The outbreak of avian flu in China has killed at least 22 people and infected more than 108—including a man in Taiwan who had traveled in the eastern Chinese city of Suzhou. For two months airline stocks have been buffeted and officials have raised concerns about a possible pandemic. So why does the American public seem so unconcerned?
There are some good and some bad reasons for the relatively blasé reaction. Most obvious is that the disease seems far away. In addition, talk of pandemics is often overblown. The 2009 swine flu was bad but nowhere near the disaster that some experts feared.
On the positive side, public health has made significant advances in dealing with flu. These suggest cause for optimism about this outbreak and possible future ones.
The first major improvement is in the cooperative posture of the Chinese government—a far cry from the unfortunate experience with the SARS virus a decade ago. Back then, Beijing kept outside organizations such as the World Health Organization in the dark about the outbreak, which ultimately infected 8,000 people and killed about 800.
SARS spread across the Pacific (to Canada) and cost the global economy as much as $50 billion. A quicker and more open Chinese response could have limited the outbreak.
This time, by contrast, China is sharing information with the World Health Organization, closely monitoring the disease and aggressively culling flocks of chickens that could be infected.
Not that we should all sing kumbaya. Shanghai, where this flu began, is a relatively open part of China, which may account for some of the government's new transparency. In addition, the current director-general of the World Health Organization is China's own Margaret Chan. Her successors may not be viewed as favorably by Beijing.
Another positive story has to do with vaccine development and production. Thanks in large part to a push for greater vaccine capacity during the Bush administration, the United States now has a more reliable annual supply of the regular flu vaccine. Researchers in the U.S. have also seen improvements in cell-based vaccine technology that can supplement and perhaps even supplant traditional egg-based vaccines—meaning that vaccine quantity wouldn't be limited by the supply of eggs and wouldn't risk harming people with food allergies.
Regarding this outbreak's particular strain (H7N9), Chinese authorities have shared the virus with international flu labs, and U.S. health officials are developing lab strains that would allow American manufacturers to produce large amounts of a vaccine if needed.
The U.S. Biomedical Advanced Research and Development Authority and Novartis NOVN.VX +0.14% have a partnership that enabled them to start creating a vaccine before H7N9 even left China, based on the posted genetic sequence. This virus is particularly concerning because the H7 strain is hard for vaccine makers to match (and this year's flu vaccine had a not atypical effectiveness rate of only 62%). Still, Americans are much better off than they were just a decade ago.
The third cause for optimism is that there have been no recorded cases of so-called sustained human-to-human transmissions, meaning the movement of the virus from a single infected person to more than one other person. That occurred with SARS but not in previous cases of avian flu. If it did, it would be the nightmare scenario for public-health officials.
We aren't out of the woods just yet. While China has been tracking severe cases, it is unknown whether any individuals are mildly affected—having few symptoms but still being contagious. A recent World Health Organization report revealed that 40% of those infected had no obvious interactions with poultry, but they must have been infected somehow. The source of those transmissions is unknown.
Because of the uncertainties about transmission, the difficulties in matching H7 strains, and concerns about asymptomatic transmitters, the H7N9 outbreak bears careful watching. But the global public-health system is far more capable of dealing with flu than it was 10 years ago. Here's hoping that the current outbreak doesn't spread and test the limits of this improved system.
» NIH: Clues in H7N9 Sequence Analysis