It's believed the woman caught measles when she was in hospital, and she died because her immune system had been seriously compromised from too many pharmaceuticals.
Doctors at the hospital in Washington state, where she died, confirmed she had had the MMR vaccine when she was a child. One, Dr Jeanette Stehr-Green, also said on local TV that the woman had been taking medication that had interfered with her immune system, and made her more vulnerable to the measles virus.
The hospital has refused to reveal the age of the victim, but have said she was not elderly.
She was receiving hospital treatment for several health problems when she caught measles from another patient. As her symptoms worsened, she was taken to the University of Washington Medical Centre in Seattle, where she died from pneumonia due to measles last spring.
Doctors did not establish the cause of death until the autopsy was carried out, as the woman did not display any of the usual symptoms associated with measles, such as a rash.
No other patient developed the disease, and the hospital is confident the outbreak has been contained.
(Source: Daily Mail, July 3rd, 2015)