing viral gastroenteritis.		1993	8390042
subclass-specific serum antibody responses to recombinant norwalk virus capsid antigen (rnv) in adults infected with norwalk, snow mountain, or hawaii virus.	subclass-specific antibody responses to the norwalk virus capsid protein in adults challenged with norwalk, snow mountain, or hawaii virus were evaluated by solid-phase enzyme immunoassay using recombinant norwalk virus capsid antigen (rnv). fourfold or greater serum immunoglobulin g (igg) antibody responses to rnv were detected in 15 of 20 volunteers challenged with norwalk virus, and serum iga and igm antibody responses to rnv were seen in almost all subjects who had rnv igg responses. serum r ...	1993	8391025
outbreaks of food-borne and waterborne viral gastroenteritis.	norwalk virus infection is the epidemiologic prototype for outbreaks of food-borne and waterborne gastroenteritis. around the world, norwalk virus and norwalk-like viruses appear to be major causes of food-borne and waterborne illness. assessment of the overall significance of viral agents to the epidemiology of food-borne and waterborne illness is hampered by the lack of surveillance throughout much of the world. in areas where food-borne and waterborne illness surveillance is conducted, outbre ...	1993	8395330
sequence and genomic organization of norwalk virus.	a library of overlapping cdnas obtained from norwalk virus purified from stools of human volunteers (jiang et al., 1990, science 250, 1580-1583) was used to obtain the nucleotide sequence of the viral genome. the sequence has a total of 7642 nucleotides, excluding the 3' poly(a) tail, and has a base composition of 48% g + c. three open reading frames (orf) are predicted in the sequence. the longest orf (orf1, nucleotides (nt) 146 to 5359) is predicted to encode a polyprotein precursor to nonstru ...	1993	8391187
outbreak of srsv gastroenteritis at an international conference traced to food handled by a post-symptomatic caterer.	in an outbreak of small round structured virus (srsv) gastroenteritis at an international aids conference 67 people were ill with diarrhoea or vomiting, one requiring admission to hospital. epidemiological investigations demonstrated that the vehicle of infection was food prepared by a foodhandler who was recovering from a mild gastrointestinal illness. the food most strongly associated with illness, coronation chicken, was prepared by the food handler on the second day after symptoms ceased. th ...	1993	8394241
an outbreak of norwalk-like gastroenteritis associated with contaminated drinking water at a caravan park.	during the 1989 christmas holiday period, a large outbreak of gastroenteritis occurred among persons staying at a caravan park in southern new south wales. review of local hospital records found that 77 per cent of patients presenting with infective diarrhoea between 29 december and 3 january had stayed at the caravan park. in a retrospective cohort study we compared rates of illness among caravan park patrons exposed to different water sources. stools were tested for pathogens and convalescent ...	1993	8395224
comparison of the reactivities of baculovirus-expressed recombinant norwalk virus capsid antigen with those of the native norwalk virus antigen in serologic assays and some epidemiologic observations.	since the discovery of the norwalk virus (nv) by immune electron microscopy (iem) in 1972, serologic studies with this virus have relied on particle-positive fecal material from infected volunteers as the source of antigen because it has not been possible to propagate this virus in cell culture. however, the recent cloning of the nv (strain 8fiia) genome and expression of the capsid protein in a baculovirus system to form "virus-like particles" has provided a consistent source of antigen (design ...	1993	8396590
detection of norwalk virus in the uk by the polymerase chain reaction.	we have developed a polymerase chain reaction for the detection of norwalk virus using the published sequence of the virus rna dependent rna polymerase gene and have used this to clone and sequence this region of a virus from a uk outbreak. we have applied this method to a panel of uk norwalk-like viruses using both tet-z and taq dna polymerases and found that amplification produces a multiplicity of bands from stool samples. however, in combination with southern blotting, taq polymerase amplifi ...	1993	8405951
small round virus excretion in long-stay geriatric patients.	the role of small round viruses (srvs) in gastroenteritis has not been evaluated. we undertook a study to evaluate srv excretion in 40 elderly patients over 12 months in long-stay, geriatric wards. the 40 patients (11 male, 29 female) had an age range of 73-99 years. samples were received monthly as long as the patients were alive. samples were available from 30 patients (75%) for 6 months or more, and 20 (50%) patients completed the study. ten grams of faeces were collected and prepared as 10-2 ...	1993	8263506
[viral gastroenteritis].		1993	8260517
from the centers for disease control and prevention. multistate outbreak of viral gastroenteritis related to consumption of oysters--1993.		1994	8277537
incidence of norwalk virus infections during a prospective epidemiological study of drinking water-related gastrointestinal illness.	to determine the seroprevalence of norwalk virus and whether norwalk virus contributed to an observed increase in illness in tap water drinkers participating in a prospective epidemiological study, sera collected during the study were examined for changes in norwalk virus antibody titer, using a specific enzyme immunoassay. antibodies to norwalk virus were measured in sera collected in march, june and september 1988 and in june 1989, and antibodies were found in 79% of the individuals. seropreva ...	1994	8000960
norwalk virus infection of volunteers: new insights based on improved assays.	norwalk virus infection is a common cause of gastroenteritis in humans. the clinical features and virologic and immunologic responses following oral administration of norwalk virus to 50 volunteers were monitored. new elisas using recombinant virus particles as the antigen source were used to assess the pattern of virus shedding and the specific immune responses. forty-one subjects (82%) became infected; 68% were symptomatic and 32% were asymptomatic. the proportion of subjects infected was simi ...	1994	8014518
measurement of iga responses following norwalk virus infection and other human caliciviruses using a recombinant norwalk virus protein eia.	an enzyme immunoassay employing recombinant norwalk virus capsid protein was evaluated for the measurement of iga responses. tests on 23 volunteers and patients known to have been infected with norwalk virus (nv) showed that 19 developed significant iga responses, 2 had unchanging levels of iga and 2 failed to respond. there was no evidence of iga responses to nv following infection with hawaii or snow mountain-like viruses. tests on sera from patients involved in outbreaks associated with eatin ...	1994	8062871
molecular characterization of hawaii virus and other norwalk-like viruses: evidence for genetic polymorphism among human caliciviruses.	hawaii virus (hv), from a 1971 family outbreak of gastroenteritis, is serotypically distinct from norwalk virus (nv), recently identified as a human calicivirus by molecular analysis. about 2600 consecutive nucleotides of the hv genome (including those encoding the viral capsid protein) and part of the polymerase region of three other viruses (mdv1, mdv6 and sv7) were sequenced. comparison of the amino acid sequence of the capsid protein of hv with nv and other human caliciviruses (toronto virus ...	1994	8077710
3'-terminal sequence of a small round structured virus (srsv) in japan.	we determined the nucleotide sequence of about 1,000 bases from the 3'-terminus of a small round structured virus (srsv), which caused a gastroenteritis outbreak in chiba prefecture, japan, in 1987. the sequence was compared with the corresponding sequence region of norwalk virus; it consisted of a part of the open reading frame 2 (orf2), whole orf3, and 3'-noncoding region (ncr). the 624-base-long orf3 had sequence homology of 68% with the corresponding region of norwalk virus. (the amino acid ...	1994	8198445
epidemiological study of norwalk virus infections in japan and southeast asia by enzyme-linked immunosorbent assays with norwalk virus capsid protein produced by the baculovirus expression system.	in this study, we investigated norwalk virus (nv) antigen and antibody to recombinant nv (rnv) in human populations in japan and southeast asia by enzyme-linked immunosorbent assays (elisas). baculovirus-expressed recombinant nv (rnv) capsid protein was used for preparing antisera to rnv or used as an antigen for detecting antibody to rnv. the elisas were specific for nv and had sensitivities equivalent to or higher than those of the previously developed radioimmunoassays. in 159 stool samples o ...	1994	8126165
molecular characterization and expression of the capsid protein of a norwalk-like virus recovered from a desert shield troop with gastroenteritis.	norwalk virus (nv) infection was recently found to be associated with gastroenteritis in u.s. military troops stationed in saudi arabia during the 1990 desert shield operation. we identified a norwalk-like virus in the stools of two military personnel with gastroenteritis by elisa and iem. by rt-pcr and sequence analysis, the nucleotide sequence of part of the polymerase region of each of these two "desert shield" strains (dsv275 and dsv395) was found to be 73% identical to the corresponding reg ...	1994	8128635
seroprevalence studies using a recombinant norwalk virus protein enzyme immunoassay.	a recombinant norwalk virus (nv) protein enzyme immunoassay was used to study the age of acquisition of nv igg in various populations. in london, england, there was little evidence of infection during the first 2 years of life. however, the prevalence of nv igg rose steadily throughout the period that children attend school, reaching a peak of 70% in the group aged 11-16 years. high levels of maternal antibody were detected in infants aged < 3 months. comparison of the acquisition of antibodies ...	1994	8158109
prevalence of antibodies to norwalk virus among amerindians in isolated amazonian communities.	the seroepidemiology of norwalk virus infections was examined among amerindians belonging to eight relatively isolated communities in the amazon region by means of a new enzyme immunoassay using recombinant norwalk virus antigen. the seroprevalence of antibodies to norwalk virus ranged from 39% in the maiogong to 100% in the kubenkrankrein. the distribution of antibody levels varied greatly among groups; five of the eight communities had an antibody prevalence greater than 90% with many high val ...	1994	8166133
application of pcr to detect norwalk virus in fecal specimens from outbreaks of gastroenteritis.	norwalk virus (nv) and other small round-structured viruses (srsvs) are frequent causes of gastroenteritis outbreaks. the recent cloning and sequencing of the nv genome has made it possible to detect nv and norwalk-related viruses from fecal specimens by reverse transcription (rt)-pcr. we applied this technique to the examination of a total of 139 fecal specimens from 19 outbreaks characterized by nv serology, including 56 samples from 7 nv outbreaks, 36 from 6 norwalk-related virus outbreaks, a ...	1994	8195372
norwalk virus-associated gastroenteritis traced to ice consumption aboard a cruise ship in hawaii: comparison and application of molecular method-based assays.	investigation of an outbreak of acute nonbacterial gastroenteritis on a cruise ship provided an opportunity to assess new molecular method-based diagnostic methods for norwalk virus (nv) and the antibody response to nv infection. the outbreak began within 36 h of embarkation and affected 30% of 672 passengers and crew. no single meal, seating, or food item was implicated in the transmission of nv, but a passenger's risk of illness was associated with the amount of ice (but not water) consumed (c ...	1994	8150941
detection of norwalk virus or norwalk-like virus infections in finnish infants and young children.	norwalk virus (nv) and norwalk-like viruses are important causes of epidemic nonbacterial gastroenteritis in older children and adults. serologic responses to nv of 154 finnish infants and young children participating in a rotavirus vaccine study were examined by elisa with a recently available baculovirus-expressed recombinant nv capsid protein. in 4 serially collected sera (at the median ages of 3, 4, 14, and 23 months), 49% of children had at least one nv infection over the approximately 2-ye ...	1994	8195618
viral gastroenteritis associated with consumption of raw oysters--florida, 1993.	during november 20-30, 1993, four county public health units (cphus) of the florida department of health and rehabilitative services (hrs) in northwestern florida conducted preliminary investigations of seven separate outbreaks of foodborne illness following consumption of raw oysters. on december 1, the hrs state health office initiated an investigation to characterize the illness, examine risk factors for oyster-associated gastroenteritis, and quantify the dose-response relation. this report p ...	1994	8202078
detection of immunoglobulin m (igm), iga, and igg norwalk virus-specific antibodies by indirect enzyme-linked immunosorbent assay with baculovirus-expressed norwalk virus capsid antigen in adult volunteers challenged with norwalk virus.	pre- and postexposure sera collected from 17 adult volunteers challenged with norwalk virus as described previously (d. y. graham, x. jiang, t. tanaka, a. opekun, p. madore, and m. k. estes, j. infect. dis. 170:34-43, 1994) were examined for norwalk virus-specific immunoglobulin m (igm), iga, and igg by indirect enzyme-linked immunosorbent assays with recombinant norwalk virus antigen bound to the solid phase. sixteen of the 17 volunteers had evidence of past infection, all presenting with preex ...	1994	7883902
human enteric caliciviruses are genetically distinct from small round structured viruses.		1994	7906820
small round structured viruses: airborne transmission and hospital control.		1994	7910270
transmission of a small round structured virus by vomiting during a hospital outbreak of gastroenteritis.	an outbreak of gastroenteritis due to a small round structured virus (srsv) (norwalk-like virus) occurred in an elderly care unit, affecting a total of 126 patients and staff. the outbreak caused major disruption to the provision of health care services by the unit over a 3-week period. following the outbreak a study was undertaken to explore risk factors for acquisition of srsv infection by health care workers on the unit. exposure to patients nearby who were vomiting and the number of close co ...	1994	7915285
a hospital outbreak due to norwalk virus.	an outbreak of diarrhoea and vomiting began at a hospital for the elderly on the 25 october 1991. the symptoms and pattern of spread suggested a viral aetiology from a point source. electron microscopy confirmed the presence of norwalk virus. the first wave of illness affected 37 patients and 28 staff. secondary cases occurred on all wards. analytical studies of food consumed at three lunchtime meetings by staff and visitors to the hospital demonstrated a clear association between eating sandwic ...	1994	7915286
human enteric caliciviridae: a new prevalent small round-structured virus group defined by rna-dependent rna polymerase and capsid diversity.	sequence comparison of the rna-dependent rna polymerases of small round-structured viruses (srsvs) from 10 recent u.k. outbreaks of gastroenteritis revealed significant genetic variation. computer analyses indicated that these viruses can be divided into two discrete groups. srsv group i contains the previously characterized antigenic type 1 norwalk and type 3 southampton viruses. the amino acid sequences of the rna polymerase, capsid and orf3 of these two viruses are relatively similar (about 9 ...	1994	8046390
small round viruses and gastroenteritis.		1994	7915389
developmental control of ifn-alpha expression in murine embryos.	the expression of ifn-alpha transcripts was investigated in murine embryos, fetuses, and fetal annexes in mid and late pregnancy. we have shown by northern blot analysis, reverse transcription-polymerase chain reaction, and in situ hybridization the presence of ifn-alpha transcripts in mouse placenta, fetus, and newborn. from the 14th day of gestation until birth, a typical ifn-alpha transcript (1.2 kb) is found in the fetus. a transcript of larger size (2.2 kb) appears near birth and is present ...	1994	7925651
etiology and outcome of diarrhea after marrow transplantation: a prospective study.	acute diarrhea after marrow transplant is usually ascribed to acute graft-vs.-host disease (gvhd) or infection, with a reported 40%-50% incidence of infection. the aim of this study was to determine the incidence of acute diarrhea after transplantation, its causes, and its outcome.	1994	7926504
sequence similarity of human caliciviruses and small round structured viruses.	the application of reverse transcription-polymerase chain reaction (rt-pcr) using primers directed to the rna dependent rna polymerase region within orf1 of norwalk virus (nv) showed that 31 percent of morphologically typical human caliciviruses (hucv) and 57% of small round structured viruses (srsvs) produced a product of 470 bp similar to the nv control, nv 8fiia/68/us. alignment of the amino acid sequences of morphologically typical hucvs with previously published sequences for srsvs, nv, and ...	1994	7931187
identification of norwalk virus in artificially seeded shellfish and selected foods.	a rotavirus dsrna purification protocol was adapted to extract norwalk ssrna from artificially contaminated shellfish, and a sensitive reverse transcription-polymerase chain reaction assay for norwalk virus was devised to identify an estimated 20-200 genomic copies. the technique includes deproteinization with guanidinium isothiocyanate, adsorption of rna to hydroxyapatite, and sequential precipitation with cetyltrimethylammonium bromide and ethanol. the protocol allows high recovery of viral rn ...	1994	7989435
the role of the pre-symptomatic food handler in a common source outbreak of food-borne srsv gastroenteritis in a group of hospitals.	a common source outbreak of small round structure virus (srsv) gastroenteritis affected 81 patients and 114 staff in four hospitals served by one central hospital kitchen. eating salad items was found to be significantly associated with illness. in a cohort study of a staff buffet function eating turkey salad sandwiches was associated with illness (relative risk = 2.4; 95% ci = 1.4-4.1; p = 0.003), and a case control study of patients in one hospital showed an odds ratio of 6.6 (95% ci = 1.0-71. ...	1994	7995361
from the centers for disease control and prevention. viral gastroenteritis associated with consumption of raw oysters--florida, 1993.		1994	8046794
sequence diversity of small, round-structured viruses in the norwalk virus group.	we have determined the nucleotide sequences of a highly conserved region of the rna-dependent rna polymerase of the prototype snow mountain agent (sma) and of four other small, round-structured viruses (antigenically norwalk virus [nv]-like or sma-like) following reverse transcription-pcr amplification of viral rna obtained from human stools. the stool samples were either from volunteers administered sma or from sporadic cases and outbreaks of gastroenteritis that occurred in japan and the unite ...	1994	8057474
three-dimensional structure of baculovirus-expressed norwalk virus capsids.	the three-dimensional structure of the baculovirus-expressed norwalk virus capsid has been determined to a resolution of 2.2 nm using electron cryomicroscopy and computer image processing techniques. the empty capsid, 38.0 nm in diameter, exhibits t = 3 icosahedral symmetry and is composed of 90 dimers of the capsid protein. the striking features of the capsid structure are arch-like capsomeres, at the local and strict 2-fold axes, formed by dimers of the capsid protein and large hollows at the ...	1994	8035511
rotavirus and other viral causes of gastroenteritis.	diarrheal diseases are a major cause of childhood morbidity and mortality worldwide. viruses are the leading cause of diarrhea, and rotavirus is the major cause of severe dehydrating diarrhea in both developed and developing countries. children with viral gastroenteritis generally present with watery non-bloody diarrhea, often with vomiting and low grade fever. disease is self-limited and treatment is simple--fluid and electrolyte replacement, preferably via the oral route, with early refeeding. ...	1994	7838602
recent developments with human caliciviruses.	caliciviruses (cvs) are human and animal pathogens. the best known human cvs are norwalk virus (nv) and snow mountain agent. recent molecular studies have confirmed that cvs are a unique taxonomic family. these molecular studies also have clarified relationships among previously poorly characterized human enteric viruses, led to new diagnostic tests and identified potential relationships between human and animal cvs. the purpose of this review was to describe these recent developments.	1994	7845754
characterization of a variant strain of norwalk virus from a food-borne outbreak of gastroenteritis on a cruise ship in hawaii.	a gastroenteritis outbreak affecting at least 217 (41%) of 527 passengers on a cruise ship was caused by a variant strain of norwalk virus (nv) that is related to but distinct from the prototype nv strain. consumption of fresh-cut fruit served at two buffets was significantly associated with illness (p < or = 0.01), and a significant dose-response relationship was evident between illness and the number of various fresh-cut fruit items eaten. seven (58%) of 12 paired serum specimens from ill pers ...	1994	8027335
genomic diversity of small round structured viruses in the united kingdom.	fifty-two faecal specimens collected in the united kingdom between 1986 and 1992, which contained small round structured virus (srsv) particles, were tested by reverse transcriptase polymerase chain reaction assays using two primer pairs derived from sequences of snow mountain agent and norwalk virus. there was poor correlation between results obtained with each primer pair. twenty specimens (38%) gave positive bands with sm51/31 primers and 18 (34%) were positive with sm52/32 primers, with a to ...	1994	7852972
enteropathogens associated with acute diarrhoeal diseases.	five types of escherichia coli are responsible for as much as 25% of all diarrheal diseases in developing countries. they tend to be transmitted via contaminated foods, particularly weaning foods, and water. they include enterotoxigenic, enteropathogenic, enteroadherent, enteroinvasive, and enterohemorrhagic e. coli. shigella species are responsible for 10-15% of acute diarrheas in children less than 5 years old and the most common etiologic agents of childhood dysentery. shigellosis is common i ...	1994	7835992
viral gastroenteritis associated with a sandwich bar.		1994	7522804
comparison of the polymerase region of small round structured virus strains previously classified in three antigenic types by solid-phase immune electron microscopy.	we have used a reverse transcription-polymerase chain reaction with nested sets of primers to determine the nucleotide sequences of a 166 base pair segment of the rna polymerase region of seven strains of small round structured viruses (srsvs) from the united kingdom. these srsv strains were previously classified by solid-phase immune electron microscopy into three antigenic types--uk2, uk3 and uk4, which are comparable to the prototype strains norwalk virus, hawaii agent, and snow mountain agen ...	1994	7515226
airborne transmission of a small round structured virus.		1994	7904013
airborne transmission of a small round structured virus.		1994	7906368
airborne transmission of a small round structured virus.		1994	7906369
role of small round viruses and small round structured viruses.		1994	7912361
role of small round viruses and small round structured viruses.		1994	7912362
gastroenteritis associated with oysters.		1994	7514927
development of a method for detection of enteroviruses in shellfish by pcr with poliovirus as a model.	the application of the pcr to complex samples is hindered by amplification inhibitors. we describe a reverse transcription-pcr-based method capable of inhibitor removal for the detection of enteroviruses in shellfish. initial virus extraction stages based on a modified polyethylene glycol precipitation technique (g.d. lewis and t.g. metcalf, appl. environ. microbiol. 54:1983-1988, 1988) were followed by virus purification with 1,1,2-trichloro,2,2,1-trifluoroethane and concentration by ultrafiltr ...	1994	7521997
emerging pathogens.		1994	10138458
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
identification of minireovirus as a norwalk-like virus in pediatric patients with gastroenteritis.	in 1977, 30- to 32-nm virus-like particles, named minireovirus because of their unique morphologic appearance, were detected by electron microscopy in the stools of infants and young children with gastroenteritis. sequence analysis of approximately 2,800 consecutive bases derived from overlapping pcr clones of a recent minireovirus clinical isolate showed 52% nucleotide sequence identity with the norwalk virus sequence and, in addition, demonstrated that the genomic organizations of these two vi ...	1994	8151799
an outbreak of norwalk virus gastroenteritis associated with eating raw oysters. implications for maintaining safe oyster beds.	to determine the characteristics and the cause of an outbreak of gastroenteritis associated with eating raw oysters.	1995	7837364
detection of norwalk virus and hepatitis a virus in shellfish tissues with the pcr.	a method for the detection of norwalk virus and hepatitis a virus from shellfish tissues by pcr was developed. virus was added to the stomach and hepatopancreatic tissues of oysters or hard-shell clams, and viral nucleic acids were purified by a modification of a previously described method (r.l. atmar, t.g. metcalf, f.h. neill, and m.k. estes, appl. environ. microbiol. 59:631-635, 1993). the new method had the following advantages compared with the previously described method: (i) more rapid sa ...	1995	7487032
[gastroenteritis outbreak associated with water consumption, possibly caused by norwalk or norwalk-like virus].	it is described an acute gastroenteritis outbreak of probable hydric transmission in ontinyent (valencia). it was declared on the 31st of january, 1992 and affected 3541 people according to the declaration done by the sanitary services who attended the patients. the clinical situation was characterized by the presence of profuse and watery diarrhoea, nausea, vomiting, abdominal pain and fever or febricula.	1995	7497350
monoclonal antibodies for detection of norwalk virus antigen in stools.	monoclonal antibodies against the prototype 8fiia strain of norwalk virus were prepared and applied to an enzyme immunoassay (eia) for detecting norwalk virus in stool specimens. the monoclonal antibodies immunoprecipitated a 58-kda protein which had been produced by in vitro transcription-translation of norwalk virus cloned cdna, and they reacted by eia with recombinant norwalk virus capsid protein at a sensitivity level of 1 ng/ml. the eia detected virus in all tested samples from 15 different ...	1995	7494063
a serosurvey of water-borne pathogens amongst canoeists in south africa.	certain health risks have been associated with recreational exposure to faecally polluted water. canoeing in certain south african waters is considered to be a high risk activity with regard to schistosomiasis, gastroenteritis and possibly hepatitis. in a cross-sectional study, a serosurvey was conducted amongst canoeists to ascertain whether or not they had a higher seroprevalence to hepatitis a virus, norwalk virus and schistosoma spp. than non-canoeists. in comparisons between the two groups, ...	1995	7589269
development of an elisa to detect mx virus, a human calicivirus in the snow mountain agent genogroup.	mx virus is a snow mountain agent (sma) genogroup human calicivirus (hucv) identified in a mexican child with diarrhoea. an elisa using hyperimmune antisera to the recombinant mx virus (rmx) capsid was developed to detect sma genogroup hucvs in stool specimens. the rmx elisa detected the prototype mx virus, sma, and hawaii agent (ha), but not norwalk virus (nv) or sapporo virus. twenty-three diarrhoea stool specimens from children attending day care centres in norfolk, virginia, were positive by ...	1995	7595381
small round structured viruses (srsv): numbers are increasing.		1995	7620522
bacillus cereus and bacillus thuringiensis isolated in a gastroenteritis outbreak investigation.	during investigation of a gastroenteritis outbreak in a chronic care institution, norwalk virus was found in stool specimens from two individuals and bacterial isolates presumptively identified as bacillus cereus were isolated from four individuals (including one with norwalk virus) and spice. phage typing confirmed all bacillus clinical isolates were phage type 2. all clinical isolates were subsequently identified as b. thuringiensis when tested as a result of a related study (l. leroux, person ...	1995	7639990
an outbreak of viral gastroenteritis associated with adequately prepared oysters.	over christmas 1993, an outbreak of food poisoning occurred among guests in a hotel in south west scotland. evidence from a cohort study strongly suggested that raw oysters were the vehicle for infection, probably due to a small round structured virus (srsv). detailed enquiry about the source and preparation of the oysters revealed no evidence of any unsafe handling at any stage in the food chain, nor any evidence of bacterial contamination. it is suggested that the present standards of preparat ...	1995	7641830
expression, self-assembly, and antigenicity of a snow mountain agent-like calicivirus capsid protein.	virus-like particles were produced in insect cells infected with a recombinant baculovirus containing the capsid gene of mx virus, a mexican strain of human calicivirus. these recombinant mx (rmx) particles were morphologically similar to recombinant norwalk virus (rnv) particles as observed under an electron microscope and contained a single capsid protein with a molecular weight of 57,000, which was slightly smaller than that of rnv. this protein was immunoprecipitated by sera from volunteers ...	1995	7650166
epidemiology of norwalk virus during an outbreak of acute gastroenteritis aboard a us aircraft carrier.	a large outbreak of acute gastroenteritis occurred over a 5-week period aboard an aircraft carrier. the estimated cumulative attack rate was 13% among the 4,500-man crew. eight percent of the crew sought medical attention, nearly all of whom missed 1 day or more of work. the risk of developing illness was 2 to 3 times greater for individuals living in more crowded sleeping quarters (> 50 persons per compartment). occurrence of gastroenteritis was associated with a fourfold or more rise in norwal ...	1995	7714493
human enteric caliciviruses have a unique genome structure and are distinct from the norwalk-like viruses.	classic human enteric caliciviruses (hucvs) have a distinctive morphology and are primarily associated with pediatric acute gastroenteritis. although morphologically distinct from the small round structured viruses (srsvs), the classic hucvs are thought to be closely related and were anticipated to have a similar genome organisation. we report the first genome sequence and molecular characterisation of a classic human enteric calicivirus associated with a case of acute vomiting and diarrhoea in ...	1995	7661689
enzyme immunoassay using baculovirus-expressed human calicivirus (mexico) for the measurement of igg responses and determining its seroprevalence in london, uk.	the use of an enzyme immunoassay (eia) employing a baculovirus-expressed recombinant human calicivirus (mexico virus, mxv) for the detection of igg-specific antibodies is described. mxv appeared to be related antigenically to a strain of small round structured virus, srsv/uk4/leeds/91, which had previously been shown by solid phase immune electron microscopy (spiem) to be related to snow mountain agent (sma). one other outbreak which occurred in san anita, usa in 1980 and was due to consumption ...	1995	7561789
concentration and purification of beef extract mock eluates from water samples for the detection of enteroviruses, hepatitis a virus, and norwalk virus by reverse transcription-pcr.	in this study we developed a concentration and purification procedure to facilitate reverse transcription (rt)-pcr detection of enteric viruses in water sample concentrates obtained by conventional filter adsorption-elution methods. one liter of beef extract-glycine eluate with or without humic acid and seeded with poliovirus type 1, hepatitis a virus, and norwalk virus was used as a model system, and the eluent was further processed for rt-pcr compatibility. the sample concentration and purific ...	1995	7574592
from the centers for disease control and prevention. multistate outbreak of viral gastroenteritis associated with consumption of oysters--apalachicola bay, florida, december 1994-january 1995.		1995	7837350
use of solid-phase immune electron microscopy for classification of norwalk-like viruses into six antigenic groups from 10 outbreaks of gastroenteritis in the united states.	norwalk-like viruses observed in fecal specimens from 10 outbreaks of gastroenteritis investigated in the united states between 1987 and 1992 were analyzed by solid-phase immune electron microscopy. outbreak virus strains were classified into six antigenic groups: the four types (uk1 to uk4) previously defined in the united kingdom, norwalk virus, and the oklahoma agent that was newly defined in this study. the diversity of antigenic types demonstrated in these outbreaks was greater than previou ...	1995	7714218
hyperemesis hiemis--a sick hazard.	epidemic non-bacterial gastroenteritis or winter vomiting disease is a well recognized clinical syndrome causing significant morbidity in the general population and in semi-closed communities. the norwalk group of viruses has become established as the aetiological agents responsible for this important clinical syndrome. as a result of their historically poorly-defined taxonomic status they have been alternatively described as small round structured viruses (srsvs) which allow their differentiati ...	1995	7560989
molecular characterization of a human calicivirus with sequence relationships closer to animal caliciviruses than other known human caliciviruses.	cdna clones were produced from a morphologically typical human calicivirus (hucv) in stool specimens collected in 1982 during an outbreak of gastroenteritis in sapporo, japan. the cdna clones were generated separately in two laboratories by reverse transcriptase-polymerase chain reaction (rt-pcr) using primers 35 and 36 derived from norwalk virus. the rt-pcr product from six specimens was of the predicted size, had a continuous protein encoding frame on the positive strand, and contained glps an ...	1995	7775942
multistate outbreak of viral gastroenteritis associated with consumption of oysters--apalachicola bay, florida, december 1994-january 1995.	on january 3, 1995, the florida department of health and rehabilitative services (hrs) was notified of an outbreak of acute gastroenteritis associated with eating oysters. the subsequent investigation by hrs has identified 34 separate clusters of cases, many of which were associated with oysters harvested during december 29-31 from 13 mile area and cat point in apalachicola bay. oysters were shipped to other states, but additional clusters of illness associated with these oysters have been repor ...	1995	7808387
detection and differentiation of antigenically distinct small round-structured viruses (norwalk-like viruses) by reverse transcription-pcr and southern hybridization.	application of reverse transcription (rt)-pcr to detect small round-structured viruses (srsvs) from fecal specimens of patients with gastroenteritis has been insensitive because of the tremendous sequence heterogeneity between strains. we have designed two rt-pcr primer sets (g-1 and g-2) based on the nucleotide sequence diversity in the rna polymerase gene of srsvs belonging to two distinct genogroups represented by norwalk virus (primers g-1) and snow mountain agent (primers g-2). all 22 srsv ...	1995	7699068
human enteric caliciviridae: the complete genome sequence and expression of virus-like particles from a genetic group ii small round structured virus.	comparisons of the rna polymerase and capsid sequences of small round structured viruses (srsvs) have recently shown these are genetically diverse viruses which fall into two distinct groups. the genomes of two group i viruses, southampton and norwalk viruses have been characterized; however, similar data for the genetic group ii srsvs have not been available until now. we report here the complete genome sequence of a recent group ii srsv, lordsdale virus. the lordsdale virus genome is 7555 nt i ...	1995	7561776
characterization of srsvs using rt-pcr and a new antigen elisa.	stool samples from 451 patients involved in volunteer studies, 26 outbreaks and approximately 175 sporadic cases of acute gastroenteritis from different geographical locations in the world were tested for norwalk virus (nv) using a newly developed antigen elisa and rt-pcr. nv was detected in most outbreaks previously characterized as being of nv origin. overall, a low number of positives for nv was obtained using either rt-pcr with primers that amplified a unique region of the genome, or an elis ...	1995	7710362
specific proteolytic cleavage of recombinant norwalk virus capsid protein.	norwalk virus (nv) causes epidemic outbreaks of acute nonbacterial gastroenteritis in humans. the nv capsid is made up of a single protein, and expression of the capsid protein in baculovirus recombinants results in spontaneous assembly of the protein into virus-like particles (x. jiang, m. wang, d. y. graham, and m. k. estes, j. virol. 66:6527-6532, 1992). we have investigated whether the nv capsid protein undergoes a specific proteolytic cleavage. recombinant nv (rnv) particles were digested w ...	1995	7853506
viral shedding and fecal iga response after norwalk virus infection.	protection is not conferred by preexposure to norwalk virus (nv). by use of an elisa with baculovirus-expressed recombinant nv (rnv) capsid protein, the pattern of nv fecal shedding and the protective effect of rnv-specific fecal iga (flga) were investigated in volunteers who were repeatedly challenged with nv. after the first challenge, ill volunteers were significantly more likely than well volunteers to have nv antigen in their stool (p < .05). after challenge, antigen shedding was detected o ...	1995	7876602
diarrheal disease among military personnel during operation restore hope, somalia, 1992-1993.	the potential for widespread diarrheal disease was regarded as a substantial threat to u.s. troops participating in the early phases of operation restore hope in somalia. outpatient surveillance of 20,859 u.s. troops deployed during the first eight weeks, however, indicated that a mean of only 0.8% (range 0.5-1.2%) of personnel sought care for diarrhea each week, and in three epidemiologic surveys, < 3% of troops reported experiencing a diarrheal illness per week. despite these low overall attac ...	1995	7872452
a conserved sequence motif at the 5' terminus of the southampton virus genome is characteristic of the caliciviridae.	we have determined the 5'terminal cdna sequence for the genome of southampton virus, a recently characterized, human, small round-structured virus (srsv). genomic rna was extracted directly from a stool sample and amplified by rt-pcr by homopolymer tailing of the 3' terminus of the cdna. the additional sequence increases the overall length of the southampton virus genome by 12 nucleotides, resulting in a significant change to the genome organization by extending the first large open reading fram ...	1995	8560774
detection of small round structured viruses in shellfish by reverse transcription-pcr.	we describe the application of a previously developed sample extraction procedure to the detection of small round structured viruses (srsvs) in shellfish. initial seeding experiments showed that pcr inhibitor removal and virus recoveries were comparable to those in previous studies with poliovirus. shellfish from a range of sewage-contaminated sites were then tested for the presence of srsvs by using broadly reactive pcr primers followed by southern blotting with internal probe sites. positive r ...	1995	8534105
molecular characterisation of small round structured viruses associated with gastroenteritis in south africa.	the application of the reverse transcriptase polymerase chain reaction (rt-pcr) has enabled several morphologically and physically similar small round structured viruses (srsvs), including the prototype norwalk virus (nv), to be classified within the caliciviridae. this technique, using primers directed to the rna-dependent rna polymerase region within the orf1 of nv, was used to characterise srsvs associated with epidemic gastroenteritis in adults and sporadic paediatric gastroenteritis in sout ...	1995	8636707
broadly reactive reverse transcriptase polymerase chain reaction for the diagnosis of srsv-associated gastroenteritis.	a limitation to date of reverse transcriptase polymerase chain reactions (rt-pcrs) for the detection of small, round structured viruses (srsvs) has been that they have detected only a narrow range of srsvs due to the marked genomic diversity among strains. a total of 331 faecal samples collected from 136 separate incidents of gastroenteritis occurring in the uk between 1992 and 1994 were examined by rt-pcr employing a single primer pair (n1/e3). srsv rna was detected in samples from 93 of 101 (9 ...	1995	8636708
capsid diversity in small round-structured viruses: molecular characterization of an antigenically distinct human enteric calicivirus.	studies of antigenic variation between small round-structured viruses (srsvs) using immune electron microscopy have revealed 3 antigenic types currently circulating in the uk represented by the strains srsv/bri/93/uk, srsv/sot/91/uk and srsv/mel/89/uk. mel/89/uk rna was isolated from a 1989 school outbreak of gastroenteritis. the 3'-terminal 3435 nucleotides (excluding the poly(a) tail) were determined by rt-pcr and cdna sequencing, completing our molecular characterization of antigenically dive ...	1995	8533462
outbreaks of gastroenteritis due to norwalk-like virus in two long-term care facilities for the elderly.	in february 1993, outbreaks of gastroenteritis due to norwalk-like viruses occurred simultaneously among the elderly residents of two long-term care facilities. facility a instituted infection control measures that included increased surveillance, reinforcement of handwashing, keeping symptomatic residents in their rooms and relieving symptomatic staff of their work duties until 48 h after resolution of their symptoms. facility b instituted a more stringent set of control measures that included ...	1995	8547682
antibody prevalence and immunoglobulin igg subclass pattern to norwalk virus in sweden.	the antibody prevalence in sweden to norwalk virus (nv) was investigated using a baculovirus expressed capsid antigen. one hundred thirty-two serum samples were examined for iga, total igg and igg subclass antibodies to norwalk virus. in young children, nv igg antibody prevalence was higher than the iga prevalence, whereas no difference was found in individuals older than 21 years. the igg antibody prevalence was 50% in children below 5 years of age and increased to > 80% in individuals older th ...	1995	8551259
study of norwalk-related viruses in mexican children.	two-hundred mexican children monitored from birth to 2 years of age in a cohort study of diarrhea were tested for norwalk virus (nv) and norwalk-related virus infection. blood was collected quarterly and tested by an enzyme immunoassay (eia) using the recombinant nv (rnv) particles as antigen. stool was collected weekly and tested by an eia using hyperimmune anti-sera from animals immunized with rnv and a reverse transcription-polymerase chain reaction (rt-pcr) with primers in the rna polymerase ...	1995	8636696
isolation of cytopathic small round virus (aichi virus) from pakistani children and japanese travelers from southeast asia.	aichi virus was isolated in vero cells from 5 (2.3%) of 222 pakistani children with gastroenteritis but none was found in 91 healthy children. aichi virus was also isolated from 5 (0.7%) of 722 japanese travelers returned from tours to southeast asian countries and complained of gastrointestinal symptoms at the quarantine station of nagoya international airport in japan. of 5 japanese travelers, 3 were returning from indonesia, and 2 from thailand or malaysia. these results indicate that aichi v ...	1995	8551977
infection control. when winter makes you sick.		1995	8552486
epidemiologic applications of novel molecular methods to detect and differentiate small round structured viruses (norwalk-like viruses).	the molecular epidemiology of a large, multistate outbreak of oyster-associated gastroenteritis [kohn et al. (1995): journal of the american medical association 273:466-471. dowell et al. (1995): journal of infectious diseases 171:1497-1503.] was examined using new methods to detect small round structured viruses (srsvs) by reverse transcription-polymerase chain reaction (rt-pcr) and to characterize strains by southern hybridization and nucleotide sequencing of 81-bp of a pcr product amplified f ...	1995	8830118