Swine flu is now present in more than half of America's states with 226 confirmed infections in 30 states, and will probably cover the entire nation soon, US health authorities said Sunday.

There remains only one death in the United States so far, a Mexican toddler who was visiting relatives in Texas, the Centres for Disease Control and Prevention (CDC) said.

"Virtually all of the United States prob ably has this virus circulating now," Anne

Schuchat, the CDC's interim deputy director for science and public health, told reporters.

The CDC's tally Saturday had been 160 confirmed cases of the A(H1N1) virus in 21 US states.

"Part of this increase is just catching up on the testing and part of it is we do think this virus is fairly widespread," Schuchat said.

There were "several encouraging signs," she added, as Mexico reported that its most lethal outbreak might be levellingoff.

But Schuchat stressed: "We expect a number of additional states to confirm the virus in the days ahead."

In the CDC's latest tally, six US states had infections in the double digits: New York (63), Texas (40), California (26), Arizona (18), South Carolina (15) and Delaware (10).

Massachusetts and New Jersey had seven cases each. Colorado had four and half a dozen states had three cases each: Florida, Illinois, Indiana, Ohio, Virginia andWisconsin.

Connecticut, Kansas and Michigan