WASHINGTON President Barack Obama asked Congress on Tuesday for an additional $1.5 billion (1 billion pounds) to fight swine flu as the confirmed U.S. caseload jumped to 65 people in six states in what doctors fear may become a full pandemic.
Lawmakers convened an emergency hearing in Washington on the government's ability to respond to a more severe outbreak.
"With a new infectious agent you don't sit back and wait and hope for the best. You take bold steps, and then you pull back if you need to," Dr. Richard Besser, acting director of the Centres for Disease Control, told reporters.
The CDC total included 10 cases in California, 2 in Kansas, 45 in New York, one in Ohio and 6 in Texas. An additional case was reported by Indiana state authorities.
While the new flu strain has killed up to 159 people in Mexico, cases seen in the United States and elsewhere have been mild. CDC officials said only five U.S. cases have required hospitalisation, two of them in California, but they have said they expect more serious cases -- and possibly deaths -- as surveillance expands.
California Gov. Arnold Schwarzenegger declared a state of emergency over the outbreak, enabling deployment of funds and personnel to fight the disease. Federal officials declared a national public health emergency on Sunday.
Obama, in a letter to Congress, said the $1.5 billion would give the government "maximum flexibility" as it fights the disease, supplementing antiviral stockpiles, adding medical equipment and starting preparations for a vaccine.
As public health headlines gripped the country, former Kansas Governor Kathleen Sebelius was sworn in as U.S. health secretary in an Oval Office ceremony Obama attended just hours after the Senate confirmed her nomination.
"We wanted to swear her in right away because we've got a significant public health challenge that requires her immediate attention, and that is the H1N1 flu outbreak," Obama told reporters.
Republican critics had delayed confirming Sebelius because of her stance on abortion.
Analysts said the addition of Sebelius and the filling of other senior health vacancies would help Obama, who hopes to appear in control while trying not to generate panic.
"You're almost always going to basically deal with the possibility that there will be some other crisis that emerges just as you're juggling other balls. Obama seems ready to do that compared to other presidents," said Norm Ornstein, a political expert at the American Enterprise Institute.
On Capitol Hill, health officials told an emergency hearing the funding would be crucial if the flu virus spreads.
"In the face of these cutbacks and layoffs and vacancies, we don't even have the workforce we had two years ago," said Dr. Paul Jarris, executive director of the Association of State and Territorial Health Officials.
In California, Texas and New York City, authorities have ordered schools shut where students have tested positive for the swine flu virus.
Los Angeles County coroner's officials investigated the deaths of two men for links to the disease, but later ruled out one. Local health officials said they expected infections in Los Angeles and were already investigating two possible "flu clusters" at schools in the suburb of Santa Clarita.
In New York, most confirmed cases of infection were at a Queens private school where the virus has sickened 28 students.
Officials had said earlier as many as 100 students might have been ill, but Mayor Michael Bloomberg said on Tuesday officials have stopped testing more people because the symptoms are mild, with only two people going to the hospital.
"This is following the pattern of normal, seasonal influenza," Bloomberg told reporters at City Hall. "So far, nothing about the spread of swine flu has surprised us."
A University of Notre Dame student was the first confirmed flu case in Indiana, according to state and school officials.
There were few signs of panic across the country, although sales of flu medication and items like face masks were up in areas close to where cases have been confirmed. Some stores reported a run on disinfectants.
Schools stepped up cleaning efforts and posted fliers urging students to wash their hands and cover their mouths and noses when they coughed.
"Everyone's a little leery of anyone coughing. Even though the news makes it seem really, really bad, it doesn't seem like it's actually that much of a concern," said Aaron Armelin, 33, a telecommunications technician in Los Angeles.
Despite advice that no pigs have been affected by the virus, Ecuador joined a long list of countries putting bans on imports of some U.S. pigs and pork products, further worrying pork producers.
(Additional reporting by Dan Whitcomb, Steve Holland, Matt Bigg, Emily Chasen, Jason Szep, Dan Trotta, Toby Zakaria; Editing by Maggie Fox and Vicki Allen)