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Roger I Glass

Publications and source records attributed to Roger I Glass.

At least 55 records · Page 3Linked to original sources
PubMed2005

The evolution of human group B rotaviruses: correction and an update.

The Chinese adult diarrhea rotavirus (ADRV) and the Indian CAL strains of human group B rotaviruses were reported to be conserved in genes encoding structural proteins but divergent in NSP2 and NSP3 genes, raising the questions about the origin and the evolution of these strains. We repeated sequencing of the ADRV NSP2 and NSP3 genes and demonstrated high amino acid sequence identities with the CAL NSP2 and NSP3. Here we report the consequences of publishing and interpreting incorrect nucleotide sequences and provide evidence that the ADRV and CAL strains have evolved from a common ancestor.

Amino Acid Sequence↗
PubMed2005

Norovirus and child care: challenges in outbreak control.

An infant with diarrhea attended a community playgroup. In the subsequent 48 hours, 6 of the 7 mothers and children reported gastroenteritis; fecal specimens from 5 persons tested positive for norovirus, with identical sequences. No breach of hygiene or contact with fecal matter was identified. Excluding the child with gastroenteritis from the playgroup could have prevented this outbreak.

Adult↗
PubMed2005

Update on rotavirus vaccines.

Rotavirus was discovered in 1973, and 10 years later the first report of a rotavirus vaccine clinical trial appeared. This update reviews the epidemiology of rotavirus infections, assesses past and current vaccines and presents ideas for implementation of vaccination programs in developed and developing countries.

Animals↗
PubMed2005

Noroviruses as a cause of traveler's diarrhea among students from the United States visiting Mexico.

Stool specimens from 124 international travelers with acute diarrhea were tested for the presence of enteropathogens. Noroviruses (NoVs) were the second most commonly identified enteric pathogen in diarrheal stool samples (21/124, 17%), exceeded only by enterotoxigenic Escherichia coli (50/106, 47%). This study indicates that NoV is an underappreciated cause of traveler's diarrhea.

Adolescent↗
PubMed2005

Use of active surveillance to validate international classification of diseases code estimates of rotavirus hospitalizations in children.

OBJECTIVE: National estimates of hospitalizations for rotavirus, the leading cause of acute gastroenteritis (AGE) in children, have been used to establish the need for rotavirus vaccines. A previous method directly estimated discharges by using the rotavirus-specific International Classification of Diseases (ICD) code, but this method has not been validated. Our study evaluated the sensitivity of the rotavirus ICD code among children hospitalized for AGE by using active surveillance for rotavirus at a tertiary children's hospital. DESIGN: We compared data for rotavirus-coded hospital discharges in 2000-2001 at Cincinnati Children's Hospital Medical Center with data on laboratory-confirmed cases of rotavirus obtained from active surveillance. We estimated additional rotavirus hospitalizations by extrapolating the proportion of rotavirus-positive results from active-surveillance cases to those with an unknown rotavirus status. RESULTS: Of 767 cases of AGE-related discharge codes, 103 (13%) were coded as rotavirus, 91% (94 of 103) of which were laboratory-confirmed diagnoses. Among all children discharged with an AGE-related illness, 260 (34%) were enrolled in active surveillance, of whom 155 (60%) tested positive for rotavirus. An additional 47 laboratory-confirmed rotavirus-case patients not enrolled in active surveillance yielded a total of 202 rotavirus cases and a maximum sensitivity of the rotavirus code of 47%. Extrapolation indicated that an additional 170 untested children might be rotavirus-positive, yielding a total of 372 rotavirus hospitalizations and a minimum sensitivity of the rotavirus code of 25%. CONCLUSIONS: Measurement of rotavirus-coded hospital discharges alone seems to greatly underestimate the true burden of rotavirus-associated hospitalizations. The numbers of national rotavirus hospitalization discharges may be substantially greater than previously estimated.

Acute Disease↗
PubMed2005

Norovirus and foodborne disease, United States, 1991-2000.

Efforts to prevent foodborne illness target bacterial pathogens, yet noroviruses (NoV) are suspected to be the most common cause of gastroenteritis. New molecular assays allow for better estimation of the role of NoV in foodborne illness. We analyzed 8,271 foodborne outbreaks reported to the Centers for Disease Control and Prevention from 1991 to 2000 and additional data from 6 states. The proportion of NoV-confirmed outbreaks increased from 1% in 1991 to 12% in 2000. However, from 1998 to 2000, 76% of NoV outbreaks were reported by only 11 states. In 2000, an estimated 50% of foodborne outbreaks in 6 states were attributable to NoV. NoV outbreaks were larger than bacterial outbreaks (median persons affected: 25 versus 15), and 10% of affected persons sought medical care; 1% were hospitalized. More widespread use of molecular assays will permit better estimates of the role of NoV illness and help direct efforts to control foodborne illness.

Animals↗
PubMed2005

Norovirus transmission on cruise ship.

An outbreak of norovirus gastroenteritis affected passengers on two consecutive cruises of ship X and continued on 4 subsequent cruises despite a 1-week sanitization. We documented transmission by food and person-to-person contact; persistence of virus despite sanitization onboard, including introductions of new strains; and seeding of an outbreak on land.

Caliciviridae Infections↗
PubMed2005

Rotavirus disease and its prevention.

PURPOSE OF REVIEW: Rotavirus infection is the foremost cause of severe gastroenteritis of young children worldwide. Efforts to develop safe and effective vaccines resulted in licensure of the first live oral vaccine, tetravalent, rhesus-based rotavirus vaccine (RRV-TV), which was incorporated into the US immunization schedule in 1998. Less than 1 year later, however, the vaccine was withdrawn when reports of cases of intussusception were linked to recent vaccination. This setback created significant hurdles as well as new opportunities for the development of the next generation of rotavirus vaccines. This review focuses on new information related to the clinical presentation and pathogenesis of rotavirus infection, the associated global disease burden, and the ongoing efforts to develop and introduce the next generation of rotavirus vaccines for widespread use. RECENT FINDINGS: Recent studies have confirmed that rotavirus infection is not confined only to the gut but can have extraintestinal manifestations, including viremia. Estimates of the global disease burden of rotavirus diarrhea have been refined and suggest that mortality has not declined, and that among hospitalized cases of diarrhea, the fraction associated with rotavirus has increased in many countries. In the United States, the estimated number of hospitalizations attributed to rotavirus has increased. Debate continues about the magnitude of the attributable risk of the association between RRV-TV and intussusception. Several new rotavirus vaccines are in late stages of development. One vaccine was licensed in Mexico in 2004 and a second has completed clinical trials in the United States and Europe and may be licensed within 2 to 3 years. SUMMARY: The tremendous burden of rotavirus diarrhea among children all over the world continues to drive the remarkable pace of vaccine development and the variety of approaches to creating rotavirus vaccines.

Child↗
PubMed2004

Rotavirus vaccines and the prevention of hospital-acquired diarrhea in children.

Rotavirus, the major cause of severe acute dehydrating gastroenteritis in children less than 5 years of age, is responsible for an estimated 20-50% of all hospitalizations for diarrhea and approximately 440,000 deaths annually, primarily in the developing world. Rotavirus vaccines are considered the most promising means for disease prevention. While the prime rationale for developing rotavirus vaccines has been the enormous burden of rotavirus infection leading to severe and fatal disease, a secondary benefit may be the prevention of nosocomial rotavirus diarrhea. We have reviewed the burden of intra-hospital-acquired rotavirus infections from several countries and found that in the United States alone, as many as 25% of rotavirus hospitalizations or approximately 16,000-18,000 hospitalizations each year might be due to rotavirus infections acquired within hospitals. To countries with low rotavirus-associated mortality, prevention of these infections and the resulting economic savings therefore represent an important secondary goal. Several rotavirus vaccines are in development, and two candidates are currently being tested in large-scale safety and efficacy trials. Development of safe and effective rotavirus vaccines will protect children worldwide against the severe consequences of rotavirus infections including prolonged hospitalizations for nosocomially acquired infections.

Child, Preschool↗
PubMed2004

Human caliciviruses as a cause of severe gastroenteritis in Peruvian children.

To define the role of human caliciviruses (HuCVs) in severe childhood gastroenteritis, fecal and paired serum samples from 233 Peruvian children hospitalized with gastroenteritis (case patients) and fecal samples from 248 control subjects were evaluated. Overall, 128 case patients (55%) demonstrated HuCV infection by either fecal (n=81 [35%]) or serological (n=96 [41%]) testing. HuCVs were more prevalent in fecal samples from case patients than those from control subjects (35% vs. 13%; P<.001). HuCV infection was more prevalent among case patients without another pathogen than in those who had a coinfecting pathogen (77% [40/52] vs. 49% [88/181]; P<.001). HuCVs appear to be an important cause of gastroenteritis in Peruvian children.

Antibodies, Viral↗
PubMed2004

Outbreaks of acute gastroenteritis on cruise ships and on land: identification of a predominant circulating strain of norovirus--United States, 2002.

In 2002, a sharp increase in outbreaks of norovirus-associated illness, both on cruise ships and on land, encouraged us to examine the molecular epidemiology of detected noroviruses, to identify a common strain or source. Of 14 laboratory-confirmed outbreaks on cruise ships, 12 (86%) were attributed to caliciviruses; among these 12, outbreak characteristics included continuation on successive cruises in 6 (50%), multiple modes of transmission in 7 (58%), and high (>10%) attack rates in 7 (58%). Eleven of the 12 calicivirus outbreaks were attributed to noroviruses, 7 (64%) of which were attributed to a previously unreported lineage, provisionally named "the Farmington Hills strain." From May 2002 to December 2002, 10 (45%) of 22 land-based outbreaks also were attributed to this strain. Nucleotide-sequence analysis provided insights into norovirus transmission, by documenting links among outbreaks, the introduction of strains onto ships, and viral persistence on board (despite cleaning). Control measures for outbreaks should address all routes of transmission. Better outbreak surveillance and collection of data on sequences will help to monitor norovirus strains and to identify common sources.

Acute Disease↗
PubMed2004

Molecular epidemiology of outbreaks of viral gastroenteritis in New York State, 1998-1999.

This investigation evaluated the role of Norwalk-like virus (NLV) and other viruses (rotavirus, enteric adenovirus, and enterovirus) in 11 outbreaks of acute nonbacterial gastroenteritis that occurred in multiple settings in a span of 18 months in New York State. To determine the etiology of illness, patients' stool specimens were analyzed with a combination of reverse-transcription polymerase chain reaction (RT-PCR) and nucleotide sequencing, cell culture, and ELISA diagnostic techniques. NLV was detected from all of these outbreaks, with an overall detection rate of 64% (51 of 79) for all specimens tested. Repeated attempts to isolate other viral pathogens were unsuccessful. Phylogenetic analysis of a subset of 27 specimens from these outbreaks showed the presence of both genogroup I and genogroup II NLVs. A spectrum of different nucleotide sequences were detected, demonstrating interoutbreak sequence variation and unrelated infections. NLV is a significant causative agent of diarrhea outbreaks in New York State.

Amino Acid Sequence↗
PubMed2004

Rotavirus in El Salvador: an outbreak, surveillance and estimates of disease burden, 2000-2002.

BACKGROUND: In December 2000, a large outbreak of gastroenteritis occurred in El Salvador that was associated with hospitalizations and deaths among children nationwide. Public concern was raised because the etiology was initially unknown and enteric control measures seemed ineffective. The outbreak was eventually linked to rotavirus, control measures were redirected to improving treatment with oral rehydration and surveillance was initiated to characterize the etiologic agents of gastroenteritis. METHODS: Demographic and clinical data and fecal specimens were collected from a systematic sample of children younger than 5 years old with acute gastroenteritis. Stools were tested for rotavirus, bacteria and parasites. Surveillance results were extrapolated to national data to estimate the national burden of rotavirus disease. RESULTS: Surveillance between May 2001 and April 2002 demonstrated that rotavirus has winter seasonality, was associated with vomiting and dehydration and accounted for an estimated 27% of 12,083 consultations for diarrhea. Children with rotavirus gastroenteritis were younger (median, 9 months) than those with gastroenteritis caused by other agents (median, 13 months for bacteria, 16 months for parasites). Extrapolating to national data, we estimated the risk of a child experiencing a rotavirus-related medical visit, hospitalization and death by the age of 5 years as 1:7, 1:56 and 1:531, respectively. CONCLUSIONS: The outbreak of gastroenteritis among children younger than 5 years of age between December 2000 and February 2001 represented an exaggerated rotavirus season. The surveillance activity after the outbreak suggests that rotavirus is the most common cause of diarrheal disease in El Salvador. Further surveillance could provide a sound basis for improving the response to epidemics of gastroenteritis and could provide data needed to decide whether rotavirus vaccination should be included in the national program for childhood immunizations.

Child, Preschool↗
PubMed2004

Rotavirus strain surveillance in Latin America: a review of the last nine years.

BACKGROUND: Latin America will likely be the first area in the developing world where rotavirus vaccine will be introduced into the routine childhood immunization schedule. In anticipation of that goal, we reviewed the distribution of group A rotavirus genotypes in Latin America to understand the diversity of strains to be targeted by vaccines and to identify novel strains that may pose challenges for vaccines. METHODS: We reviewed studies characterizing rotavirus strains in Latin America (published in English since 1995) that used molecular methods to type genes encoding the G and P outer capsid proteins, VP7 and VP4, and that reported data on >50 specimens. RESULTS: Fifteen studies from 5 countries met our criteria. In total, 1989 samples were characterized; 12% (233) were mixed rotavirus infections with more than 1 strain, and 20% (402) were not fully typable. Of the remaining 1354 samples that were fully typed, 83% represented the 4 common strains: P[8],G1 (40%); P[4],G2 (30%); P[8],G3 (6%); P[8],G4 (7%). The unusual strains provide interesting insights into virus evolution: some strains (G5) were regionally common; the emerging G9 strains were widely distributed; many animal-human reassortants were present; and some common serotypes (G3 and G4) were of animal origin. Also an unusual G12 serotype was recently detected in Argentina. CONCLUSIONS: The common rotavirus serotypes should remain the prime targets for vaccine development. However, the changing profile of rare strains, animal-human reassortants and nontypable strains suggest that rotavirus is constantly evolving. Laboratory surveillance is needed to monitor rotavirus strains now in circulation and to detect those that might escape the immunity induced by vaccines or represent vaccine strains entering the environment.

Capsid Proteins↗