According to Texas Department of State Health Services data, 22 new cases since Friday have raised the total number of measles cases in the state to 422.
Cases have been discovered in two new counties: Erath and Brown, which are east of the source of the outbreak in Gaines County.
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State health officials say 42 people have been hospitalized since the outbreak began.
Most of the cases are in patients under 18 years old.
The CDC says getting the MMR vaccine is the best way to protect yourself from measles.
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