Trotz Masernimpfungen können Erkrankungen auftreten und es kann auch durch eine geimpfte Personen eine Übertragung von Masern erfolgen

http://www.aerzteblatt.de/nachrichten/58347/Measles-Mary-Geimpfte-Person-uebertraegt-Masern

http://www.ncbi.nlm.nih.gov/pubmed/25155071
„This is the first report of measles transmission from a twice-vaccinated individual with documented secondary vaccine failure“

http://cid.oxfordjournals.org/content/early/2014/02/27/cid.ciu105.abstract

„a significant proportion of non-responder vaccinees was observed.“

http://www.ncbi.nlm.nih.gov/pubmed/25115114
„Failure of 31.4% of these infants to sero-convert post vaccination can be attributed partly to administration of sub-potent vaccines.

http://www.ncbi.nlm.nih.gov/pubmed/24825255
„Vaccine effectiveness was 76.6%“

http://www.ncbi.nlm.nih.gov/pubmed/24585562

„According to the cohort study, vaccine efficacy for one dose was 34% and was 67% for two doses.Vaccine effectiveness was lower than expected.“

http://www.ncbi.nlm.nih.gov/pubmed/25475656

http://www.praxiskuepper.de/wann-impfen—wann-nicht/expertenfortbildung-zum-thema/index.php

Encephalitis Caused by the Vaccine Strain of Measles Virus

Report of a case of measles inclusion-body encephalitis (MIBE) occurring in an apparently healthy 21-month-old boy 8.5 months after measles-mumps-rubella vaccination.

http://cid.oxfordjournals.org/content/29/4/855.full.pdf+html?sid=f73ebd0b-5290-457c-995e-41637d0e25e0

The capacity of measles vaccine viruses to cause severe neurological disease in immunocompetent individuals remains controversial.

Stratton KR,Howe CJ, Johnston RB, eds. Adverse events associated with childhood vaccines: evidence bearing on causality. Washington, DC: National Academy Press, 1994;118–86