RESUMO
OBJECTIVE: To study the epidemiology and strain variations of astrovirus infection among children under 5 years of age, hospitalized for acute diarrhea in China. METHODS: Inpatients under 5 years of age with acute diarrhea in hospitals of seven provinces between 1998 and 2005 were enrolled in the study Stool specimens were collected and tested for astrovirus using the Dako Amplified IDEIA Astrovirus kits or reverse-transcription polymerase chain reaction (RT-PCR). Genetic identities of the strains were determined using RT-PCR with serotype-specific primers and confirmed by sequencing of the RT-PCR products. RESULTS: A total of 1668 diarrheal stool samples tested for both rotavirus and calicivirus negative were examined. The detection rate of astrovirus infection was 5.5% (91/1668) and the diarrhea cases caused by astrovirus infection could be found in any season of the year but mainly occurred in cold season from October to next January. Astrovirus detection-rates were: 7.4% among infants aged 9-11 months followed by 6.1% in 12-17 month-olds, and 6-8 months 5.6% & 0-2 months 5.6% before 8 months. Over 95% of astrovirus infections occurred in children before 2 years of age. Among 49 strains, typed, serotype 1(45/91) was most commonly seen while serotype 5 was in two cases and serotype 3 and 8 were detected in only one case respectively. CONCLUSION: Astrovirus seemed an important etiologic agent in young children with acute diarrhea in China and Serotype 1 was the most prevalent one.
Assuntos
Infecções por Astroviridae/epidemiologia , Astroviridae/classificação , Diarreia/virologia , Doença Aguda , Astroviridae/isolamento & purificação , Infecções por Astroviridae/complicações , Pré-Escolar , China/epidemiologia , DNA Viral/análise , Humanos , Lactente , Recém-Nascido , Pacientes Internados , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estações do Ano , SorotipagemRESUMO
<p><b>OBJECTIVE</b>To provide information on epidemiology of rotavirus infection in Beijing, China.</p><p><b>METHODS</b>An ongoing hospital-based surveillance was conducted among children < 5yr old with acute diarrhea according to WHO generic protocol (CID-98). During a 3-year study (Apr. 1998 to Mar. 2001), a total of 484 stool samples were collected from 1 457 patients, including 275 samples from 1 048 outpatients and 209 samples from 409 inpatients.</p><p><b>RESULTS</b>The overall detection rate of rotavirus infection was 25.4%. Rotavirus was responsible for 27.3% of diarrhea inpatients on a yearly base, and 46.2% during rotavirus season. Two peaks of diarrhea were observed each year, one in the summer (June-Sep.) due to bacterial dysentery (16.7%) and another in fall winter (Oct.-Dec.) due to rotavirus infection (23.0%). The detection rate on rotavirus was the highest in age group of 6 - 11 months (38.2%), followed by 1 - 2 years old (28.5%). Ninety six point eight percentage of children were infected under 3 years of age. The number of deaths, possibly caused by rotavirus diarrhea were accounted for 40% of all diarrhea deaths and 11.1% of the total deaths. Serotyping of 123 rotavirus isolates showed that serotype G1 (55.3%) was predominant, followed by G2 (26.8%), G3 (9.8%), G4 (0.8%), and 10 isolates (8.1%) remained non-typeable. Mixed infections (0.8%) seemed to be rare.</p><p><b>CONCLUSION</b>Rotavirus diarrhea was an important infectious disease among children in Beijing. Safe and effective rotavirus vaccines for the prevention of severe diarrheas and the reduction of treatment costs are of significant importance to China.</p>
Assuntos
Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Fatores Etários , China , Epidemiologia , Disenteria , Epidemiologia , Hospitais , Vigilância da População , Rotavirus , Classificação , Infecções por Rotavirus , Epidemiologia , SorotipagemRESUMO
<p><b>OBJECTIVE</b>To establish baseline patterns of rotavirus diarrhea and to describe its epidemiologic features in Changchun city, prior to rotavirus vaccine immunization.</p><p><b>METHODS</b>Hospital-based surveillance was conducted among children under 5 years old with acute diarrhea in Changchun Children's Hospital. Fecal samples were determined to identify rotavirus by PAGE and/or ELISA. G serotypes of rotavirus were identified by ELISA and/or nested RT-PCR. P genotyping were carried out by RT-PCR. All data were computerized and analysed by "Generic Manual on Rotavirus Surveillance" set by CDC in the USA.</p><p><b>RESULTS</b>In total, 2 343 diarrhea cases were screened and 1 211 fecal samples were collected. Rotavirus was detected in 31.0% among outpatients and 52.9% in inpatients. During the peak of the season (November through March), 58.6% of diarrhea was caused by rotavirus among inpatients. 95.0% of rotavirus diarrhea cases occurred among children aged < 2 years. The predominant strain was serotype G1 (82.4%), followed by G2 (5.0%), G3 (3.3%), G4 (0.9%). P genotyping showed that P[8] and P[4] were the most common ones. Nine different P-G combinations were identified, four strains (P[8]G1, P[4]G2, P[8]G3, and P[8]G4) commonly seen worldwide accounted for 75.6% of the total. Taken together with uncommon strains, including the novel types P[4]G4 and P[8]G2, it highlights the extraordinary diversity of rotaviruses circulating in China.</p><p><b>CONCLUSION</b>Rotavirus is the major cause of severe child diarrhea in Changchun. Developing a rotavirus vaccine for prevention of severe disease and reduction of treatment costs seemed to be necessary.</p>