Past epidemics have current import
Lessons bear social, medical implications
When it comes to epidemics, history can teach - or mislead.
In the winter of 1976, when more than 200 soldiers came down with a bad flu at Fort Dix, N.J., and one died, people around the country panicked. The Ford administration quickly responded to fears of a pandemic influenza - mindful of the flu that had swept the world and killed millions in 1918 - by vaccinating more than 40 million Americans, nearly a quarter of the population.
But the 1976 pandemic never happened. And the vaccine probably caused more than 500 people to suffer a neurological disorder that can result in paralysis. That cost the federal government millions of dollars in damages.
Past disease outbreaks can be instructive for public health officials responding to the strain of swine flu that has led to at least 148 deaths in Mexico City and 48 confirmed cases in the United States. But the nature of epidemics is that they are unpredictable, say several leading public health figures; drawing too many comparisons to past experience poses its own dangers.
"Each outbreak has to be evaluated on its own terms," said Dr. Harvey Fineberg, president of the Institute of Medicine, in a phone interview yesterday.
Unlike the 1976 swine flu cluster that never spread beyond Fort Dix, the current swine flu outbreak can spread quickly from person to person, he said, and it has already appeared in disparate locations. But, Fineberg added, the aftermath of the 1976 vaccination campaign holds a cautionary tale: "The big lesson is to prepare by developing the vaccine, but not to combine that decision with the decision to go ahead and use the vaccine."
In a conference call with reporters yesterday, Dr. Richard Besser, acting director of the Centers for Disease Control and Prevention, said researchers have begun developing a vaccine against the swine flu but do not plan to distribute it yet.
Some infectious disease specialists suspect the agency is being cautious because of what happened in 1976. "They are sheepish about it," said Dr. Marc Siegel, a professor at the New York University School of Medicine who has written books about pandemics. "It was almost assumed that it was going to be a massive pandemic without really noticing what rate of transmission, if any, there was."
Dr. Richard Wenzel, immediate past president of the International Society for Infectious Diseases, said the key to understanding the scope of the current outbreak will be knowing how efficiently the virus is transmitted and what mortality rate is associated with it - characteristics that are not yet clear for this virus.
The influenza of 1918 "was one of the worst epidemics we've had," he said, because the mortality rate was high.
By analyzing the 1918 flu pandemic, scientists have identified strategies that seemed to control the spread of the virus early on in communities, said Marc Lipsitch, a professor of epidemiology at the Harvard School of Public Health. One example is shutting down schools.
"People start to transmit the virus before they are sick," Lipsitch said, which means we should not just treat and isolate people who are sick.
History also offers lessons about how to deal with the social backlash associated with epidemics, said Naomi Rogers, a professor of the history of medicine at Yale School of Medicine. She said the 2003 SARS outbreak, which originated in China, triggered "an unbelievable hysteria around things Asian and things Chinese."
"I think there's a greater concerted political effort now to try to ameliorate irrational and dispel discriminatory fear," Rogers said.
Use of the word pandemic is likely to trigger more demand for vaccines than the regular flu season, said Dr. Louise M. Dembry, director of hospital epidemiology at Yale-New Haven Hospital.
"Thirty-five to forty thousand people die per year in the US from the regular flu," she said. "It's not that it's a benign disease even in regular times."
Bina Venkataraman can be reached at firstname.lastname@example.org.