What organs are involved with measles?

The measles virus primarily affects the respiratory system. The initial symptoms of measles include a runny nose, cough, red and watery eyes, and fever. The virus can also spread to other organs and cause complications, such as pneumonia, encephalitis (inflammation of the brain), and subacute sclerosing panencephalitis (SSPE), a rare and fatal degenerative disease of the brain that can develop years after the initial measles infection.