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.
Meanwhile, the AP reported Tuesday that the epidemic had crossed new borders, with the first cases confirmed in the Middle East and the Asia-Pacific region. Canada, Austria, New Zealand, Israel, Spain, Britain and Germany also have reported cases of swine flu sickness. Deaths reported so far have been limited to Mexico, and now the U.S.
On Tuesday, Cuba and then Argentina suspended flights to and from Mexico, becoming the first countries to impose a travel ban, even though the World Health Organization said such bans were ineffective, because the virus has already taken root in more than one country, the AP said.
In Mexico, meanwhile, the toll from the swine flu epidemic appeared to be stabilizing, health officials there said late Tuesday, with only seven more suspected deaths, CBS News reported.
The virus is suspected in 159 deaths and 2,498 illnesses across Mexico, said Health Secretary Jose Cordova, who called the death toll "more or less stable." He said only 1,311 suspected swine flu patients remain hospitalized, a sign that treatment works for people who get medical care quickly, the news network reported.
On Monday, U.S. officials said they were tightening their travel advisory to Mexico, recommending that all nonessential travel to that country be avoided.
Also Monday, the World Health Organization raised the alert level over swine flu from 3 to 4, two levels shy of declaring a pandemic. A level 4 alert means there is sustained human-to-human transmission of the virus causing outbreaks in at least one country.
The United States has stepped up checks of people entering the country by air, land and sea, looking for signs of infection, and the CDC plans to distribute "yellow cards at ports of entry," Besser said Monday.
"These will provide information on swine flu, so that people coming into the United States will have information about this outbreak -- what to do if they become sick, what things they can do to prevent the likelihood that they will become sick," he said.
He also said U.S. officials were questioning border visitors about their health, looking for signs of possible infection.
SOURCES: April 28, 2009, teleconference with Richard Besser, M.D., acting director of the U.S. Centers for Disease Control and Prevention; CBS News; Associated Press