Background: Rotavirus is one of the most common diarrheal diseases in children less than 5 years of age. Rotavirus vaccines have greatly reduced this burden in the United States. An examination was conducted to determine possible disparities in RV vaccination rates compared to DTaP. Methods: Children were actively enrolled during two rotavirus seasons from January-June of 2010 and 2011 in the Emergency Departments (ED) and inpatient floors from all Children's Healthcare of Atlanta (CHOA) sites (Scottish Rite, Egleston, and Hughes Spalding) with acute gastroenteritis (AGE). Data and a stool sample were collected from enrolled children and samples were tested for presence of rotavirus using an enzyme immunoassay (EIA) kit (Rotaclone). Vaccination records were abstracted from the state immunization registry and primary healthcare providers to examine complete and incomplete vaccination status. This cohort of children with vaccination records were used for this analysis. Cases were identified as children receiving a complete RV dose series and controls were identified as children with incomplete RV doses. A logistic regression model was used to determine disparities seen amongst children with incomplete vaccination status. Results: Of the 660 patients that were approached for this study, 414 participants were included in this retrospective cohort analysis. 46.9% had incomplete rotavirus vaccination status and were more likely to be positive for rotavirus AGE (OR 1.76, 95% CI 1.46-2.13). Black infants had a higher rate of incomplete RV compared to whites (p-value 0.0006). When controlling for covariates, racial differences were no longer significant (OR 1.37 95% CI 0.77-2.57); however household size (p-value 0.0343), age at onset of illness (p-value 0.0061), and DTaP vaccination status (p-value < 0.0001) were all significant in determining vaccination status for children. Conclusions: Racial disparities and socioeconomic differences are not evident in determining rotavirus vaccination rates; however, household size, a possible social determinant, has an effect on RV status. In addition, timely vaccinations are important in preventing incomplete RV vaccination status, due to RV vaccine age restrictions.

Rotavirus diarrhea causes a disproportionate amount of the world's childhood mortality. Approximately 611,000 children die each year due to complications of rotavirus infections. In this study we evaluate rotavirus vaccination using four different methods. We look at the epidemiological history of the disease and vaccination against the disease, then we evaluate the effectiveness of vaccination first using a cost-benefit analysis, then using an ordinary differential equations based model, and last through computer simulations in Matlab. We do a traditional cost-benefit analysis as suggested by the Public Health Service of the United States to evaluate the costs and benefits of implementing a rotavirus vaccination program in Egypt with the RotaRix vaccine. Our results show that given the current standards of care in Egypt, it would be more cost-beneficial for Egypt not to use the rotavirus vaccine. We formulate a model of the spread of rotavirus diarrhea based on a continuous time ordinary differential equations model of two viral strains of influenza. We expand this influenza model to include the case of co-infection. We further expand the original model to explore the effects of vaccination. We used computer simulations to further analyze the effect of vaccination as a control method. These simulations show that the spread of the disease is highly sensitive to the levels of cross-immunity between the strains, and the level of vaccination in the population. We found that the dynamics observed in the new model are similar to the dynamics observed in the original model. We found the minimum levels of vaccination necessary in this model to eradicate severe rotavirus disease and minimum levels of cross-immunity between the strains

Rotavirus is the most common cause of severe gastroenteritis among children <5 years of age worldwide and is responsible for 453,000 deaths among children in this age group. More than half of these deaths occur in sub-Saharan Africa. Because of the tremendous global burden of rotavirus, vaccine development and introduction has been a high priority for several international agencies, including the World Health Organization (WHO) and GAVI. Two live, attenuated, orally administered rotavirus vaccines, a pentavalent bovine-human reassortant vaccine (RV5; RotaTeq® (Merck and Co, Inc, Pennsylvania)) and a monovalent vaccine (RV1; Rotarix™ (GSK Biologicals, Rixensart, Belgium)) based on a human rotavirus strain, are licensed and available for use in many countries worldwide. Pre-licensure clinical trials of each of these vaccines in high and middle-income countries demonstrated high efficacy (85-98%) against severe rotavirus disease. Further studies conducted in low-income countries of Asia and Africa found modest efficacy (50%-70%) of these vaccines against severe rotavirus disease. However, the public health impact of vaccination (in terms of burden of severe rotavirus disease prevented by vaccinating a given number of children) is greater in developing countries because of the substantially higher baseline rotavirus disease burden in these settings. In 2009, the World Health Organization recommended the inclusion of rotavirus vaccine in the national immunization programs of all countries globally and particularly in those countries with high child mortality due to diarrhea. Of the 16 countries recently approved by GAVI for rotavirus vaccine introduction, 12 countries are located in Africa. As rotavirus vaccines are introduced into national immunization programs, monitoring their impact is a high priority for several reasons. There is a need to assess the effectiveness of these vaccines in routine use to ensure it parallels that of pre-licensure trials, particularly when used in developing countries. Assessing the impact of vaccination on disease burden in countries such as Rwanda will be vital to understanding the full public health benefit of the vaccine. The primary purpose of this program evaluation is to determine the impact of pentavalent rotavirus vaccine on rotavirus and all-cause diarrhea morbidity following introduction into the national immunization program in Rwanda in May 2012. Additionally, this evaluation will document changes in circulating strains over time pre- and post-vaccine introduction. It will also strengthen support for economic evaluation of treating diarrhea versus introduction of new vaccine in routine immunization. Methodology Various studies have been implemented since 2011 in the health sector in Rwanda to reach the goal of this thesis. First, we analyzed data for all-cause, non-bloody diarrheal disease among children <5 years of age from the routine health management information system (HMIS) in Rwanda from January 2008 through December 2011, The objective of this analysis was to determine whether routinely collected health information on national diarrhea hospitalizations, in-hospital deaths, and outpatient visits can be used to monitor the impact of rotavirus vaccine. We used data from the health management information system (HMIS) in Rwanda to describe trends in all-cause, non-bloody diarrhea hospitalizations and outpatient visits among children <5 years of age from 2008 to 2011 prior to vaccine introduction. Second, we evaluated the economic burden attributable to hospitalization for diarrhea among children aged less than 5 years in Rwanda. This was a prospective costing study where medical records and hospital bills for children admitted with diarrhea at 3 hospitals were collected to estimate costs. Interviews with the child’s caregivers provided medical costs incurred before and after hospitalization and the household costs. Third, we analyzed and tried to understand the introduction and delivery cost per dose or per child of the three new vaccines in Rwanda including the rotavirus vaccine for domestic and external financial resource mobilization. Fourth, we determined the rotavirus prevalence rates and circulating genotypes directly pre- and post-introduction of the RotaTeq rotavirus vaccine in May 2012. Stool samples were collected from 1,847 children <5 admitted to 8 surveillance sites for acute gastroenteritis (AGE) and tested for rotavirus antigens by enzyme immunoassay. Fifth, to monitor the effect of rotavirus vaccine in Rwanda, we studied trends in the number of hospital admissions for diarrhea and rotavirus before and after the introduction of the rotavirus vaccine. We conducted a time-series analysis to examine trends in admissions to hospital for non-bloody diarrhea in children younger than 5 years in Rwanda between Jan 1, 2009, and Dec 31, 2014, using monthly discharge data from the HMIS.Result All-cause, non bloody diarrheal hospitalizations and outpatient visits among children <5 years of age in Rwanda from 2008 to 2011 peaked during the June to August dry season, coinciding with the rotavirus season. The bulk of the diarrheal disease burden occurred in children <1 year of age. Average medical costs for each child for the hospitalization were $44.22 ± $23.74 and the total economic burden per hospitalization was $101, of which 65% was borne by the household. The unit cost of introducing rotavirus vaccines 2012 was 22.69 US. Among the 397 stool samples that were genotyped, 5 G types (G1, G4, G8, G9, and G12) and 3 P types (P[4], P[6], and P[8]) were identified. G8 (30.3%), G9 (28.0%), and G1 (19.7%) were the most prevalent G types, while P[8] (52.0%) and P[4] (32.6%) were the most prevalent P types. There was a significant amount of mixed G genotypes (12.1%), while mixed P types were less common (5.1%). G8P[4], G9P[8], and G1P[8] were the most prevalent strains, accounting for 27.8%, 24.3%, and 15.3% of all specimens, respectively.Compared with the 2009–11 pre vaccine baseline, hospital admissions for non-bloody diarrhea captured by the HMIS fell by 17–29% from a pre-vaccine median of 4051 to 2881 in 2013 and 3371 in 2014, admissions for AGE captured in pediatric ward registries decreased by 48–49%, and admissions specific to rotavirus captured by active surveillance fell by 61–70%. The greatest effect was recorded in children age-eligible to be vaccinated, but we noted a decrease in the proportion of children with diarrhea testing positive for rotavirus in almost every age group.ConclusionGiven the stable and consistent trends and the prominent seasonality consistent with that of rotavirus, HMIS data should provide a useful baseline to monitor rotavirus vaccine impact on the overall diarrheal disease burden in Rwanda. Active, sentinel surveillance for rotavirus diarrhea will help interpret changes in diarrheal disease trends following vaccine introduction. Other countries planning rotavirus vaccine introduction should explore the availability and quality of their HMIS data.Households often bear the largest share of the economic burden attributable to diarrhea hospitalization and the burden can be substantial, especially for households in the lowest income quintile.The cost of introduction of new vaccines (rotavirus) is less than the cost of treating the diarrhea diseases. The number of admissions to hospital for diarrhea and rotavirus in Rwanda fell substantially after rotavirus vaccine implementation, including among older children age-ineligible for vaccination, suggesting indirect protection through reduced transmission of rotavirus. These data highlight the benefits of routine vaccination against rotavirus in low-income settings. / Doctorat en Santé Publique / info:eu-repo/semantics/nonPublished

In view of the recent implementation of a publicly funded rotavirus vaccination program in Ontario, we undertook studies to help guide the design of a safety evaluation of the vaccine with respect to intussusception. We used administrative data to develop and validate an algorithm for intussusception, and quantified its incidence in Ontario. We also conducted a systematic review of study designs used to evaluate post-licensure vaccine safety, and discussed each design’s strengths and weaknesses. The validated algorithm for intussusception was sensitive (89.3%) and highly specific (>99.9%). We observed the highest mean incidence (34 / 100,000) in males <1 year of age. While other designs are more robust, the inability to ascertain individual vaccination status from Ontario’s administrative data dictated our selection of an ecological design for safety evaluation of rotavirus vaccine. Data assimilated from this thesis represent a critical step toward the timely evaluation of rotavirus vaccine safety in Ontario.

In view of the recent implementation of a publicly funded rotavirus vaccination program in Ontario, we undertook studies to help guide the design of a safety evaluation of the vaccine with respect to intussusception. We used administrative data to develop and validate an algorithm for intussusception, and quantified its incidence in Ontario. We also conducted a systematic review of study designs used to evaluate post-licensure vaccine safety, and discussed each design’s strengths and weaknesses. The validated algorithm for intussusception was sensitive (89.3%) and highly specific (>99.9%). We observed the highest mean incidence (34 / 100,000) in males <1 year of age. While other designs are more robust, the inability to ascertain individual vaccination status from Ontario’s administrative data dictated our selection of an ecological design for safety evaluation of rotavirus vaccine. Data assimilated from this thesis represent a critical step toward the timely evaluation of rotavirus vaccine safety in Ontario.

No description available.

Submitted by Maria Creuza Silva (mariakreuza@yahoo.com.br) on 2014-10-03T17:40:16Z No. of bitstreams: 1 Tese Maria Yury Ichihara. 2014.pdf: 2248119 bytes, checksum: 821a02dd8be59ca78df05111c9fdd559 (MD5) / Approved for entry into archive by Maria Creuza Silva (mariakreuza@yahoo.com.br) on 2014-10-07T13:52:13Z (GMT) No. of bitstreams: 1 Tese Maria Yury Ichihara. 2014.pdf: 2248119 bytes, checksum: 821a02dd8be59ca78df05111c9fdd559 (MD5) / Made available in DSpace on 2014-10-07T13:52:13Z (GMT). No. of bitstreams: 1 Tese Maria Yury Ichihara. 2014.pdf: 2248119 bytes, checksum: 821a02dd8be59ca78df05111c9fdd559 (MD5) / A diarréia é uma das causas mais freqüentes de atendimentos ambulatoriais e de hospitalização em menores de 5 anos. Bactérias e o rotavírus são os principais agentes etiológicos envolvidos nas diarréias graves, sendo o rotavírus responsável por 22% a 38% das admissões hospitalares. Para abordar o tema sobre a internação de crianças brasileiras menores de 2 anos devido a diarréia foram realizados três estudos casos-controles com base hospitalar. Inicialmente, foi estimada a associação dos fatores de risco e a internação por diarréia aguda (exceto àquela causada por rotavírus) de acordo com as rotas de transmissão dos agentes etiológicos, as várias fontes de infecção e as condições de vida das populações. Foi demonstrado que os principais fatores de risco associados à internação por diarréia foram a falta de esgotamento sanitário e de água de boa qualidade e ter uma ou mais internações prévias devido à diarréia. Em relação à diarréia aguda causada por rotavírus, a OMS recomenda o uso de duas vacinas licenciadas no mundo (Rotarix® e RotaTeq®). A vacina oral monovalente contra rotavirus (G1P[8], Rotarix®) foi introduzida no Programa Nacional de Imunização do Brasil em 2006. A eficácia e efetividade da vacina variam entre países com renda alta e baixa, embora exista forte evidência de proteção cruzada para os genótipos G1-G4 e G9. Avaliamos a efetividade global e genótipo-específica da vacina oral monovalente na prevenção de internação de crianças brasileiras com diarréia causada por rotavirus. Além disso, estimamos a efetividade da vacina global e genótipo-específica por tempo de vacinação após a segunda dose da vacina (até dois anos) e EV para as Regiões brasileiras. Elevadas efetividades geral e genótipo-específica da vacina foram observadas, mesmo num contexto de grande diversidade genotípica e com predominância do genótipo G2P[4]. A duração da proteção global e genótipo-específica da vacina permaneceu até dois anos e foi maior para G1P[8] do que para G2P[4]. Por outro lado, consideramos plausível que a EV poderia variar em diferentes populações e em diferentes períodos de tempo, mediante a grande diversidade genotípica, a ocorrência de genótipos incomuns, de combinações mistas de G e P e de emergência de novas cepas advindas de combinações inter-espécies (homem e animal). Analisamos a EV estratificada por Regiões brasileiras e ficou demonstrado que a EV para a Região Norte foi similar à EV global. Porém a EV para as outras Regiões foi menor, talvez devido ao pequeno número de casos. Baseado nos resultados dos estudos nós recomendamos: 1) implementar ações voltadas para o domínio público (ambiente, saneamento, higiene na comunidade e acesso a serviços de saúde) para reduzir a morbidade por diarréia; 2) a continuidade do uso da vacina oral monovalente no Programa Nacional de Imunização; e 3) o monitoramento de genótipos para detecção precoce de cepas novas e incomuns. Além disso, novos estudos precisam ser conduzidos para avaliar variações da efetividade da vacina entre as Regiões, as sub-regiões e as áreas mais vulneráveis do Brasil. Será importante realizar estudos de custo-efetividade para subsidiar a política nacional de imunização. / Diarrhea has been a frequent reason of visits to the health services and hospitalization among children under five. Bacteria and rotavirus are the main agents involved in severe diarrhea, in which rotavirus is responsible from 22% to 38% of children hospital admissions. To address the issue of hospitalization of Brazilian children under 2 years due to diarrhea, we conducted three hospital based case-control study. Initially, we aimed to estimate the association of risk factors and acute diarrhea hospitalization (except those caused by rotavirus) according to the routes of transmission of etiologic agents, the various sources of infection and the living conditions of populations. It was demonstrated that the main risk factors were lack of sewage and water of good quality, and already having one or more hospitalizations due to diarrhea. In relation to the rotavirus acute diarrhea, the World Health Organization has been recommended the use of two licensed vaccines worldwide (Rotarix ® and RotaTeq ®). The oral monovalent rotavirus vaccine (G1[P8] strain, Rotarix®) was introduced in Brazilian National Immunization Program in 2006. The vaccine efficacy and effectiveness vary between high and low income countries, although there is strong evidence of cross-protection for G1-G4 and G9 genotypes. We evaluated overall and genotype-specific oral monovalent rotavirus VE in preventing RV-A diarrhea hospital admission of Brazilian children. Also, we estimated overall and genotype-specific VE by time since second dose vaccination (up to two years) and VE according to Brazilian Regions. High overall and genotype-specific VE were observed, even though there was a great diversity of rotavirus genotypes circulating in Brazil and a predominance of G2P[4] genotype. The overall and genotype-specific VE lasted for two years after second dose vaccination and it was higher for G1P[8] than G2P[4]. Besides, we considered that it was plausible that RV-A VE could vary in different populations (Regions) and in different periods of time, since there was a great genotype diversity, an occurrence of unusual genotypes, mixed combinations of G and P and emergence of new strains from combinations of inter-species (human and animal). We analyzed the VE for Brazilian Regions and we demonstrated that the VE for Northern Region was similar to the overall VE. However, the VE for other Regions was lower than VE for Northern Region, maybe because of the small number of the cases. Based on the findings of the studies we recommend: 1) to implement actions of the public domain (environment, sanitation, hygiene in the community and access to health services) to reduce the diarrhea morbidity; 2) the continued use of oral monovalent rotavirus vaccine in the National Immunization Program; and 3) the monitoring for early detection of unusual and novel rotavirus genotypes. In addition, new studies should be conducted to evaluate the variations of rotavirus VE in different Regions, sub-Regions and vulnerable areas in Brazil. It might be useful to conduct cost-effectiveness studies to inform national immunization policy.

Os norovírus (NV) são uma importante causa de hospitalização infantil. Crianças internadas por gastroenterite por NV (GENV) são consideradas portadoras de diarreia grave. O objetivo desse estudo, realizado na cidade do Rio de Janeiro, Brasil, é descrever as características clínicas e a frequência da diarreia por NV em crianças hospitalizadas, comparando as taxas de detecção de NV em crianças vacinadas e não vacinadas contra rotavírus (Rotarix). Foram coletadas 659 amostras de fezes de igual número de crianças e encaminhadas para análise pela reação em cadeia pela polimerase, precedida de transcrição reversa no período de janeiro de 2004 a dezembro de 2009. O percentual de amostras positivas para os NV foi de 27,3% nesse período. Das 180 amostras positivas para NV, 55% tiveram origem na comunidade (aqCo) e 45% foram de aquisição nosocomial (aqNo). O percentual de GENV nos dois anos anteriores (2004 e 2005) à introdução da vacina Rotarix foi de 28,3%, sendo 11,3% o percentual de amostras aqCo. Nos dois anos posteriores (2008 e 2009), a GENV significou 24,4%, e as amostras aqCo foram 14,9% (p<0,05). Em 647 crianças, 494 não receberam a vacina Rotarix, enquanto 151 crianças receberam, pelo menos, uma dose. O percentual de GENV foi de 23,8% e 39,7%, respectivamente (p<0,05). Apesar do comportamento sazonal dos casos de GENV aqCo, esse fato não teve significância estatística. Das 180 crianças, 61,6% tinham peso &#8804; p10 do NCHS, 82,2% tinham idade &#8804; 5anos. As crianças com idade &#8804; 2 anos foram mais acometidas nos casos de aqCo do que àquelas de aqNo (p<0,05). Foram observados em 82 crianças: vômitos (73,2%), febre (54,9%), tosse (20,7%), coriza (2,2%), sangue nas fezes (8,5%), erupção cutânea (4,9%) e broncoespasmo (7,3%). Houve significância estatística com relação à frequência maior de febre, coriza, tosse e broncoespasmo nas crianças com GENV de aqCo do que naquelas de aqNo (p<0,05). De 69 crianças, 73,9% apresentaram desidratação e, dessas, 76,5% necessitaram de hidratação venosa. Esses dados tiveram significância estatística, representada por maiores percentuais nas crianças com GENV de aqCo do que naquelas de aqNo (p<0,05). Esse estudo demonstra que os NV foram um importante agente etiológico nos casos de gastroenterites em crianças hospitalizadas e responsável por altas taxas de infecções nosocomiais. Estatisticamente, não foi comprovada uma tendência de aumento dos casos de GENV no período do estudo, como também do aumento da frequência de GENV nos anos posteriores em relação aos anos anteriores à introdução da vacina Rotarix no Brasil em 2006. No entanto, houve significância estatística quando foi avaliado o percentual de GENV em crianças hospitalizadas vacinadas e não vacinadas contra RV. Um aumento dos casos de GENV em crianças poderá vir a acontecer nos próximos anos, quando é esperado que um número maior de crianças será vacinado contra RV. Tosse, coriza e broncoespasmo são sintomas que devem ser mais detalhadamente investigados. Estratégias de prevenção contra a disseminação dos NV são condutas importantes em unidades de internação. Uma vacina eficaz contra norovírus pode ser um benefício significativo para reduzir o percentual de crianças hospitalizadas por diarreia. / Noroviruses (NV) are a major cause of infant hospitalization. Children hospitalized for gastroenteritis NV (NVGE) are considered to have severe diarrhea. The purpose of this study, conducted in the city of Rio de Janeiro, Brazil, is to describe the clinical characteristics and frequency of norovirus diarrhea in hospitalized children, comparing the rates of detection of NV in vaccinated and unvaccinated children against rotavirus (RV). We collected 659 fecal samples from equal numbers of children and sent for analysis by polymerase chain reaction, reverse transcription from January 2004 to December 2009. The percentage of samples positive for NV was 27.3% in this period. Of the 180 samples positive for NV, 55% meant source community (Coaq) and 45% of nosocomial acquisition (Noaq). The percentage of NVGE the previous two years (2004 and 2005) the introduction of the vaccine against RV was 28.3% and 11.3% represented the percentage of samples Coaq. In the two subsequent years (2008 and 2009), NVGE meant to 24.4%, and the samples were Coaq 14.9% (p <0.05). In 647 children, 494 received no vaccine against RV while 151 children received at least one dose. The percentage of NVGE was 23.8% and 39.7%, respectively (p <0.05). Despite the seasonal behavior of NVGE aqCo cases, this did not reach statistical significance. Of the 180 children, 61.6% had weight &#8804; p10 NCHS, 82.2% were aged &#8804; 5 years old. Children aged &#8804; 2 years were most affected in cases of Coaq than those of Noaq (p <0.05). Were observed in 82 children: vomiting (73.2%), fever (54.9%), cough (20.7%), coryza (2.2%), blood in stools (8.5%), rash (4.9%) and bronchospasm (7.3%). There was statistical significance with respect to the higher frequency of fever, coryza, coughing and wheezing in children with NVGE of Coaq than those of Noaq (p <0.05). Of 69 children, 73.9% had dehydration and of these, 76.5% required intravenous hydration. These data were statistically significant, represented by the highest percentage of children with NVGE of Coaq than those of Noaq (p <0.05). This study demonstrates that the NV were an important etiologic agent in cases of gastroenteritis in hospitalized children and responsible for high rates of nosocomial infections. Statistically, , it was not shown a tendency to increase in cases of NVGE during the study period, as well as the increased frequency NVGE in later years relative to years prior to the introduction of RV vaccine in Brazil. However, statistical significance was assessed as the percentage of NVGE in hospitalized children vaccinated and unvaccinated against RV. An increase in cases of children in NVGE could happen in the next few years, when it is expected that a greater number of children will be vaccinated against RV. Cough, coryza and wheezing are symptoms that should be further investigated. Strategies for preventing the spread of NV are important conduits in inpatient units. An effective vaccine against norovirus can be a significant benefit to reduce the percentage of children hospitalized for diarrhea.

Os norovírus (NV) são uma importante causa de hospitalização infantil. Crianças internadas por gastroenterite por NV (GENV) são consideradas portadoras de diarreia grave. O objetivo desse estudo, realizado na cidade do Rio de Janeiro, Brasil, é descrever as características clínicas e a frequência da diarreia por NV em crianças hospitalizadas, comparando as taxas de detecção de NV em crianças vacinadas e não vacinadas contra rotavírus (Rotarix). Foram coletadas 659 amostras de fezes de igual número de crianças e encaminhadas para análise pela reação em cadeia pela polimerase, precedida de transcrição reversa no período de janeiro de 2004 a dezembro de 2009. O percentual de amostras positivas para os NV foi de 27,3% nesse período. Das 180 amostras positivas para NV, 55% tiveram origem na comunidade (aqCo) e 45% foram de aquisição nosocomial (aqNo). O percentual de GENV nos dois anos anteriores (2004 e 2005) à introdução da vacina Rotarix foi de 28,3%, sendo 11,3% o percentual de amostras aqCo. Nos dois anos posteriores (2008 e 2009), a GENV significou 24,4%, e as amostras aqCo foram 14,9% (p<0,05). Em 647 crianças, 494 não receberam a vacina Rotarix, enquanto 151 crianças receberam, pelo menos, uma dose. O percentual de GENV foi de 23,8% e 39,7%, respectivamente (p<0,05). Apesar do comportamento sazonal dos casos de GENV aqCo, esse fato não teve significância estatística. Das 180 crianças, 61,6% tinham peso &#8804; p10 do NCHS, 82,2% tinham idade &#8804; 5anos. As crianças com idade &#8804; 2 anos foram mais acometidas nos casos de aqCo do que àquelas de aqNo (p<0,05). Foram observados em 82 crianças: vômitos (73,2%), febre (54,9%), tosse (20,7%), coriza (2,2%), sangue nas fezes (8,5%), erupção cutânea (4,9%) e broncoespasmo (7,3%). Houve significância estatística com relação à frequência maior de febre, coriza, tosse e broncoespasmo nas crianças com GENV de aqCo do que naquelas de aqNo (p<0,05). De 69 crianças, 73,9% apresentaram desidratação e, dessas, 76,5% necessitaram de hidratação venosa. Esses dados tiveram significância estatística, representada por maiores percentuais nas crianças com GENV de aqCo do que naquelas de aqNo (p<0,05). Esse estudo demonstra que os NV foram um importante agente etiológico nos casos de gastroenterites em crianças hospitalizadas e responsável por altas taxas de infecções nosocomiais. Estatisticamente, não foi comprovada uma tendência de aumento dos casos de GENV no período do estudo, como também do aumento da frequência de GENV nos anos posteriores em relação aos anos anteriores à introdução da vacina Rotarix no Brasil em 2006. No entanto, houve significância estatística quando foi avaliado o percentual de GENV em crianças hospitalizadas vacinadas e não vacinadas contra RV. Um aumento dos casos de GENV em crianças poderá vir a acontecer nos próximos anos, quando é esperado que um número maior de crianças será vacinado contra RV. Tosse, coriza e broncoespasmo são sintomas que devem ser mais detalhadamente investigados. Estratégias de prevenção contra a disseminação dos NV são condutas importantes em unidades de internação. Uma vacina eficaz contra norovírus pode ser um benefício significativo para reduzir o percentual de crianças hospitalizadas por diarreia. / Noroviruses (NV) are a major cause of infant hospitalization. Children hospitalized for gastroenteritis NV (NVGE) are considered to have severe diarrhea. The purpose of this study, conducted in the city of Rio de Janeiro, Brazil, is to describe the clinical characteristics and frequency of norovirus diarrhea in hospitalized children, comparing the rates of detection of NV in vaccinated and unvaccinated children against rotavirus (RV). We collected 659 fecal samples from equal numbers of children and sent for analysis by polymerase chain reaction, reverse transcription from January 2004 to December 2009. The percentage of samples positive for NV was 27.3% in this period. Of the 180 samples positive for NV, 55% meant source community (Coaq) and 45% of nosocomial acquisition (Noaq). The percentage of NVGE the previous two years (2004 and 2005) the introduction of the vaccine against RV was 28.3% and 11.3% represented the percentage of samples Coaq. In the two subsequent years (2008 and 2009), NVGE meant to 24.4%, and the samples were Coaq 14.9% (p <0.05). In 647 children, 494 received no vaccine against RV while 151 children received at least one dose. The percentage of NVGE was 23.8% and 39.7%, respectively (p <0.05). Despite the seasonal behavior of NVGE aqCo cases, this did not reach statistical significance. Of the 180 children, 61.6% had weight &#8804; p10 NCHS, 82.2% were aged &#8804; 5 years old. Children aged &#8804; 2 years were most affected in cases of Coaq than those of Noaq (p <0.05). Were observed in 82 children: vomiting (73.2%), fever (54.9%), cough (20.7%), coryza (2.2%), blood in stools (8.5%), rash (4.9%) and bronchospasm (7.3%). There was statistical significance with respect to the higher frequency of fever, coryza, coughing and wheezing in children with NVGE of Coaq than those of Noaq (p <0.05). Of 69 children, 73.9% had dehydration and of these, 76.5% required intravenous hydration. These data were statistically significant, represented by the highest percentage of children with NVGE of Coaq than those of Noaq (p <0.05). This study demonstrates that the NV were an important etiologic agent in cases of gastroenteritis in hospitalized children and responsible for high rates of nosocomial infections. Statistically, , it was not shown a tendency to increase in cases of NVGE during the study period, as well as the increased frequency NVGE in later years relative to years prior to the introduction of RV vaccine in Brazil. However, statistical significance was assessed as the percentage of NVGE in hospitalized children vaccinated and unvaccinated against RV. An increase in cases of children in NVGE could happen in the next few years, when it is expected that a greater number of children will be vaccinated against RV. Cough, coryza and wheezing are symptoms that should be further investigated. Strategies for preventing the spread of NV are important conduits in inpatient units. An effective vaccine against norovirus can be a significant benefit to reduce the percentage of children hospitalized for diarrhea.