Search PubMed⌕ Search

Biomedical subjects

U D Parashar

Publications and source records attributed to U D Parashar.

32 records · Page 2Linked to original sources
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

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↗
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

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

Topical antimicrobials applied to the umbilical cord stump: a new intervention against neonatal tetanus.

BACKGROUND: Previous case-control studies of neonatal tetanus (NNT), a leading cause of infant mortality in developing countries, have suggested that antimicrobials applied after delivery to the umbilical cord stump may protect against this disease. However, assessment of their protective effect has been limited by the low prevalence of antimicrobial use in developing countries. METHODS: We conducted a population-based, matched, case-control study to assess the use of antimicrobials and other factors potentially related to NNT in rural parts of Bangladesh. We studied 359 cases (infants who were normal at birth but who died between the 3rd and 30th day of life after an illness characterized by signs of NNT), each matched to three living controls for gender, residence, and date of birth. RESULTS: In univariate analyses, the application of either antibiotics or disinfectants at delivery, and the continuous or any application of disinfectants were protective against NNT. The application of antibiotics at delivery (odds ratio [OR] = 0.21, P = 0.019), hand washing by the delivery attendant (OR = 0.64, P = 0.005), and prior maternal immunization with tetanus toxoid (OR = 0.50, P < 0.001) remained protective in conditional logistic-regression analyses. Application of animal dung to the umbilical stump (OR = 2.31, P = 0.047) was hazardous. CONCLUSIONS: Effective and inexpensive topical antimicrobials provide a new prevention opportunity that could be used by traditional birth attendants and mothers to provide additional benefits to NNT control programmes based on maternal immunization with tetanus toxoid. Promotion of hygienic delivery and cord-care practices and increasing tetanus toxoid coverage remain cornerstones for the prevention of NNT deaths.

Administration, Topical↗
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↗
PubMed1998

Detection and characterization of novel rotavirus strains in the United States.

We recently established a rotavirus strain surveillance system in the United States to monitor the prevalent G serotypes before and after the anticipated implementation of a vaccination program against rotavirus and to identify the emergence of uncommon strains. In this study, we examined 348 rotavirus strains obtained in 1996 to 1997 from children with diarrhea in 10 U.S. cities. Strains were characterized for P and G types, subgroups, and electropherotypes by using a combination of monoclonal antibody immunoassay, reverse transcription-PCR, and hybridization. The four strains most commonly found worldwide comprised 83% of the isolates (P[8]G1, 66.4%; P[4]G2, 8.3%; P[8]G3, 6.9%; P[8]G4, 1.4%), but 9.2% were unusual strains (P[6]G9, 5.5%; P[8]G9, 1.7%; P[6]G1, 1.4%; and P[4]G1 and P[8]G2, 0. 3% each). Strains not typeable for P or G type accounted for 5.5% of the total, while 2.3% of the strains had more than one G type (mixed infections). All P[6]G9 strains tested had short electropherotypes and subgroup I specificity and were detected in 4 of 10 cities, while P[8]G9 strains had long electropherotypes and subgroup II VP6 antigens. Both sequence analysis of the VP7 open reading frame (about 94 to 95% amino acid identity with the VP7 gene of G9 prototype strain WI61) and binding to a G9-specific monoclonal antibody strongly suggest that U.S. G9 strains belong to serotype G9. The high detection rates of unusual rotaviruses with G9 (7.2%) or P[6] (6.9%) specificity in multiple U.S. cities suggest the emergence of new strains or inadequate diagnosis in the past. The epidemiologic importance of these strains remains to be determined.

Antibodies, Monoclonal↗
PubMedDate not supplied

"Norwalk-like viruses" as a cause of foodborne disease outbreaks.

While outbreaks of foodborne disease remain an important public health concern, their aetiology is not identified in a majority of instances. In targeted studies, the application of newly developed molecular assays has demonstrated that a large proportion of these outbreaks may be caused by the "Norwalk-like viruses" (NLV), a genus of genetically related viruses belonging to the family Caliciviridae. NLV outbreaks associated with consumption of faecally contaminated oysters are frequently reported and can best be controlled by preventing contamination of oyster-harvesting waters. Infectious foodhandlers are another frequent source of contamination, and such transmission can be minimised by exclusion of ill foodhandlers and the maintenance of strict personal hygiene. Molecular assays have greatly refined the epidemiological investigation of foodborne NLV outbreaks, allowing the linking of outbreaks in different locations and permitting the identification of the virus in the implicated vehicle. The development of simpler and more sensitive assays and their use on a broader scale will assist in defining the true burden of foodborne NLV outbreaks and improve strategies for their prevention and control.

Animals↗
PubMedDate not supplied

Rotavirus.

Rotavirus, the most common diarrheal pathogen in children worldwide, causes approximately one third of diarrhea-associated hospitalizations and 800,000 deaths per year. Because natural infection reduces the incidence and severity of subsequent episodes, rotavirus diarrhea might be controlled through vaccination. Serotypespecific immunity may play a role in protection from disease. Tetravalent rhesus-human reassortant rotavirus vaccine (RRV-TV) (which contains a rhesus rotavirus with serotype G3 specificity and reassortant rhesus-human rotaviruses with G1, G2, and G4 specificity) provides coverage against the four common serotypes of human rotavirus. In clinical trials in industrialized countries, RRV-TV conferred 49% to 68% protection against any rotavirus diarrhea and 61% to 100% protection against severe disease. This vaccine was licensed by the U.S. Food and Drug Administration on August 31, 1998, and should be cost-effective in reducing diarrheal diseases in industrialized countries. The vaccine's efficacy and cost-effectiveness in developing countries should be evaluated.

Animals↗