The pre-vaccination epidemiology of measles, mumps and rubella in Europe: implications for modelling studies

Data on the pre-vaccination patterns of infection for measles, mumps and ru bella are collated from a number of European countries in order to compare the epidemiology of the three viruses. Key epidemiological parameters, such as the age-specific force of infection and the basic reproduction number ( R-o) are estimated from case notification or serological data using standar d techniques. A method is described to compare force of infection estimates derived from serological data. Analysis suggests that the pre-vaccination patterns of measles and mumps infection in the different countries were sim ilar. In contrast, the epidemiology of rubella was highly variable between countries. This suggests that it may be acceptable to use parameter values estimated from other countries to model measles and mumps transmission, but that this approach to modelling rubella transmission requires more caution . Estimates of R-o depend on underlying mixing assumptions. Constraints wer e placed on R-o estimates by utilising knowledge of likely mixing patterns. The estimates for R-o were highest for measles, intermediate for mumps, an d generally lowest for rubella. Analysis of within- and between-age-group t ransmission rates suggested that mumps transmission tends to be more concen trated within young children than the other two viruses. The implications f or the design of immunization programmes are that mumps may be the easiest to control via infant immunization since it is predominantly transmitted be tween the very young and the variability in rubella epidemiology requires t hat careful consideration of the possible effects of vaccination options sh ould be made using local data when planning rubella immunization programmes .