Measles : causative agent the measles virus belong to the genus morbillivirus which is a member of the family paramyxoviridae
Vaccines against measles : live attenuated measles vaccine was first introduced for widespread use in 1963 .The primary strategy has been to achieve a high level of immunity in early childhood via mass vaccination campaigns
Vaccine strains
All vaccine strains that are currently in use (except Leningrad-16) have been derived from Edmonston strain .
Measles virus strains being used to prepare vaccine Edmonston A,Edmonston B ,Enders, Schwarz ,and Edmonston –Zagreb .
Edmonston –Zagreb strain has been adapted for growth on human diploid cells (WI-38) thus not only attenuating it further but also making it suitable for better and large scale industrial production ,many studies have shown higher seroconversion rates with these vaccines in younger infants (4-6 months) even those with higher material antibodies titre this makes these vaccines superior to the already available vaccine using Edmonston or Schwarz strain .
Composition of vaccine
The minimum quantity of the vaccine virus that should be contained in one human dose is generally considered to be 1000 viral infection unit .the minimum dose has been set at 5000 infective units .the vaccine is available as freeze dried product with a diluents
Dose and route of administration
It is administered as a single dose of 0.5 ml either alone or incombination with rubella and mumps components which is inoculated either intramusculary or deep subcutaneously
Contraindications
a-acute febrile illness
b-within three weeks of administered of another live virus vaccine but may be administered simultaneously and at different site