Health officials nationwide are monitoring the spread of measles across 21 states, including California, the Centers for Disease Control and Prevention announced. 

The CDC reports there have already been 107 cases reported so far this year; the majority were diagnosed in those who were not vaccinated. 

Officials say this year is on track to become one of the worst years for measles in the last decade. 

The CDC reported there were 118 cases in 2017, and 86 back in 2016. 

The last outbreak was in 2015 when 188 people contracted measles.

That outbreak was linked to Disneyland in Anaheim, where it is believed a traveler who contracted the virus overseas visited the theme park while infectious, according to the CDC.

How does one contract measles?

The CDC says measles are still common in countries including Europe, Asia, the Pacific, and Africa, so travelers can bring it into the U.S. 

Measles is an airborne virus that spreads through coughing and sneezing. Symptoms show up in 10 to 14 days after exposure and include a high fever, cough, runny nose, and red eyes followed by a rash that typically starts on the face and spreads to the rest of the body.

In addition to California, these are the 20 other states being monitored for a measles outbreak: 

  • Arkansas
  • Connecticut
  • California 
  • Florida
  • Illinois 
  • Indiana
  • Kansas
  • Louisiana
  • Maryland 
  • Michigan
  • Missouri
  • Nevada 
  • New Jersey
  • New York 
  • North Carolina 
  • Oklahoma
  • Oregon 
  • Pennsylvania
  • Tennessee
  • Texas
  • Washington
  • Washington, D.C. 

For more information on measles, click here.

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