Nearly 5,000 new U.S. swine flu cases have been reported in the last week, due partly to its continuing spread in the Northeast.

The number of deaths rose from 27 to 45. That's according to the Centers for Disease Control and Prevention which released new figures Friday. There are nearly 18,000 probable and confirmed cases now, found in all 50 states, the District of Columbia and Puerto Rico.

The pandemic seems to be waning in many parts of the country. However, cases continue to spread in New England, New York and New Jersey.