The worst measles outbreak in the United States in 25 years has spread to Oklahoma.
Federal health officials on Monday reported 41 new cases nationwide, raising the total number sickened this year to 880 people.
The U.S. Centers for Disease Control and Prevention reported a 4.9 per cent increase in the number of measles cases from May 10 to May 17 in an outbreak that has now reached 24 states.
The agency has been providing weekly updates every Monday.
The CDC said there had been one confirmed case of measles in Oklahoma.
CDC spokesman Jason McDonald said most of the new cases were in New York, with 21 cases recorded in New York City and nine in Rockland County.