April 24, 2009— -- A top federal health official said the government's concern over the swine flu outbreaks in the United States and Mexico has grown since Thursday -- and a handful of influenza experts worry the deadly, never-before-seen hybrid strain may spur a pandemic.
Dr. Richard Besser, acting director of the U.S. Centers for Disease Control and Prevention, said that health officials confirmed yet another U.S. case of swine flu in California today, bringing the total number of Americans infected with the disease to eight.
Though it is still too early to say for certain whether a swine flu pandemic is possible or likely, the cases, all of which have occurred in California and Texas, have aroused concerns among the public, Besser acknowledged.
"We are worried as well," he said. "Our concern has grown since yesterday in light of what we've come to know since then."
Thus far, the first seven Americans found to have contracted the new variant have recovered, which Thursday led health officials to urge calm while the investigation into the virus continued.
Dr. Anne Schuchat, director of the CDC's National Center for Immunization and Respiratory Diseases, had said during a Thursday afternoon press conference that the strain did not "[look] like a very severe influenza. ... We don't think this is time for major concern around the country."
The sentiments were echoed by Canada's Dr. Michael Gardam, director of infectious disease prevention and control at Ontario's public health agency, in a Thursday night interview with the Canadian Broadcasting Corporation. Moreover, the World Health Organization has not yet made a change to the pandemic threat level -- the established worldwide barometer for pandemic threat.
Still, Mexican officials reported that what is believed to be the same mutant strain of swine flu already has killed at least 16 people in Mexico, and possibly as many as 61.