The Texas health department said on Friday that the number of measles cases in the state rose 20% since its last report three days ago, as experts warn they expect the

Measles cases in Texas rose to 400 as the U.S. total reached almost 500 amid the worsening outbreak, officials have said.

The number of cases has jumped 73 cases over a three-day period. State officials said their team focused on completing open investigations of measles this week.