Viral diarrhea in children in Beijing, China.

A study was undertaken from November 1994 to August 1996 to determine the role of viruses in children (< or =5 years of age) hospitalized at Beijing Children Hospital, Beijing China, for acute diarrhea. Stool samples from diarrheal patients were investigated by ELISA, electron microscopy, and RT-PCR for the presence of rotavirus, calicivirus, astrovirus, and adenovirus. Group A rotavirus was detected in 55.9% of all diarrheal patients and comprised 82.5% of all viruses detected. Group A rotavirus samples were further characterized for their G-type specificity by RT-PCR. Four major G types (1-4) were identified. G1 to G4 accounted for 58.9%, 15.7%, 16.8%, and 6.3%, respectively, of the serotyped samples. Almost all rotavirus infections occurred in children less than 1 year of age, with a significant clustering during the winter months. Group C rotavirus was detected in one 18-month-old child. Astroviruses, caliciviruses, and adenoviruses were detected in 8.5%, 7.6%, and 2.5% of the hospitalized children, respectively. This, the first viral etiological study of childhood diarrhea in China, concludes that rotavirus G1-4 strains play an important role in severe diarrhea in Beijing children.

Immunity to mumps before and after MMR vaccination at 12 years of age in the first generation offered the two-dose immunization programme.

Sweden was the first country in the world to introduce a two-dose programme of vaccination against measles, mumps and rubella with a combined vaccine (MMR). It was commenced in 1982 and the vaccination was carried out at the ages of 18 months and 12 years. In 1992-93 the first age-group vaccinated at 18 months reached the age of 12 and accordingly received a second dose of MMR. A total of 382 children participated in the present study. Sero-immunity against mumps was studied by testing neutralizing antibodies using serial dilutions inoculated into cell cultures before and after the 12-year vaccination. Of the 229 children earlier vaccinated (group A), 27% lacked demonstrable antibodies before the booster. Of those without documented vaccination records (group B), 56% were seronegative before vaccination. After vaccination, 93% of group A and 86% of group B were seropositive (titre > or = 2). In the seronegative children, whether vaccinated earlier or not, the seroconversion was ca 75%. Previously unvaccinated children positive before vaccination and thus likely to be naturally immune had a higher mean-titre both before and after vaccination than the seropositive children earlier vaccinated. So far, the two-dose programme has proceeded as expected.