ATLANTA, Georgia (KETK) – The CDC is warning of a measles outbreak that has spread to 21 states, including Texas.

From January 1-July 14 of this year, 107 people were reported to have the disease. The majority of them were unvaccinated, according to the CDC.

The year 2018 is on pace to become one of the worst years for measles since 2014 when 667 contracted the airborne virus. The 2014 outbreak was the greatest number of cases since measles elimination was documented in the United States in 2000.

Measles is a highly contagious virus that spreads easily when it hits an unvaccinated population. The virus lives in the nose and throat mucus of an infected person and spreads to others through coughing and sneezing. 

The CDC says the virus can live for up to two hours in an airspace where the infected person coughed or sneezed. If other people breathe the contaminated air or touch the infected surface, then touch their eyes, noses, or mouths, they can become infected.

Measles is so contagious that if one person has it, 90 percent of the people close to that person who are not immune will also become infected.

Infected people are contagious from four days before through four days after the rash appears.

The disease typically starts with high fever, cough, runny nose and red, watery eyes. Two or three days after the symptoms begin, tiny white spots may appear inside the mouth.

Three to five days after symptoms begin, a rash breaks out, with small red spots that begin on the face and spread over the entire body. In some cases, the disease can cause brain swelling and become deadly.

The CDC says measles can be prevented with MMR vaccine, which children usually get between 12 and 15 months of age. A second dose is usually given between the ages of 4 and 6. The MMR vaccine is said to be 97 precent effective at preventing measles.

The states reporting measles outbreaks are: 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.

The District of Colombia also reported cases of the illness.