Measles is a highly contagious viral disease that can be serious, especially in children. It remains a leading cause of death among young children globally despite availability of a safe and effective vaccine. In 2008 there were over 20 million cases of measles worldwide and 164,000 measles deaths, mostly children under 5 years old. Measles is caused by a virus that spreads through the air via coughs and sneezes or direct contact with infected secretions. Common symptoms include fever, runny nose, cough, red eyes, and a red rash. Prevention through vaccination is the most effective way to control measles and protect public health.