Measles is a highly contagious disease caused by a virus. Patients with measles present with fever and with a rash. The rash looks like small, red, flat spots over the body. The rash does not form blisters, nor is it itchy or painful. Other signs include cough, conjunctivitis (red eyes) and coryza (running nose). Complications of measles can include diarrhea, dehydration, brain infection (encephalitis), blindness and death. Complications are more serious in those who catch measles as young infants (under 2 years of age) and in children who are malnourished.