The US Centers for Disease Control and Prevention on Wednesday tallied the highest number of US measles cases since the disease was declared eliminated a quarter-century ago, just as a key Senate committee split the vote to advance President Donald Trump’s nominee to lead the public health agency.

Cases are rising in the U.S., but the CDC says most people who bring measles into the U.S. are unvaccinated residents who traveled internationally.

More people have contracted measles in the US so far this year than in any year in the last three decades. New data from Atlanta-based Centers for Disease Control and Prevention shows 1,288 infections this year through 38 states,

U.S. measles cases have hit a 33-year high, with 1,288 confirmed infections in 39 states, the Centers for Disease Control reported on Wednesday Why it matters: The case count as of July 8 has already passed the highest annual count since measles was declared eliminated in 2000.

After investigating 50 of those travelers, the CDC was able to determine that measles spread during air travel in at least one of those situations, the spokesperson said. That is usually based on connecting confirmed cases of measles among airline passengers sitting near each other.

The CDC says the U.S. has it its highest number of measles cases in decades. Texas Children's Dr. Amya Mitchell spoke with FOX 26's Melissa Wilson about the uptick, symptoms, and vaccinations.

While Illinois has had eight cases of the virus so far this year, at least 1,288 cases have been confirmed nationwide, the most in more than 30 years, according to the Centers for Disease Control and Prevention.