Measles rash on a child's back. Measles, also known as morbilli or rubeola, is a highly infectious airborne viral disease. It mainly affects children, but can occur at any age and the adult form is more severe. An attack usually gives lifelong immunity. After an incubation period (8- 15 days), flu-like symptoms develop, accompanied by fever. Four days later, a red rash appears that lasts 3-5 days. Complications include ear and chest infections, diarrhoea and vomiting. Recovery takes 2-4 weeks. Treatment includes drinking lots of fluids and rest. Vaccination against measles provides effective immunity.