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.
Broliden
K
K
Department of Clinical Virology, Swedish Institute for Infectious Disease Control, Stockholm, Sweden.
Abreu
E R
ER
Arneborn
M
M
Böttiger
M
M
D002648:Child; D005260:Female; D006801:Humans; D017589:Immunization Programs; D007115:Immunization Schedule; D007117:Immunization, Secondary; D008297:Male; D008458:Measles Vaccine / Q000008:administration & dosage* / Q000276:immunology; D022542:Measles-Mumps-Rubella Vaccine; D009107:Mumps / Q000276:immunology / Q000517:prevention & control*; D009108:Mumps Vaccine / Q000008:administration & dosage* / Q000276:immunology; D012411:Rubella Vaccine / Q000008:administration & dosage* / Q000276:immunology; D019213:Rubulavirus / Q000276:immunology*; D013548:Sweden; D017778:Vaccines, Combined / Q000008:administration & dosage / Q000276:immunology
D008458:Measles Vaccine; D022542:Measles-Mumps-Rubella Vaccine; D009108:Mumps Vaccine; D012411:Rubella Vaccine; D017778:Vaccines, Combined