[Distribution signature analysis between intussusception and rotavirus diarrhea in young children].

OBJECTIVE: To investigate the annual incidence rate of intussusception over a 5-year period in Suzhou and to determine whether there was a potential link between intussusception rotavirus diarrhea. METHODS: Outpatient and inpatient data from 1999 through 2003 retrospectively were reviewed for young children (< 2 year old) whose diagnosis was confirmed by ultrasonography or radiography and patients were reduced by air enema or surgery. From September 2001, to August 2003, inpatients with diarrhea (< 2 year old) were detected rotavirus antigen in the stool by ELISA technology. RESULTS: From 1999 through 2003, 1101 cases were reported in children below 2 years old. The incidence rate of intussusception under 1 year age each year was 275.3, 338.2, 547.0, 515.3, and 425.4 per 100,000 child years respectively (the average annual incidence was 418.1 per 100,000 child years), and the incidence of intussusception increased over time from 1999 to 2003. A peak age distribution of intussusception was infants 4 to 10 months old (692/1101, 62.85%) and mean age was 9.62 +/- 5.65 months, which were greatly different from those of patients with rotavirus diarrhea, whose peak age distribution was 5 to 16 months old (252/331, 76.13%), and mean age was 11.42 +/- 5.14 months (Z = 6.90, P < 0.01). The peak month distribution of intussusception was from April to August (595/1101, 54.04%), which was distinct from that of patient with rotavirus diarrhea, whose peak month distribution was between October and January (232/331, 70.09%). Test: chi2 = 226.06, P < 0.001. CONCLUSION: The annual incidence rate of intussusception for < 1 year of age was 418.1 per 100,000 child years in Suzhou. We found no epidemiologic evidence for an association between intussusception and rotavirus diarrhea.

[Epidemiological study on rotavirus-borne diarrhea in infants and children in different areas].

OBJECTIVE: To analyze and compare the epidemiological features of rotavirus diarrhea among infants in the different areas so as to provide data for rotavirus vaccine research. METHODS: From Sep. 2001 through Sep. 2003, sentinel sites were set up in Suzhou Children's Hospital and Maanshan Hospital. Fecal samples from children (< 5 years) with acute diarrheal were collected and enzyme linked immunosorbent assay was used to detect rotavirus antigen. Reverse transcription-polymerase chain reaction was used to determine the G serotypes and P genotypes of rotavirus strains. The features of strains in the two places and other areas of China were analyzed and compared. RESULTS: (1) Rotavirus infection appeared in autumn and winter, but the peaks varied. In Suzhou the peaks were from December to next February in 2001, and November to next January in 2002. But in Maanshan, it was November to next January for both two years. (2) Rate of rotavirus infection in Suzhou was much higher than that in Maanshan, infective rates of Inpatient Department and Outpatient Department are 47.28%, 28.39% and 30.38%, 14.77% respectively in the two hospitals. (3) Rates of infection in two hospitals showed age difference but the highest group was in 6 - 35 month-olds. No gender difference was found. (4) Secular distribution of G-typing and P-typing of rotavirus strain was different in Suzhou and Maanshan. G3 was mainly found in Suzhou and G1 in Maanshan. From 2002-2003 on, G3 became dominant in Maanshan. CONCLUSION: Rotavirus caused diarrhea among infant and children were different in terms of areas, period and types, suggesting that the introduction of rotavirus vaccine should be adjusted according to different strains with specific types and optimal timeline.