U.S. Reports First Swine Flu Death

April 29 -- WEDNESDAY, April 29 (HealthDay News) -- A 23-month-old child in Texas has become the first U.S. fatality in the spreading swine flu outbreak, federal health officials said Wednesday morning.

Dr. Richard Besser, acting director of the U.S. Centers for Disease Control and Prevention, confirmed the death. No other details on the case were immediately available, according to network news reports.

During a press briefing Tuesday, Besser had said that the more than 60 cases of infection found in the United States so far continued to be mild, but more severe cases were expected, and "as we move forward, I fully expect we will see deaths."

The number of confirmed cases of swine flu in the United States continued to climb Tuesday, to 64, with all the bulk of the new cases coming from a New York City high school that had previously reported 18 cases of the infectious disease, Besser said.

"There are 64 confirmed cases in the United States in five states," Besser said during the Tuesday afternoon teleconference. "Forty-five in New York, one in Ohio, two in Kansas, six in Texas and 10 in California."

Besser said the incubation period for the U.S. cases is two to seven days, which, he said, "is typical for what you see with an influenza virus."

The majority of new cases in New York continued to come at St. Francis Preparatory School in Queens. Some students who have come down with the infection had been to Mexico -- believed to be the source of the outbreak -- during a spring break trip to Cancun, the Associated Press reported.

As with the previously tested strains of the never-before-seen swine flu virus, new testing found that the pathogen remains susceptible to the two common antiviral drugs Tamiflu and Relenza, according to an April 28 dispatch from the CDC's Morbidity and Mortality Weekly Report.

The new flu strain is a combination of pig, bird and human viruses, prompting worries from health officials that humans may have no natural immunity to the virus.