Measles vaccination
Measles vaccine is a live attenuated vaccine. The various features of measles vaccination are:
- All presently used measles vaccine are tissue culture vaccines – chick embryo cell or human diploid cell
- The vaccines are freeze dried and stored at low temperature (2-8 degree C)
- Age of administration
- Maternal antibodies are present till 9 months of age, so if given earlier the vaccine will be inactivated
- Soon after 9 months of age (maybe earlier), the child is susceptible to measles infection
- So in developing countries (with high risk of acquiring measles infection), vaccination is given at 9 months of age
- In case of a measles outbreak, the vaccination can be given earlier, but has to be repeated at 9 months of age as long as 4 weeks have elapsed since the last vaccination
- In developed countries (with low/no risk of acquiring measles infection), vaccination is given at 15 months of age to prevent inactivation of vaccine by persistent maternal antibodies
- The vaccine is administered subcutaneously (0.5ml) after reconstituting it
- The reconstituted vaccine is to be kept in ice and to be used in 1 hour
- Vaccination produces a mild measles like infection after 5-10 days in about 15-20 percent of children, but it is self limiting
- Immunity is attained within 11-12 days
- One dose give about 95% protection
- Vaccination of contacts within 3 days is protective as the incubation period of measles induced by vaccination is about 7 days (compared to 10 days for measles)
- Contraindications are pregnancy, steroid use and immunosuppressed states
- The vaccine produces very less complications. Toxic shock syndrome is an important complication, but it occurs due to defects in the vaccination program (as in using the reconstituted vaccine for more than one session)
