Did 1918-19 Flu Pandemic Begin Earlier Than Thought?
Researchers suggest it appeared in NYC months before taking its colossal toll
MONDAY, July 25, 2005 (HealthDay News) -- Conventional wisdom holds that the 1918-1919 "Spanish flu" epidemic -- the deadliest of the 20th century -- first appeared in Kansas and then spread across the country and on to the rest of the world.
Now, researchers are offering an alternate theory: They say evidence suggests the flu was taking a deadly toll in New York City months before it emerged in the Midwest.
But don't rewrite the history books just yet. One influenza expert said the new findings are pure speculation. And it's not clear if anyone will ever be able to prove the new theory is correct.
Nonetheless, the report in this week's online issue of the Proceedings of the National Academy of Sciences raises questions about the Spanish flu epidemic, which continues to fascinate today thanks to the work of medical historians and documentary filmmakers -- and health experts who warn that the world is long overdue for another deadly pandemic.
While the full extent of the Spanish flu's killing power wasn't understood at the time, its effects are well known now: More than 600,000 people died in the United States alone, and the worldwide death toll may have topped 40 million -- more people than were killed during World War I.
Current research suggests that the earliest signs of the epidemic appeared in the spring of 1918 at a military installation called Ft. Riley in northeastern Kansas, prior to the full-fledged devastation of the autumn and winter months.
But what if there was evidence of the same flu virus spreading disease before that time? Researchers with the New York City Department of Health decided to explore that question by examining local mortality records.
For reasons that aren't entirely clear, major flu epidemics often strike young children first, then move on to the rest of the population, said research scientist and study co-author Donald Olson. One possible explanation, he said, is that older people have developed immunity to some strains of the flu and have a bit of protection against dangerous new types.
So Olson and colleagues checked to see if younger New York City residents were dying of the flu at unusually high numbers before the spring of 1918. And they were, the researchers found, with deaths spiking from December 1917 to April 1918.
"It was neither mild nor a spring wave," Olson said. "It was happening in winter, and upwards of 2,700 New Yorkers died of it, but it was largely ignored."
There's a big problem with the new theory, however. The researchers don't know if the deaths they uncovered were caused by the same flu virus that trigged the deadly pandemic. Genetic tests could resolve the issue, but it's been virtually impossible to find surviving bits of 87-year-old flu virus. Among other things, scientists have turned to bodies buried in the frozen Alaskan tundra in the search for influenza germs from the epidemic.
Even so, Olson said, the similar infection pattern -- hitting young people first -- suggests there was no difference between the virus that struck New York City in February 1918 and the one that soon after ravaged the world.
At least one specialist is skeptical of the new theory.
"The major problem is that they can't prove it," said Dr. Pascal James Imperato, director of the master of public health program at the State University of New York Downstate Medical Center, in Brooklyn. "It's very circumstantial. One could easily make the case that that earlier epidemic was due to a totally different virus."
What does this all mean today? "I don't see that it has any relevance," Imperato said.
But Olson thinks the study findings provide more evidence that flu epidemics don't suddenly appear. "There's a concern among many people that if a pandemic happens, it will happen, like an explosion, and there's nothing we can do," he said.
In fact, he added, epidemics take their time, giving health officials a chance to do something -- but only if they pick up on the warning signs that trouble is coming.
Get more details about the Spanish flu from Stanford University.