Complications from measles are common. The measles virus suppresses the immune system, lowering the body’s ability to fight other infections.
Common complications include ear infections (7-9%), diarrhoea (8%), and pneumonia (1-6%). Pneumonia accounts for nearly two thirds of measles deaths.
One in 1000-2000 cases develop encephalitis (inflammation of the brain), of these 15% die and approximately one third are left with permanent brain damage.
One in 100,000 cases will, many years later, develop subacute sclerosing panencephalitis (SSPE, a degenerative brain disease). This condition is always fatal.
Other complications include immune thrombocytopenic purpura (ITP, affecting the blood clotting) and inflammation of the small airways in the lungs, heart, kidneys or liver.
The risk of complications and death are higher in children under 5 years and adults over 20 years of age.
Measles during pregnancy increases the risk of miscarriage and premature labour.
Anyone who has a weakness of their immune system is at greater risk of very serious disease. These people are often unable to be immunised and rely on protection from those around them being immunised.
Death occurs in approximately 1-3 in 1,000 reported cases of measles overall in western countries.