The Texas health department reported 309 measles cases in the state on Friday, an increase of 30 cases from its previous count.
Cases in Gaines county, the center of the outbreak, rose to 211 from 191 as of March 18, the Texas Department of State Health Services said.
Hospitalizations rose to 40 from 36, the department said.
It classified 307 patients as "unvaccinated or unknown" compared to 277 patients on March 18.
In New Mexico, cases rose to 38 from 35 as of the latest update on March 18, including two cases in Eddy County and the rest in Lea County, which borders Gaines County.
The U.S. Centers for Disease Control and Prevention (CDC) has said the measles, mumps and rubella (MMR) vaccine is the most important tool for preventing measles.
