The contribution of single antigen measles, mumps and rubella vaccines to immunity to these infections in England and Wales.

Objective: To obtain information on the use of single antigen measles, mumps and rubella vaccines to improve estimates of population immunity and help predict outbreaks.
Design: We requested information from providers of single antigen vaccines and from the Medicine and Healthcare products Regulatory Agency on requests for importation of single antigen measles and mumps vaccines.
Setting: England and Wales.
Main Outcome Measures: Number of doses of single measles, mumps and rubella vaccine, by age of child (in months), year given and area of residence, and number of children who have received all three single vaccinations.
Results: Of 27 providers identified, 13 held single site clinics: nine were individual general practitioners and five held clinics at multiple sites. Data were received from 9/27 (33%) providers operating 40/74 (54%) clinic sites. We received information on 60 768 vaccinations administered by single vaccine providers and 269 917 doses requested for importation. For children born in 2001/2002, the minimum estimates for the proportion who received single measles vaccine are 1.7% in 2001 and 2.1% in 2002, with a reasonable maximum estimate of 5.6% over the 2 years. For single mumps vaccine, the minimum estimates are 0.3% in 2001 and 0.02% in 2002, with a maximum estimate of 4.0%.
Conclusion: The contribution of single vaccines to immunity is small in comparison to that of the combined measles, mumps and rubella vaccine (MMR). For recent birth cohorts this contribution could increase routine coverage for measles-containing vaccines by around 2%, still below the level of immunity required to sustain elimination.