Friday, October 21, 2005

H5N1 up to the minute

World Health Organization FAQ is a comprehensive resource. Thanks H5N1 blog. Come to think of it, that blog is also a wellspring of timely reporting.

The most comprehensive treatment of the subject I have read is the Laurie Garrett article in Foreign Affairs, July-August, 2005. It prints out to about ten pages or so, and makes for interesting reading. Among other things she offers this historical caveat:

In January 1976, 18-year-old Private David Lewis staggered his way through a forced march during basic training in a brutal New Jersey winter. By the time his unit returned to base at Fort Dix, Lewis was dying. He collapsed and did not respond to his sergeant's attempts at mouth-to-mouth resuscitation.

In subsequent weeks, U.S. Army and CDC scientists discovered that the virus that had killed Lewis was swine flu. Although no other soldiers at Fort Dix died, health officials panicked. F. David Matthews, then secretary of health, education, and welfare, promptly declared, "There is evidence there will be a major flu epidemic this coming fall. The indication is that we will see a return of the 1918 flu virus that is the most virulent form of flu. In 1918, a half million people died [in the United States]. The projections are that this virus will kill one million Americans in 1976."

At the time, it was widely believed that influenza appeared in cycles, with especially lethal forms surfacing at relatively predictable intervals. Since 1918-19, the United States had suffered through influenza pandemics in 1957-58 and 1968-69; the first caused 70,000 deaths and the second 34,000. In 1976, scientists believed the world was overdue for a more lethal cycle, and the apparent emergence of swine flu at Fort Dix seemed to signal that another wave had come. The leaders of the CDC and the Department of Health, Education, and Welfare (HEW) warned the White House that there was a reasonably high probability that a catastrophic flu pandemic was about to hit. But opinion was hardly unanimous, and many European and Australian health authorities scoffed at the Americans' concern. Unsure of how to gauge the threat, President Gerald Ford summoned the polio-fighting heroes Jonas Salk and Albert Sabin to Washington and found the long-time adversaries in remarkable accord: a flu pandemic might truly be on the way.

On March 24, 1976, Ford went on national television. "I have just concluded a meeting on a subject of vast importance to all Americans," he announced. "I have been advised that there is a very real possibility that unless we take effective counteractions, there could be an epidemic of this dangerous disease next fall and winter here in the United States. ... I am asking Congress to appropriate $135 million, prior to the April recess, for the production of sufficient vaccine to inoculate every man, woman, and child in the United States."

Vaccine producers immediately complained that they could not manufacture sufficient doses of vaccine in such haste without special liability protection. Congress responded, passing a law in April that made the government responsible for the companies' liability. When the campaign to vaccinate the U.S. population started four months later, there were almost immediate claims of side effects, including the neurologically debilitating Guillain Barré Syndrome. Most of the lawsuits -- with claims totaling $3.2 billion -- were settled or dismissed, but the U.S. government still ended up paying claimants around $90 million.

Swine flu, however, never appeared. The head of the CDC was asked to resign, and Congress never again considered assuming the liability of pharmaceutical companies during a potential epidemic. The experience weakened U.S. credibility in public health and helped undermine the stature of President Ford. Subsequently, an official assessment of what went wrong was performed for HEW by Dr. Harvey Fineberg, a Harvard professor who is currently president of the Institute of Medicine.

Fineberg concluded:"In this case the consequences of being wrong about an epidemic were so devastating in people's minds that it wasn't possible to focus properly on the issue of likelihood. Nobody could really estimate likelihood then, or now. The challenge in such circumstances is to be able to distinguish things so you can rationally talk about it. In 1976, some policymakers were simply overwhelmed by the consequences of being wrong. And at a higher level [in the White House] the two -- likelihood and consequence -- got meshed."

Fineberg's warnings are well worth remembering today, as scientists nervously consider H5N1 avian influenza in Asia. The consequences of a form of this virus that is transmittable from human to human, particularly if it retains its unprecedented virulence, would be disastrous. But what is the likelihood that such a virus will appear?

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