It's Ba-ack! U.S. Sees Largest Number of Measles Cases in 15 Years

Even though it's been considered eliminated in the U.S. since 2000, the number of measles cases and outbreaks spiked last year, according to the CDC.

In 2011, there were 222 cases of measles in the U.S, the highest number reported in 15 years. That figure is triple the number of cases that were reported in 2009 and 2010.

About half of the 2011 cases developed during outbreaks, which are defined as at least three cases that can be linked to each other. In 2011, there were 17 measles outbreaks. (During the previous decade, the average was four per year.)

Ninety percent of the 2011 cases originated in other countries where measles is still endemic, such as France, Italy, Romania, Spain and Germany. The illness was then transmitted to others in the U.S. The majority of the infected were people who hadn't received the MMR vaccine.

The vaccine is recommended for all children ages 12 to 15 months, with a booster shot at age 4 to 6 years. Children who will be traveling abroad can receive the vaccine as young as 6 months. Adults can be vaccinated if they did not receive the vaccine when they were younger.

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