The measles outbreak in Texas may be over, but as vaccination rates continue to drop, officials caution 'I don’t think this is the end at all.' Denver airport has already announced an exposure.

Health officials warn of a second possible measles exposure at Denver International Airport. The out-of-state traveler passed through gates C50 and C51.

Measles symptoms include a fever, runny nose, red eyes, cough and a rash that typically starts on the face. Most people become contagious about four days before the rash appears, so they could inadvertently infect others while thinking they have a less serious disease.