Measles, mumps, rubella (MMR) vaccine is a live vaccine preparation containing 
attenuated strains of all 3 viruses. MMR vaccine is widely used throughout the 
world, with the US having the widest experience with the vaccine. In countries 
where the vaccine has been introduced successfully, significant reductions in 
all 3 diseases for which it is protective have occurred. The vaccine has been 
shown to be highly immunogenic, with seroconversion rates of 95 to 100% being 
achieved for each of the 3 component vaccines. This immunity appears to be 
long-lasting and may even be lifelong. Minor adverse effects may occur 
approximately 1 week after immunisation. Rarely, mumps vaccine-induced 
meningitis (milder than that associated with wild mumps virus) may occur, its 
frequency varying with the strain of attenuated mumps virus contained in any 
particular vaccine. Clinically, the vaccine is indicated for infants aged 
between 12 and 15 months, and should be administered by intramuscular or deep 
subcutaneous injection. A few specific contraindications exist, including a 
genuine hypersensitivity to eggs, and to the aminoglycoside antibiotics 
kanamycin and neomycin. An increasing number of countries are now adopting a 
2-stage MMR policy in an attempt to prevent epidemics among those who remain 
unprotected, and to move towards eventual disease eradication.