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Dept of Health

Answer

Mr. Hammond: To ask the Secretary of State for Health what seroconversion rates occur with MMR in relation to (a) measles, (b) mumps and (c) rubella after (i) the first (ii) the second dose. [153674] Yvette Cooper: Taking seroconversion to mean the percentage of children with detectable antibodies against that infection shortly after vaccination, the usual proportion of individuals with detectable antibodies after the first dose of measles mumps rubella (MMR) vaccine is as follows: Measles 95-99 per cent. Mumps 90-95 per cent. Rubella nearly 100 per cent. However, the proportion of children with detectable antibodies against infection declines over time so that just before the age of school entry the proportions are lower. The proportion of children with detectable antibodies some years after MMR correlates much better with the actual efficacy of the vaccines (that is the ability to protect against the disease) and is as follows: Measles around 90 per cent. Mumps around 85 per cent. Rubella around 99 per cent. The second dose of MMR vaccine, given just before school entry, boosts the proportions of children with detectable antibody for each of the three diseases to around 99 per cent. for measles and mumps and virtually 100 per cent. for rubella. Although antibody levels do decline after the second dose of MMR vaccine, the vaccine's clinical efficacy against each of the diseases after the second dose is 99-100 per cent. This shows the importance of children receiving both doses of MMR vaccine.

Secondary information

Type

Written question

Reference

153674; 365 c89W

Session

2000-01

Subjects

Children Disease control Vaccination MMR vaccine Measles Mumps

Contains statistics

Yes

Link

View this Written question on www.publications.parliament.uk