June 17 (UPI) -- The number of measles cases in the United States this year rose to 1,044, the Center for Disease Control and Prevention said Monday.
The updated number showed an increase by 22 confirmed cases from the previous week's tally in 28 states.
The number of confirmed measles cases is the most in the United State since 1992 and since the disease was declared eliminated in the country in 2000.
Five areas, including Rockland County, N.Y., New York City, California's Butte County, and the states of Pennsylvania and Washington have reported outbreaks of measles, which indicates three or more confirmed cases.
"These outbreaks are linked to travelers who brought measles back from other countries such as Israel, Ukraine and the Philippines, where large measles outbreaks are occurring," the CDC said.
The majority of people who have contracted measles were unvaccinated and the disease can spread more quickly in groups of unvaccinated people.