A new global flu pandemic within the next couple years is inevitable, one prominent flu vaccine manufacturer says.

Joseph Kim, head of Inovio Pharmaceuticals, which is currently working on a "universal" flu vaccine that would protect against most strains of the virus, says the world is due for a massive bird flu outbreak that could be much deadlier than the 2009 swine flu pandemic.

"I really believe we were lucky in 2009 [with the swine flu] because the strain that won out was not particularly lethal," he says. "Bird flu kills over 60 percent of people that it infects, regardless of health or age. It is a phenomenal killing machine—our only saving grace thus far is the virus has not yet jumped to humans."

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Fears about the possibility of an H5N1 avian flu pandemic first surfaced in the mid 2000s—since then, it has infected more than 600 people, killing more than 350 of them, mostly in southeast Asia. The global toll thus far has been mild because the disease can only be transmitted from bird to bird and from bird to human. But experts fear that a few simple mutations in the virus could make it transmissible from human to human.

Last year, Ron Fouchier, a dutch flu researcher, genetically modified a strain of H5N1 so that it was transmissible between ferrets, which are often used to test human-to-human transmissibility. At the time, Fouchier said he had created "probably one of the most dangerous viruses you can make." Paul Keim, a geneticist with the U.S. National Science Advisory Board for Biosecurity, echoed that sentiment: "I can't think of another pathogenic organism that is as scary as this one," he said. "I don't think anthrax is scary at all compared to this."

The discovery led the World Health Organization to call for a moratorium on laboratory-modified H5N1 research and recognize "that research on naturally-occurring H5N1 influenza virus must continue to protect public health."

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Kim says that if a deadlier version of H5N1 is going to emerge naturally, it will probably come from southeast Asia, where there are large pig, human, and bird populations. If a pandemic were to occur, the virus would likely be passed from birds to pigs, where it would mutate, and then from pigs to humans, he says.

"If I was a betting man, I'd say Southeast Asia," he says. "The last few pandemics have come from that area—you have a huge pig population, a humid climate, and a proximity of many birds, ducks, and geese."

After the original emergence of H5N1 in the mid 2000s, governments worldwide began stockpiling bird flu vaccines—but there's no telling whether the vaccines would offer much protection against a mutated strain or not.

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"They made an H5N1 vaccine with a seasonal flu strategy. Out of thousands of viruses circulating, they chose three or four strains to try to protect against," he says. "They had to predict which H5N1 strain is going to be lethal to the world. You have a better chance of hitting the Powerball … if the virus mutates, those stockpiled vaccines may be useless."

Kim's company and others have been working on a universal flu vaccine, using a synthetic virus strain, that would offer some protection against all types of flu. In early human trials, Inovio's H5N1 and H1N1 (swine) flu vaccines have increased humans' immune responses against those viruses and have protected against some of the most deadly historical strains in history, including the 1918 Spanish flu and the 2009 swine flu.

"Right now we can protect against all the known viruses," he says. "So our probability of protecting against emerging strains is greater than what we're limited to now."

http://www.usnews.com/news/articles/2012/12/24/global-flu-pandemic-inevitable-expert-warns