A rash of cases in Colorado has led to the cancellation of a planned vacation to New York City for schoolchildren.
Colorado health officials say two people in the metro Denver area contracted measles while vacationing at a resort in Florida.
The state says they are the first confirmed cases in the United States of measles, and officials are urging parents to stay home until symptoms subside.
Officials in Colorado say the cases were reported Saturday and Sunday in Fort Collins, the state capital, and Fort Collins-Loveland, the city where the two cases were detected.
State health officials are warning that people should avoid public gatherings, work and play until symptoms appear and monitor their immunizations.
Officials in New York, New Jersey and California say they are seeing similar cases.CBS News’ David Dague, Lauren Fox and Lisa Binder contributed to this report.