Measles itself likely won't kill many people. Hoever, measles can turn into subacute sclerosing panencephalitis later in life, which is very lethal.
Just a question... kind of playing the devil's advocate, but I think it's usually ignored by most people when talking about vaccination.
A similar disease called progressive multifocal leukoencephalopathy (PML) is due to an immunocompromised state. Patients with HIV and those taking certain medications with multiple sclerosis are at risk.