Texas and New Mexico on Tuesday reported an increase of 28 cases of measles in the last five days, bringing the total known infections to 256 in the two states since an outbreak began in late January.

Texas is now reporting 223 measles cases in the outbreak that began in Gaines County. There are dozens more cases in New Mexico, too.

Counties in California, New York and Maryland detected their first measles cases of the year. The CDC has warned travelers to be vigilant as spring break begins.