Here is another measles outbreak
in a 100% vaccinated population group, this time in India.
Jha N, Khan J, Prasad R, George K, Shrestha BK, Acharya B. Measles outbreak in a vaccinated population in Dhankutta. Nepal Med Coll J. 2003 Jun;5(1):16-7. Department of Community, medicine, B.P. Koirala Institute of health Sciences, Dharan, Nepal.
A measles outbreak occurred in Dhankutta town in year 2056 Falgun to 2057 Baishak (3 months). A total of 130 cases were registered at the Dhankutta District Hospital. A large proportion of the cases had severe disease with complications and were admitted at the hospital. None of the patients registered at the hospital died. Interestingly, 50.0% of cases were in higher age group (10 years and above) which is an unusual trend in developing countries. All the cases gave history of measles vaccination, which points towards the need for investigation of vaccine efficacy and cold chain efficiency.
Note the statement, "Interestingly, 50.0% of cases were in higher age group (10 years and above) which is an unusual trend in developing countries". The effect of measles vaccination in populations is to push the occurrence of the disease into an older age group. This has already taken place in developed countries and is well documented in the literature. Compared to natural immunity which is long term, the artificial immunity provided by vaccination is temporal and defers measles to a higher age range.