United States has 896 cases of new flu, CDC says

By Maggie Fox, Health and Science Editor

WASHINGTON (Reuters) - Outbreaks of the new H1N1 swine flu continue to spread across the United States, with 896 confirmed cases and more to come, the U.S. Centers for Disease Control and Prevention reported on Thursday.

U.S. officials have said they expect the swine influenza virus to spread to all 50 states and to cause many infections ranging from mild to severe.

Acting CDC Director Dr Richard Besser said the actual numbers matter less than the pattern of disease. "So far we are not seeing any signs of this petering out," Besser told reporters. "We are on the upswing."

And even though Mexican officials said they were over the worst, Besser said there was still significant transmission there, too.

"We are reporting 1,823 probable and confirmed cases in 44 states," Besser said. He has said that 99 percent of probable cases later turn out to be the new flu, so this is a good indication of how many true cases there are.

On Wednesday, the CDC had confirmed 642 U.S. cases of H1N1.

"Only about 10 percent of confirmed cases have a travel history for Mexico," he said. This suggests the virus is still passing very easily from one person to another.

The new virus looks very much like seasonal flu and it takes two rounds of tests to confirm a patient has the new H1N1 swine variety. Besser said the CDC was sending test kits out as quickly as possible and had filled requests for 78 countries, out of 131 who want them.