Measles is a highly contagious virus that puzzled early physicians and alarmed communities who didn't understand how it was spread. This exhibit uses books from the Rare Book Room to show how our understanding of the disease has developed over centuries of caring for patients and trying to control epidemics. 

We now know that measles is caused by a virus in the Morbillivirus genus and is highly contagious. It spreads through the air where it remains infectious for up to 2 hours. It causes a fever and a rash that starts on the face and spreads down the body. The severity of the rash peaks with the fever. Common complications of measles include ear infections, diarrhea, and pneumonia. Today, about 1 in 1,000 people have serious complications, including encephalitis.