Investigação de patógenos virais associados à gastrenterite infantil aguda

A gastrenterite de etiologia viral está associada com altas taxas de morbidade, no mundo, sendo nos países em desenvolvimento, responsável também, por altos índices de mortalidade infantil. Este trabalho objetiva detectar a presença de rotavírus, adenovírus e astrovírus em casos de doença diarréica, acompanhar a dinâmica populacional dos rotavírus e avaliar a prevalência e a sazonalidade dessas infecções. A detecção de rotavírus e adenovírus foi realizada através da técnica de ensaio imunoenzimático (EIE). As amostras de rotavírus foram submetidas à eletroforese em gel de poliacrilamida (PAGE) para avaliação dos perfis eletroforéticos e acompanhamento da dinâmica populacional. A detecção de astrovírus foi realizada através da reação em cadeia da polimerase (RT-PCR). Das 338 amostras fecais testadas para rotavírus, foram detectadas 61 positivas (18,04%). A análise eletroforética mostrou a circulação de amostras com perfis característicos de rotavírus do grupo A, todos longos em 2005 e longos e curtos, com predominância dos últimos, em 2006. Das 316 amostras testadas para a presença de adenovírus e das 131 testadas para astrovírus, foram detectadas 17 (5,38%) e 2 (1,53%), respectivamente. Os resultados demonstram a participação destes vírus em casos de gastrenterite infantil e apontam para a importância da continuidade deste estudo

1998-1999 Rotavirus Seasons in Juiz de Fora, Minas Gerais, Brazil: Detection of an Unusual G3P[4] Epidemic Strain

An epidemiologic survey on the rotavirus strains causing gastroenteritis in young children was conducted in Juiz de Fora, Minas Gerais, in Southern Brazil during two consecutive seasons. Rotavirus was detected in 94 of the 1,056 fecal specimens collected from January 1998 to December 1999. Among the 13 discernible long electrophoretic profiles found, one was highly prevalent (73.4%) and represented the rotavirus strain responsible for the May-August winter epidemic outbreak of 1998, as clearly shown in a three-dimensional graph. This epidemic strain, designated JF98, was characterized as subgroup II and genotype G3P[4] by the original reverse transcription-PCR typing assays. Besides the unusual combination of G and P types, this G3 strain lacked reactivity with anti-G3-specific monoclonal antibodies and presented an uncommon pattern upon digestion of its cDNA-copied VP7 gene with the BstYI restriction enzyme. Strain JF98 affected primarily 6- to 24-month-old children and accounted for 85.5% of the severe rotavirus-associated dehydrating diarrhea cases that required hospitalization. As in our previous studies in neighboring Rio de Janeiro and São Paulo, a remarkably large proportion (44%) of mixed infections was detected, generating a complex set of circulating strains in the community, represented by the many distinct electropherotypes. Other common human types were detected as minor strains in single or in mixed infections, including the JF98 strain. Those were types G1, G4, G8, G9, P[8], and P[6], but not G2 or G5. One specimen contained a mixture of group A and C rotaviruses

Epidemiological aspects of rotavirus infections in Minas Gerais, Brazil

In order to develop good polices regarding public health measures and vaccine use to prevent rotavirus induced gastroenteritis, the epidemiology of the illness in various regions of Brazil is necessary. Accordingly, this study was to detect the frequency and types of rotavirus in one city in a tropical part of Brazil. This is an epidemiological survey of pediatric gastroenteritis caused by rotavirus conducted in Juiz de Fora, Minas Gerais State, Brazil. We analyzed 656 in-patient (190) and out-patient (466) stool samples from children ages 0 to 5 years during 1998. Rotavirus detection was performed using polyacrylamide gel electrophoresis (PAGE). Rotavirus was isolated from 62/190 stool samples (32.6%) from hospitalized children and 16/466 (3.4%) from out-patients. The overall rotavirus frequency in this population was 11.9%. The highest rotavirus detection was found in hospitalized children ages 6 to 24 months. Rotaviruses were detected from March to September, with a peak incidence in June (33.3%), the coldest and driest month in the region. Electrophoretic analysis identified 10 different profiles, all long and compatible with group A rotavirus, termed L A through LJ. The L B and L D profiles circulated throughout most of the study period. However, in June, when the highest detection rate occurred, the vast majority (92.5%) of the positive samples displayed the L B profile, thus suggesting an outbreak caused by this rotavirus profile. Rotavirus induced gastroenteritis is common in one tropical region of Brazil, it is an important cause of diarrhea in hospitalized children ages 6 to 24 months, it is most common during dry, cold months of the year, and it may occur in electrophoretype restricted epidemics. Such analyses throughout Brazil will assist in developing sound guidelines regarding its prevention

Epidemiological aspects of rotavirus infections in Minas Gerais, Brazil

In order to develop good polices regarding public health measures and vaccine use to prevent rotavirus induced gastroenteritis, the epidemiology of the illness in various regions of Brazil is necessary. Accordingly, this study was to detect the frequency and types of rotavirus in one city in a tropical part of Brazil. This is an epidemiological survey of pediatric gastroenteritis caused by rotavirus conducted in Juiz de Fora, Minas Gerais State, Brazil. We analyzed 656 in-patient (190) and out-patient (466) stool samples from children ages 0 to 5 years during 1998. Rotavirus detection was performed using polyacrylamide gel electrophoresis (PAGE). Rotavirus was isolated from 62/190 stool samples (32.6%) from hospitalized children and 16/466 (3.4%) from out-patients. The overall rotavirus frequency in this population was 11.9%. The highest rotavirus detection was found in hospitalized children ages 6 to 24 months. Rotaviruses were detected from March to September, with a peak incidence in June (33.3%), the coldest and driest month in the region. Electrophoretic analysis identified 10 different profiles, all long and compatible with group A rotavirus, termed L A through LJ. The L B and L D profiles circulated throughout most of the study period. However, in June, when the highest detection rate occurred, the vast majority (92.5%) of the positive samples displayed the L B profile, thus suggesting an outbreak caused by this rotavirus profile. Rotavirus induced gastroenteritis is common in one tropical region of Brazil, it is an important cause of diarrhea in hospitalized children ages 6 to 24 months, it is most common during dry, cold months of the year, and it may occur in electrophoretype restricted epidemics. Such analyses throughout Brazil will assist in developing sound guidelines regarding its prevention

Acute diarrhea in hospitalized children of the municipality of juiz de fora, MG, Brazil: prevalence and risk factors associated with disease severity

CONTEXT: Acute diarrhea is a common cause of hospitalization among children under 5 years of age. Knowing the prevalence and risk factors associated with the severity of acute diarrhea is essential to control morbidity and mortality. OBJECTIVE: Describe the prevalence of demographic, epidemiologic and clinical features of children under 6 years of age hospitalized for acute diarrhea, and investigate the association between these determinants and the severity of the diarrheic episode. METHOD: Retrospective, cross-sectional study, during the period from January, 2005 through December, 2008, in the municipality of Juiz de Fora, MG, Brazil. Files from 6,201 children from 0 to 6 years of age, hospitalized in two public teaching institutions (which account for 84% of all the hospitalizations in the municipality), were assessed. Acute diarrhea was defined as the presence of at least three evacuations of liquid or loose stools, within 24 hours, for a maximum period of 14 days. The patients with acute diarrhea were divided in two groups, according to disease severity, severe diarrhea being considered whenever hospitalization lasted for at least 4 days. Epidemiologic and clinical data were assessed and compared through the application of the chi-squared test and the binomial logistic regression model. RESULTS: The prevalence rate for admission due to acute diarrhea was 8.4%. The factors significantly associated with the severity of the diarrheic episode were: age under 6 months (P = 0.01, OR = 2.762); disease onset during fall (P = 0.033, OR = 1.742), presence of fever (P = 0.017, OR = 1.715) and antibiotic use during hospitalization (P = 0.000, OR = 3.872). CONCLUSIONS: Diarrhea is the third most common cause of hospitalization among children under 6 years of age in Juiz de Fora. Young age (under or equal to 6 months), fever, antibiotic use during hospitalization and disease onset during fall are risk factors associated with longer hospital stay

The role of human adenoviruses type 41 in acute diarrheal disease in Minas Gerais after rotavirus vaccination

Abstract Human adenovirus species F (HAdV-F) type 40 and 41 are commonly associated with acute diarrheal disease (ADD) across the world. Despite being the largest state in southeastern Brazil and having the second largest number of inhabitants, there is no information in the State of Minas Gerais regarding the role of HAdV-F in the etiology of ADD. This study was performed to determine the prevalence, to verify the epidemiological aspects of infection, and to characterize the strains of human adenoviruses (HAdV) detected. A total of 377 diarrheal fecal samples were obtained between January 2007 and August 2011 from inpatient and outpatient children of age ranging from 0 to 12 years. All samples were previously tested for rotavirus, norovirus, and astrovirus, and 314 of 377 were negative. The viral DNA was extracted, amplified using the polymerase chain reaction and the HAdV-positive samples were sequenced and phylogenetically analyzed. Statistical analyses were performed using the Chi-square test (p < 0.05), considering two conditions: the total of samples tested (377) and the total of negative samples for the remaining viruses tested (314). The overall prevalence of HAdV was 12.47% (47/377); and in 76.60% (36/47) of the positive samples, this virus was the only infectious agent detected. The phylogenetic analysis of partial sequences of 32 positive samples revealed that they all clustered with the HAdV-F type 41. The statistical analysis showed that there was no correlation between the onset of the HAdV infection and the origin of the samples (inpatients or outpatients) in the two conditions tested: the total of samples tested (p = 0.598) and the total of negative samples for the remaining viruses tested (p = 0.614). There was a significant association in the occurrence of infection in children aged 0&#8211;12 months for the condition 1 (p = 0.030) as well as condition 2 (p = 0.019). The occurrence of infections due to HAdV did not coincide with a pattern of seasonal distribution. These data indicate the significant involvement of HAdV-F type 41 in the etiology of ADD in Minas Gerais, which demonstrates the importance of other viral agents in the development of the disease after the introduction of rotavirus vaccine immunization