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R I Glass

Publications and source records attributed to R I Glass.

At least 73 records · Page 4Linked to original sources
PubMed1999

Sequence analysis of the gene encoding VP4 of a bovine group C rotavirus: molecular evidence for a new P genotype.

Nucleotide sequence of the bovine group C rotavirus Shintoku strain gene 3 was determined. Segment 3 is 2253 nucleotides (nt) in length and contains a long open reading frame (ORF) beginning at nt 22 and terminating at nt 2223. This ORF encodes a polypeptide of 733 amino acids with a predicted molecular mass of 83 kDa. The deduced gene 3 amino acid sequence shares 79% and 73% identities with VP4 of the porcine Cowden and human Bristol strains, respectively. Lack of high amino acid sequence homology in VP4 of bovine, porcine, and human group C rotaviruses indicates that the Shintoku strain represents a new P genotype.

Amino Acid Sequence↗
PubMed1999

Enteropathogens and other factors associated with severe disease in children with acute watery diarrhea in Lima, Peru.

To evaluate enteropathogens and other factors associated with severe disease in children with diarrhea, 381 children <5 years of age with diarrhea and moderate to severe dehydration (in-patients) and 381 age-, sex-, and date-of-visit-matched children with mild diarrhea (out-patients) presenting to a hospital in Peru, were studied. Rotavirus was detected in 52% of the in-patients and 35% of the out-patients (odds ratio [OR]=2.3, 95% confidence interval [95% CI]= 1.6-3.2); 95% of the rotaviruses among in-patients were of serotypes G1-G4. The risk of severe diarrhea was particularly great in children who were not exclusively breast-fed in early infancy and who also lacked piped water in their homes (for children with both characteristics OR=6.8, 95% CI=3.6-12.8). The high prevalence of rotavirus and its association with severe diarrhea underscores the need for rotavirus vaccines. Interventions to educate mothers and improve access to safe water should augment the impact of rotavirus vaccines in preventing severe diarrhea.

Animals↗
PubMed1999

Identification of a distinct common strain of "Norwalk-like viruses" having a global distribution.

"Norwalk-like viruses" (NLVs) are the most common cause of outbreaks of nonbacterial gastroenteritis. During molecular surveillance of NLV strains from 152 outbreaks of gastroenteritis that occurred in the US between August 1993 and July 1997, we identified an NLV strain that predominated during the 1995-1996 season. The "95/96-US" strain caused 60 outbreaks in geographically distant locations within the US and was identified, by sequence comparisons, in an additional 7 countries on 5 continents during the same period. This is the first demonstration linking a single NLV strain globally and suggests that the circulation of these strains might involve patterns of transmission not previously considered. The diagnostic techniques are now available to establish a global network for surveillance of NLV strains that would highlight the importance of NLVs worldwide and allow molecular identification of common strains having a global distribution so as to consider interventions for their control.

Caliciviridae Infections↗
PubMed1999

An outbreak of acute gastroenteritis in a geriatric long-term-care facility: combined application of epidemiological and molecular diagnostic methods.

OBJECTIVE: To assess possible transmission modes of, and risk factors for, gastroenteritis associated with Norwalk-like viruses (NLVs) in a geriatric long-term-care facility. METHODS: During a prolonged outbreak of acute gastroenteritis, epidemiological data on illness among residents and employees were collected in conjunction with stool, vomitus, and environmental specimens for viral testing. NLVs were identified by electron microscopy in stool and vomitus specimens, and further characterized by reverse-transcriptase polymerase chain reaction and nucleotide sequencing. Potential risk factors were examined through medical-record review, personal interview, and a self-administered questionnaire sent to all employees. RESULTS: During the outbreak period, 52 (57%) of 91 residents and 34 (35%) of 90 employees developed acute gastroenteritis. Four case-residents were hospitalized; three residents died at the facility shortly after onset of illness. A point source was not identified; no association between food or water consumption and gastroenteritis was identified. A single NLV strain genetically related to Toronto virus was the only pathogen identified. Residents were at significantly higher risk of gastroenteritis if they were physically debilitated (relative risk [RR], 3.5; 95% confidence interval [CI95], 1.0-12.9), as were employees exposed to residents with acute gastroenteritis (RR, 2.6; CI95, 1.1-6.5) or ill household members (RR, 2.3; CI95, 1.4-3.6). Adherence to infection control measures among the nursing staff may have reduced the risk of gastroenteritis, but the reduction did not reach statistical significance. CONCLUSIONS: In the absence of evidence for food-borne or waterborne transmission, NLVs likely spread among residents and employees of a long-term-care facility through person-to-person or airborne droplet transmission. Rapid notification of local health officials, collection of clinical specimens, and institution of infection control measures are necessary if viral gastroenteritis transmission is to be limited in institutional settings.

Adult↗
PubMed1999

First rotavirus vaccine licensed: is there really a need?

The first rotavirus vaccine was licensed in the United States on 31 August 1998 for the prevention of severe rotavirus diarrhea in children. Despite this landmark in new vaccines, many pediatricians and public health professionals in Europe are uncertain of the need for this vaccine for the routine immunization of infants. In Europe, ample evidence suggests that rotavirus is the most common cause of hospitalizations for severe diarrhea among children, but proper studies documenting the disease burden of rotavirus or the cost-effectiveness of a rotavirus immunization program have only been conducted in the United Kingdom following epidemiologic models used in the United States. All children are infected with rotavirus during their first few years of life, 30-50% of diarrheal hospitalizations among children <5 years are due to this agent, and, by the age of 5 years, between 1 in 40 and 1 in 77 children in Europe and the United States may be hospitalized for rotavirus. The first vaccine is a live, oral preparation combining four different serotypes of rotavirus and administered in three doses with other childhood immunizations. The good efficacy against severe rotavirus diarrhea, the low risk of adverse side effects and the positive cost-effectiveness equation have led the two major immunization advisory groups in the U.S. to recommend this vaccine for routine use in American infants. European physicians and policy-makers should re-examine the epidemiology and disease burden of rotavirus diarrhea now that an effective method of prevention is at hand.

Child↗
PubMed1999

Comparison of enzyme immunoassay and reverse transcriptase PCR for identification of serotype G9 rotaviruses.

While only four globally important rotavirus G serotypes (1 to 4) have been documented, many studies suggest that serotype G9 viruses may be widely distributed and more important than previously recognized. We have evaluated 10 serotype G9 rotavirus-neutralizing monoclonal antibodies (MAbs) directed to VP7, which bound by direct enzyme immunoassay (EIA) to P1A[8], G9 rotaviruses F45, WI61, and AU32, for their ability to recognize the New Delhi G9 rotavirus 116E. Only one MAb (MAb F45:1) bound to P[11], G9 virus 116E to a high titer by EIA. This MAb was incorporated into an indirect EIA for G serotyping, which was validated with prototype cultivable human rotaviruses of G types 1 to 4 and 9. The EIA was compared with genotyping by reverse transcriptase PCR (RT-PCR) under code for the determination of the G types of rotaviruses obtained from neonates in New Delhi, India. The sensitivities of RT-PCR and EIA (after two additional freeze-thaw cycles) for the typing of G9 rotaviruses were 91 and 86%, respectively, for 24 culture-adapted rotavirus strains. The untypeable culture-adapted rotavirus samples also were unreactive with VP7 group antigen-reactive MAb 60. After two additional freeze-thaw cycles, only 26 of 42 (62%) of stools containing rotavirus typed as G9 by RT-PCR were positive for G9 rotavirus by EIA. Stools containing rotavirus untypeable by EIA contained significantly less MAb 60-reactive VP7 antigen (P = 0. 0001) than the stools containing typeable rotavirus. Thus, RT-PCR genotyping was the more sensitive method for determination of G9 type, but a serotype was readily determined in rotavirus samples containing MAb 60-reactive VP7 antigen by an EIA that incorporates MAb F45:1.

Antibodies, Monoclonal↗
PubMed1999

Evidence of high-frequency genomic reassortment of group A rotavirus strains in Bangladesh: emergence of type G9 in 1995.

We characterized 1,534 rotavirus (RV) strains collected in Bangladesh from 1992 to 1997 to assess temporal changes in G type and to study the most common G and P types using reverse transcription-PCR, oligonucleotide probe hybridization, and monoclonal antibody-based enzyme immunoassay. Results from this study combined with our previous findings from 1987 to 1991 (F. Bingnan et al., J. Clin. Microbiol. 29:862-868, 1991, and L. E. Unicomb et al., Arch. Virol. 132:201-208, 1993) (n = 2,515 fecal specimens) demonstrated that the distribution of the four major G types varied from year to year, types G1 to G4 constituted 51% of all strains tested (n = 1,364), and type G4 was the most prevalent type (22%), followed by type G2 (17%). Of 351 strains tested for both G and P types, three globally common types, type P[8], G1, type P[4], G2, and type P[8], G4, comprised 45% (n = 159) of the strains, although eight other strains were circulating during the study period. Mixed G and/or P types were found in 23% (n = 79) of the samples tested. Type G9 RVs that were genotype P[6] and P[8] with both long and short electrophoretic patterns emerged in 1995. The finding of five different genotypes among G9 strains, of which three were frequently detected, suggests that they may have an unusual propensity for reassortment that exceeds that found among the common G types. We also detected antigenic changes in serotypes G2 and G4 over time, as indicated by the loss of reactivity with standard typing monoclonal antibodies. Our data suggest that a vaccine must provide protection against type G9 RVs as well as against the four major G types because G9 strains constituted 16% (n = 56) of the typeable RV strains and have predominated since 1996.

Antibodies, Monoclonal↗
PubMed1999

Trends in diarrhea-associated hospitalizations among American Indian and Alaska native children, 1980-1995.

OBJECTIVE: To describe trends in diarrhea- associated hospitalizations among American Indian and Alaska Native (AI/AN) children and to estimate the morbidity from rotavirus. DESIGN: Retrospective analysis of Indian Health Service hospital discharge records. PATIENTS: AI/AN children 1 month through 4 years of age with a diarrhea-associated diagnosis listed on the hospital discharge record. SETTING: Hospitals on or near US Indian reservations from 1980 through 1995. RESULTS: During 1980 through 1995, 21 669 diarrhea-associated hospitalizations were reported among AI/AN children. The annual incidence of diarrhea-associated hospitalizations declined by 76% from 276 per 10 000 in 1980 to 65 per 10 000 in 1995. The median length of hospital stay decreased from 4 days during 1980-1982 to 2 days during 1993-1995. Diarrhea-associated hospitalizations peaked during the winter months (October through March), especially among children 4-35 months of age, with the peaks appearing first in the Southwest during October and moving to the East in March. In the early years of the study (1980-1982), the rate of diarrhea-associated hospitalizations among AI/AN children (236 per 10 000) was greater than the national rate (136 per 10 000). By the end of the study period (1993-1995), the rate for AI/AN children (71 per 10 000) was similar to the national rate (89 per 10 000), although the rate for AI/AN infants remained higher than the national rate for infants. CONCLUSIONS: Diarrhea-associated hospitalization rates for AI/AN children have declined to a level similar to that of the national population. Rotavirus may be an important contributor to diarrheal morbidity among AI/AN children, underscoring the need for vaccines against this pathogen.

Alaska↗
PubMed1999

Use of state hospital discharge data to assess the morbidity from rotavirus diarrhea and to monitor the impact of a rotavirus immunization program: A pilot study in Connecticut.

OBJECTIVES: Now that rotavirus vaccines have been licensed and recommended for routine immunization of US infants, there is an urgent need for data to assess the morbidity from rotavirus diarrhea and to monitor the impact of a rotavirus immunization program. In a pilot study, we have assessed the usefulness of state hospital discharge data on diarrhea in children to provide this information by examining data from Connecticut. DESIGN: Retrospective analysis of discharge records from acute care, nongovernmental hospitals in Connecticut. Patients. Children 1 month through 4 years of age with a diarrhea-associated diagnosis listed on the discharge record. Setting. Connecticut, 1987 through 1996. RESULTS: During the 10-year study period, a total of 11 324 diarrhea-associated hospitalizations (49.4 hospitalizations per 10,000 children) were reported. Diarrhea-associated hospitalizations peaked during February through April, especially among children 4 to 35 months of age. The seasonality and age distribution of diarrhea-associated hospitalizations of presumed noninfectious and viral etiologies resembled those of rotavirus-associated hospitalizations. During 1993 to 1996, rotavirus was coded for 10.4% of diarrhea-associated hospitalizations increasing from 8.6% in 1993 to 14.7% in 1996. The unadjusted median cost of a diarrhea-associated hospitalization during 1987 to 1996 and 1993 to 1996 was $1,941 and $2,428, respectively. CONCLUSIONS: Diarrhea causes substantial morbidity in children from Connecticut. The winter seasonal peak of diarrhea-associated hospitalizations in children 4 to 35 months of age coinciding with the peak of rotavirus-specific hospitalizations suggests that rotavirus is an important contributor to the overall morbidity. Although our findings suggest incomplete coding of rotavirus cases, state hospital discharge data should provide sensitive and timely information to monitor the impact of a rotavirus immunization program in Connecticut.

Child, Preschool↗
PubMed1999

Rotavirus G and P types in children with acute diarrhea in Blantyre, Malawi, from 1997 to 1998: predominance of novel P[6]G8 strains.

One hundred rotavirus strains detected in children with acute diarrhea in Blantyre, Malawi, between July 1997 and January 1998 were characterized for G (VP7) and P (VP4) types by using multiplex, heminested, reverse transcription-polymerase chain reaction. A novel P[6]G8 rotavirus strain was identified in 42% of the specimens. The remaining strains comprised P[8]G3 (20%), P[6]G3 (10%), P[4]G8 (9%), P[6]G9 (3%), P[8]G4 (2%), P[6]G4 (2%), and P[4]G3 (1%). Rotavirus strains with mixed G or P types were identified in 2% of the specimens. Nine percent of the strains were nontypeable with the primers used. The P[6] genotype was identified in 57% of strains overall. This first description of serotype G8 rotavirus as a predominant strain has important implications for vaccine development in Africa. The finding of novel P/G combinations (P[6]G8 and P[4]G8) highlights the extraordinary diversity of rotaviruses in some countries.

Acute Disease↗
PubMed1999

An outbreak of group C rotavirus gastroenteritis among children attending a day-care centre in Belém, Brazil.

In August 1993, an outbreak of group C rotavirus-associated gastroenteritis occurred among children attending a day-care centre in Belém, Brazil. Of the 64 children, 21 (33%) became ill. Group C rotavirus was identified in faecal specimens from 8 (38%) children with diarrhoea by electron microscopy (EM) and an enzyme immunoassay (EIA), using antibodies specific to the Cowden strain of porcine group C rotavirus. By polyacrylamide gel electrophoresis (PAGE), a pattern similar to that of group C rotavirus was observed in 5 (62.5%) of the 8 EM- and EIA-positive samples. These 5 faecal samples were confirmed to be positive for group C rotavirus by reverse transcriptase-polymerase chain reaction, using specific VP6 and VP7 primers. This is the first report of an outbreak of diarrhoea in North Brazil associated with group C rotavirus. These findings suggest that group C rotavirus may be an important aetiological agent of diarrhoea in this region, which requires further study.

Brazil↗
PubMed1998

Cost-effectiveness analysis of a rotavirus immunization program for the United States.

CONTEXT: Rotavirus is the most common cause of severe diarrhea in children, and a live, oral vaccine may soon be licensed for prevention. OBJECTIVE: To estimate the economic impact of a national rotavirus immunization program in the United States. DESIGN: Cost-effectiveness was analyzed from the perspectives of the health care system and society. A decision tree used estimates of disease burden, costs, vaccine coverage, efficacy, and price obtained from published and unpublished sources. INTERVENTION: The proposed vaccine would be administered to infants at ages 2, 4, and 6 months as part of the routine schedule of childhood immunizations. MAIN OUTCOME MEASURES: Total costs, outcomes prevented, and incremental cost-effectiveness. RESULTS: A routine, universal rotavirus immunization program would prevent 1.08 million cases of diarrhea, avoiding 34000 hospitalizations, 95000 emergency department visits, and 227000 physician visits in the first 5 years of life. At $20 per dose, the program would cost $289 million and realize a net loss of $107 million to the health care system-$103 per case prevented. The program would provide a net savings of $296 million to society. Threshold analysis identified a break-even price per dose of $9 for the health care system and $51 for the societal perspective. Greater disease burden and greater vaccine efficacy and lower vaccine price increased cost-effectiveness. CONCLUSIONS: A US rotavirus immunization program would be cost-effective from the perspectives of society and the health care system, although the cost of the immunization program would not be fully offset by the reduction in health care cost of rotavirus diarrhea unless the price fell to $9 per dose.

Child↗
PubMed1998

Diarrheal mortality in US infants. Influence of birth weight on risk factors for death.

OBJECTIVES: To examine diarrhea-associated deaths among very low-birth-weight (VLBW) (< 1500 g) infants and low- and normal-birth-weight (LNBW) (> or = 1500 g) infants at birth and to identify specific interventions to prevent these deaths. DESIGN: Retrospective analyses of linked infant and birth death data on diarrhea of all causes compiled by the National Center for Health Statistics, Centers for Disease Control and Prevention, Atlanta, Ga. PATIENTS: Infants aged 27 days through 11 months who died with diarrhea. SETTING: United States, 1991. RESULTS: A majority (56%, n = 143) of the 257 diarrhea-associated deaths reported among US infants in 1991 occurred among VLBW infants. Compared with LNBW infants, VLBW infants had a 100-fold greater diarrheal mortality (269 deaths per 100,000 live births for VLBW infants vs 2.8 deaths per 100,000 live births for LNBW infants), died at a younger age, and more often died in the hospital. Diarrhea-associated deaths among VLBW infants were strongly associated with prematurity and a low 1-minute Apgar score whereas African American race, less maternal education, and a low 1-minute Apgar score were associated with increased diarrheal mortality among LNBW infants. CONCLUSIONS: Infants of VLBW are at an increased risk for diarrheal deaths and new efforts are required to understand and improve the diagnosis of and therapy for diarrhea among these infants. For LNBW infants, diarrheal deaths remain a social problem and efforts need to focus on improved education and home-based rehydration therapy for children whose mothers fit the high-risk profile and who may lack adequate access to health care.

Birth Weight↗
PubMed1998

An outbreak of viral gastroenteritis associated with consumption of sandwiches: implications for the control of transmission by food handlers.

Although food handlers are often implicated as the source of infection in outbreaks of food-borne viral gastroenteritis, little is known about the timing of infectivity in relation to illness. We investigated a gastroenteritis outbreak among employees of a manufacturing company and found an association (RR = 14.1, 95% CI = 2.0-97.3) between disease and eating sandwiches prepared by 6 food handlers, 1 of whom reported gastroenteritis which had subsided 4 days earlier. Norwalk-like viruses were detected by electron microscopy or reverse transcriptase-polymerase chain reaction (RT-PCR) in stool specimens from several company employees, the sick food handler whose specimen was obtained 10 days after resolution of illness, and an asymptomatic food handler. All RT-PCR product sequences were identical, suggesting a common source of infection. These data support observations from recent volunteer studies that current recommendations to exclude food handlers from work for 48-72 h after recovery from illness may not always prevent transmission of Norwalk-like viruses because virus can be shed up to 10 days after illness or while exhibiting no symptoms.

Caliciviridae Infections↗
PubMed1998

Molecular epidemiology of "Norwalk-like viruses" in outbreaks of gastroenteritis in the United States.

Fecal specimens from 90 outbreaks of nonbacterial gastroenteritis reported to 33 state health departments from January 1996 to June 1997 were examined to determine the importance of and to characterize "Norwalk-like viruses" (NLVs) in these outbreaks. NLVs were detected by reverse transcription-polymerase chain reaction in specimens from 86 (96%) of 90 outbreaks. Outbreaks were most frequent in nursing homes and hospitals (43%), followed by restaurants or events with catered meals (26%); consumption of contaminated food was the most commonly identified mode of transmission (37%). Nucleotide sequence analysis showed great diversity between strains but also provided evidence indicating the emergence of a common, predominant strain. The application of improved molecular techniques to detect NLVs demonstrates that most outbreaks of nonbacterial gastroenteritis in the United States appear to be associated with these viruses and that sequence analysis is a robust tool to help link or differentiate these outbreaks.

Aged↗
PubMed1998

Hospitalizations associated with rotavirus diarrhea in the United States, 1993 through 1995: surveillance based on the new ICD-9-CM rotavirus-specific diagnostic code.

The introduction of a specific International Classification of Diseases code for rotavirus diarrhea in 1992 prompted examination of the National Hospital Discharge Survey (NHDS) for trends in rotavirus-associated hospitalizations among US children aged 1 month through 4 years. During 1993-1995, 13.5% of hospitalizations were associated with diarrhea (n = 162,478/year). Rotavirus was the most common pathogen identified, coded in 16.5% of diarrhea cases (n = 26,798/year), and increased from 13.3% in 1993 to 18.9% in 1995. The age distribution and seasonality of hospitalizations of presumed noninfectious and viral etiology resembled those associated with rotavirus. Rotavirus was reported as a cause of diarrhea more frequently by hospitals that were large (> or =100 beds), proprietary-owned, or in the West/Midwest. Although these findings suggest incomplete detection of rotavirus diarrhea cases, the large number of rotavirus-associated hospitalizations underscores the need for vaccines and indicates that NHDS data could be used to monitor the impact of a US rotavirus immunization program.

Age Factors↗
PubMed1998

Epidemiology of diarrheal disease among children enrolled in four West Coast health maintenance organizations. Vaccine Safety Datalink Team.

BACKGROUND: We used information from the Vaccine Safety Datalink (VSD) about approximately 1 million children enrolled in four health maintenance organizations to assess the morbidity from diarrhea and estimate the disease burden of rotavirus. METHODS: We examined trends of diarrhea-associated hospitalizations and emergency room (ER) visits among VSD children ages 1 month through 4 years during October, 1992, through September, 1994 (two rotavirus seasons) and estimated the morbidity from rotavirus on the basis of characteristic patterns of age and seasonality. RESULTS: Overall diarrhea was associated with 6.3% of hospitalizations and 4% of ER visits. During a child's first 5 years of life, we estimated that 1 in 57 was hospitalized and 1 in 21 required an ER visit because of diarrhea. Each year the number of diarrhea-associated hospitalizations and ER visits was greatest in winter among children ages 4 to 23 months and peaked in November in California and during February in Oregon and Washington. The winter seasonality of diarrhea-associated hospitalizations reflected the trends for diarrhea of presumed noninfectious and viral etiologies, which together accounted for most (92.9%) hospitalizations. CONCLUSIONS: Diarrhea is an important cause of morbidity among VSD children. The epidemiologic patterns of diarrhea-associated hospitalizations and ER visits resembled those reported previously for rotavirus diarrhea, suggesting that rotavirus may be a major contributor to the overall morbidity from diarrhea. Enhanced surveillance by screening for rotavirus in a sample of children with diarrhea will permit a more accurate assessment of the disease burden of this pathogen and the cost effectiveness of a rotavirus immunization program.

California↗