In this video, Dr. Joe Bresee, with CDC's Influenza Division, describes the
symptoms of swine flu and warning signs to look for that indicate the need
for urgent medical attention.
Swine Flu EpidemicIn January 1976, 19-year old U.S. Army Private David Lewis, stationed at Fort Dix, joined his platoon on a 50-mile hike through the New Jersey snow. Lewis didn't have to go; he was suffering from flu and had been confined to his quarters by his unit's medical officer. Thirteen miles into the hike, Lewis collapsed and died a short time later of pneumonia caused by influenza. Because Lewis was young, generally healthy and should not have succumbed to the common flu, his death set off a cascade of uncertainty that confused the scientists, panicked the government and eventually embittered a public made distrustful of authority by Vietnam and Watergate.
This past Sunday, Homeland Security Secretary Janet Napolitano left open the possibility of a mass immunization program for the current outbreak of swine flu. If that happens, the Obama administration has a lot to learn from the debacle set in motion by Private Lewis' ill-fated hike.
Lewis was a victim of swine flu, a form of influenza endemic to pig populations. Influenza is caused by a virus, a microorganism that is mostly dead and partially alive. The virus' genetic code, held inside a protein sheath, consists of several helices of RNA. The virus injects its RNA into a healthy cell, which causes the cell to stop its usual work and make more copies of the virus. RNA genes mutate easily; for this reason, each new flu season brings a slightly different form of the disease into the population. Most year-to-year mutations bring little change to the virus, but for some still unknown reason, influenza seems to undergo a significant genetic change every ten years or so.
This major mutation results in a radically new strain of flu, one that races through a population because few people are immune to it. The dangerous influenza epidemics of 1938, 1947, 1957 (60,000 dead in the U.S.) and 1968 (the dreaded Hong Kong flu) fit this pattern. It was believed that swine flu, a particularly deadly form of the virus, had a 60-year mutation cycle that brought on worldwide pandemics, killing millions of people. Both the 10- and 60-year cycles were due to converge in the mid 1970s; Lewis' death in 1976 was thought to be the first instance of a new, incredibly lethal type of flu.
Doctors from the Centers for Disease Control tested Private Lewis' blood, and determined that his immune system had developed antibodies to a strain of flu similar to the Spanish influenza of 1918. That particular strain of swine flu produced the worst human pandemic of the 20th century: 1 billion sick in every country of the world, at least 22 million dead in the space of a few months. If Lewis had been exposed to something like the 1918 flu virus, the world could be in for an extensive and lethal outbreak. CDC doctors, charged with protecting the U.S. from epidemics, began to worry.