Características clínicas e frequência de diarreia por norovírus em crianças hospitalizadas, vacinadas e não vacinadas contra rotavírus Rio de Janeiro, Brasil, 2004-2009

Abstract

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 ≤ p10 NCHS, 82.2% were aged ≤ 5 years old. Children aged ≤ 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.