Outside the United States, the measles virus is still very common. In 1980, before widespread vaccination, measles caused an estimated 2.6 million deaths each year. The virus is highly contagious and can spread rapidly in areas where people are not vaccinated. Worldwide, an estimated 20 million people get measles and 146,000 people die from the disease each year—that equals about 440 deaths every day or about 17 deaths every hour.
In the United States, widespread use of measles vaccine has led to a greater than 99% reduction in measles cases compared with the pre-vaccine era. Since 2000, when measles was declared eliminated from the U.S., the annual number of people reported to have measles ranged from a low of 37 people in 2004 to a high of 644 people in 2014. Most of these originated outside the country or were linked to a case that originated outside the country.
Immunization has had a major impact on reducing measles deaths. During 2000-2013, measles vaccination prevented an estimated 15.6 million deaths. Global measles deaths have decreased by 75% from an estimated 544,200 in 2000 to 145,700 in 2013.
Complications are more common in children under the age of 5, or adults over the age of 20. The most serious complications include blindness, encephalitis (an infection that causes brain swelling), severe diarrhea and related dehydration, ear infections, or severe respiratory infections such as pneumonia.
Unvaccinated young children are at highest risk of measles and its complications, including death. Unvaccinated pregnant women are also at risk. A measles infection is especially dangerous for a pregnant woman. If she gets measles, she can have a miscarriage, or her baby could be born with certain birth defects including blindness, deafness, mental retardation and heart defects.
The MMR vaccine protects about 99% of people against measles. It protects 95% of people against mumps and about 98% of people against rubella (German Measles). Mumps (below) causes parotitis, which is an inflammation of one or both parotid glands, the major salivary glands located on either side of the face (see photo of child with mumps below).