Also Thursday, vaccine manufacturers and other health experts met at the World Health Organization headquarters in Geneva, Switzerland, to plot potential strategies to combat the swine flu virus.
The AP reported that drug companies were ready to start producing a swine flu vaccine, but many questions remain. They include how many doses to produce, particularly in relation to needed doses of seasonal flu vaccine.
The expert group's recommendations will be forwarded to the WHO's director-general, Margaret Chan, who is expected to issue advice to vaccine manufacturers and the World Health Assembly next week, the AP said.
But at least one infectious-disease expert said it was a "foregone conclusion" that drug manufacturers would be told to proceed with a vaccine for swine flu, technically known as H1N1 flu.
"If we don't invest in an H1N1 (swine flu) vaccine, then possibly we could have a reappearance of this virus in a mild, moderate, or catastrophic form and we would have absolutely nothing," said Dr. David Fedson, a vaccine expert and former professor of medicine at the University of Virginia.
One factor complicating a decision is that most flu vaccine companies can only make limited amounts of both seasonal flu vaccine and pandemic vaccine, such as that needed for swine flu, and not at the same time. The producers also can't make large quantities of both types of vaccine because that would exceed manufacturing capacity, the AP said.
Testing has found that the swine flu virus remains susceptible to two common antiviral drugs, Tamiflu and Relenza, according to the U.S. Centers for Disease Control and Prevention.
On Thursday, the CDC was reporting 4,298 U.S. cases of swine flu in 47 states, and three deaths. For the most part, the infections continue to be mild -- similar to seasonal flu -- and recovery is fairly quick.
The World Health Or
All rights reserved