It was a year ago that the term H1N1 entered the American consciousness, stamped in 72-point tabloid type. In April 2009, researchers at the Centers for Disease Control and Prevention (CDC) discovered that two children in California had been infected with a new strain of influenza virus originally dubbed "swine flu" but eventually and more accurately known as H1N1 even as Mexican health officials grappled with major outbreaks of a new flulike illness. By the end of the month, with new cases popping up in New York City, Canada and Europe, officials had come to realize they had a global emergency on their hands.
On April 27, 2009, World Health Organization (WHO) director-general Margaret Chan announced that the agency would raise the global flu pandemic alert level from 4 to 5 the first concrete step toward acknowledging that the world was caught in the grip of its first new pandemic in more than four decades. "This virus has the potential to spread very widely," said Chan at the time.
Within weeks, the H1N1 virus was spreading around the world, and by June the WHO had raised the alert level again, officially declaring an influenza pandemic. Since most people had no immune protection against the H1N1 virus, which had been simmering in swine populations for years before jumping into human beings in Mexico, it spread rapidly.
U.S. cases piled up in late spring, and both the sick and the "worried well" flooded hospitals, taxing health care resources. Schools shut down, sometimes for weeks, to stem the spread of the disease, leaving millions of schoolchildren and their parents stranded at home. In other countries, the response was more severe: in Mexico, the government banned public gatherings; in China, travelers from affected regions who showed signs of flu were quarantined.
From the start, the vast majority of H1N1 cases seemed relatively mild, but officials still had to work to keep the population from panicking. "This is obviously a cause for concern," said President Barack Obama on April 27, 2009. "It's not a cause for alarm."
As it turned out, Obama was right almost painfully so. Pharmaceutical companies had crashed an H1N1-vaccine-production program, and governments around the world (including Washington) had drawn up hasty plans to fend off a potential "second wave" of H1N1, which they feared could turn the upcoming fall flu season into a public-health disaster.
Yet catastrophe never came, and the total U.S. death toll from H1N1 about 13,000 people over the past year was considerably smaller than the 36,000 people who are estimated to die each year from the regular, seasonal flu. Millions of doses of H1N1 vaccine expired unused on doctors' shelves, and health officials are now under fire for overhyping what eventually seemed like a harmless bug. So, was H1N1 much ado about nothing?