Long time immunogenicity of measles vaccine in the vaccination era: an open question

After WHO European Region determined the 2005 - 2010 Strategic Plan for measles elimination, the number of reported measles cases in Europe fell dramatically. This decrease is related to the vaccination strategy carried out by European countries. This extensive immunization strategy changes the epidemiological patter and could influence the effectiveness and the long-time immunogenicity of the vaccine. To evaluate the long-time immunogenicity of the measles vaccine in the vaccination era, a pilot study among vaccinated blood donors in Apulia was designed. Of 174 enrolled patients, 93.7% presented an anti-measles IgG titre positive. Geometric Mean Titre (GMT) seems to increase by age (p = 0.001). The GMT seems to increase by age and this could be related to the exposition to natural boosters, that was more probable before the beginning of universal mass vaccination against measles. Future studies have to focus the correlation between GMT and age.