Chicago (CBS) — The Centers for Disease Control is monitoring cases of measles in 21 states, including Illinois.

From January 1 to July 14, 2018, 107 people from 21 states, including Arkansas, California, Connecticut, Florida, Illinois, Indiana, Kansas, Louisiana, Maryland, Michigan, Missouri, Nevada, New Jersey, New York, North Carolina, Oklahoma, Oregon, Pennsylvania, Tennessee, Texas, and Washington, and the District of Columbia were reported to have measles.

In 2017, 118 people were reported to have measles nationwide. It was 86 in 2016 and 188 cases were reported in 2015.

The U.S. had a record year for measles in 2014, with 667 cases reported to the CDC. It was the greatest number of measles cases the country had seen since the disease was eliminated in 2000.

According to the CDC, most who contracted measles were not vaccinated.

Measles is still common in other countries across Europe, Asia, the Pacific, and Africa.

The reasons for the increase, the CDC reported:

  • 2015: The United States experienced a large, multi-state measles outbreak linked to an amusement park in California. The outbreak likely started from a traveler who became infected overseas with measles, then visited the amusement park while infectious; however, no source was identified. Analysis by CDC scientists showed that the measles virus type in this outbreak (B3) was identical to the virus type that caused the large measles outbreak in the Philippines in 2014.
  • 2014: The U.S. experienced 23 measles outbreaks in 2014, including one large outbreak of 383 cases, occurring primarily among unvaccinated Amish communities in Ohio. Many of the cases in the U.S. in 2014 were associated with cases brought in from the Philippines, which experienced a large measles outbreak.

The CDC says symptoms generally appear about seven to 14 days after a person is infected and can begin with a high fever, cough runny nose and red, watery eyes. The symptoms are then followed by a rash that appears on a person’s face and then spreads downward to the neck, arms, legs and feet.