<b>OBJECTIVEb>To provide information on epidemiology of rotavirus infection in Beijing, China.

<b>METHODSb>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.

<b>RESULTSb>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.

<b>CONCLUSIONb>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.

Age Factors ; Child, Preschool ; China ; epidemiology ; Dysentery ; epidemiology ; etiology ; Female ; Hospitals ; statistics & numerical data ; Humans ; Infant ; Male ; Population Surveillance ; Rotavirus ; classification ; isolation & purification ; Rotavirus Infections ; complications ; epidemiology ; Serotyping

<b>OBJECTIVEb>To establish baseline patterns of rotavirus diarrhea and to describe its epidemiologic features in Changchun city, prior to rotavirus vaccine immunization.

<b>METHODSb>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.

<b>RESULTSb>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.

<b>CONCLUSIONb>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.

Child, Preschool ; China ; epidemiology ; Diarrhea ; etiology ; Electrophoresis, Polyacrylamide Gel ; Enzyme-Linked Immunosorbent Assay ; Feces ; virology ; Female ; Genotype ; Hospitals, Pediatric ; statistics & numerical data ; Humans ; Infant ; Male ; Reverse Transcriptase Polymerase Chain Reaction ; Rotavirus ; classification ; genetics ; isolation & purification ; Rotavirus Infections ; complications ; epidemiology ; virology ; Sentinel Surveillance ; Serotyping

<b>OBJECTIVEb>To study the epidemiological status on rotavirus diarrhea in Kunming to improve the rotavirus vaccine immunization program.

<b>METHODSb>A hospital-based sentinel surveillance program for rotavirus was set up among children less than 5 years old with acute diarrhea in Kunming Children's Hospital. Clinical information and fecal specimens were collected and rotavirus were detected by polyacrylamide gel electrophoresis (PAGE) and/or enzyme linked immunosorbent assay (ELISA). Positive specimens were further serotyped or genotyped by ELISA and/or RT-PCR.

<b>RESULTSb>During the three years of surveillance, 466 specimens were collected. Rotavirus were detected on 246 (52.8%) specimens. 97% of the rotavirus diarrhea cases occurred among children less than 2 years old. There was a peak of admissions for rotavirus diarrhea cases between October and December which accounted for 48% of all the rotavirus hospitalizations each year. Among 204 specimens with G serotyping, the predominant strain was serotype G1 (47.5%) followed by G2 (17.6%), G3 (15.7%), G9 (4.9%) and G4 (1.0%). Mixed infection (2.5%) were rare and 22 specimens (10.8%) remained non-typeable. P genotyping showed P[4], P[8] and P[6] were the most common strains, accounting for 29.3%, 27.6% and 13.8% respectively. P[4]G2 was the most common strain which accounted for 34.1% (14/41) followed by P[8]G1 (29.3%) and P[6]G9 (12.2%). Another 7 uncommon P-G combinations were also identified.

<b>CONCLUSIONb>Rotavirus was the major cause of acute diarrhea in Kunming. An effective rotavirus vaccine for prevention and control of rotavirus diarrhea should be developed.

Child, Preschool ; China ; epidemiology ; Diarrhea ; virology ; Electrophoresis, Polyacrylamide Gel ; Enzyme-Linked Immunosorbent Assay ; Female ; Genotype ; Hospitals, Pediatric ; statistics & numerical data ; Humans ; Infant ; Male ; Reverse Transcriptase Polymerase Chain Reaction ; Rotavirus ; classification ; genetics ; isolation & purification ; Rotavirus Infections ; epidemiology ; Sentinel Surveillance ; Serotyping