Measles rash on a child's back. Measles is a highly infectious viral disease spread through the air. Also called morbilli or rubeola, it mainly affects children, but can occur at any age. 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 taking paracetamol. Vaccination against measles provides effective immunity.