Swine Flu Facts: Preparing for the Pandemic

Brian Handwerk
for National Geographic News
August 25, 2009
It's back-to-school time again, and this year there's a new bully on the block: swine flu, or H1N1.

The virus may infect up to half of the U.S. population this fall and winter and may lead to between 30,000 and 90,000 deaths, according to a new report released by a U.S. presidential advisory group.

By comparison, about 36,000 people die of seasonal flu in the United States each year, and several hundred thousand are hospitalized.

Because people do not have immunity to the strain, H1N1 "poses a serious health threat to the nation," the report said.

Already in the United States, between April 15 and July 24, 2009, more than 43,000 people have fallen ill with swine flu and 302 have died, according to the U.S. Centers for Disease Control and Prevention (CDC).

The virus has swept the globe during the Southern Hemisphere's winter, killing nearly 1,500 people.

The World Health Organization estimates that H1N1 could infect 1 of every 3 people before the pandemic runs its course—about two billion people worldwide.

The good news is that H1N1's effects are largely similar to those of seasonal flu, and most people who contract it recover without medical treatment.

Vaccine Delay

Vaccines may be one way to steer clear of H1N1—for those who are able to get them.

Production and distribution delays will set back the agency's vaccination time line, according to CDC spokesperson Tom Skinner.

Instead of 100 million doses expected for mid-October, only about 45 million will be ready by that date, with the rest following at a rate of 20 million doses a week until December.

That likely means that many people will be unable to acquire vaccines before the onset of cold weather and traditional flu season.

The seasonal flu vaccine will not offer protection against H1N1.

The CDC won't know the vaccine's effectiveness until clinical trials end in early September, but the agency is confident.

"When we have a virus that's a good match for the vaccine, and we have a good match, vaccines are effective in preventing influenza and effective in preventing the serious consequences that can lead to hospitalization," Skinner said.

Priority Groups

The CDC has also issued vaccination guidelines that give priority to pregnant women; caregivers for children under six months of age; health care and medical workers with direct patient contact; kids six months through four years of age; and children and young adults 5 through 18 with chronic medical conditions such as asthma, heart disease, kidney disease, or diabetes.

"Not only is this group of people at risk for serious complications from influenza, they also serve as spreaders of the flu as well," Skinner said.

One noticeable group is missing from the list—the elderly.

While seasonal flu is especially dangerous for the aged, the H1N1 strain has had a far greater impact on young people under 25 years of age.

Health officials believe that U.S. adults older than 60 may have acquired at least partial immunity to the strain from exposure to previous H1N1 viruses, which circulated in the United States in the first half of the 20th century.

Dodging the Virus

How can you best minimize your chances of catching H1N1? You've likely heard it before: Clean your hands often with soap and water or an alcohol-based hand sanitizer. Try not to touch your mouth or nose, which can spread germs.

To avoid passing the flu along always cover your mouth when you cough or sneeze—you can unknowingly infect others even before your own symptoms appear.

H1N1 sufferers report fever, cough, stuffy nose, sore throat, chills, exhaustion, and headache. Lab tests are the only way to confirm infection with the H1N1 strain and not another type of flu.

If you do get sick, experts urge, stay home for at least 24 hours after your fever is gone.

You won't need to invent an excuse for missed time at work or school. Authorities are urging employers and administrators to develop flexible plans to respond to widespread absenteeism if infections begin in earnest.

With the prospect of a tough flu season ahead, no one knows if the fast-spreading H1N1 will mutate into a far more dangerous form.

Scientists have seen no signs of this so far, but Skinner noted that even routine flu can put people at risk.

"All of the attention that's been given to this new strain really should serve as a reminder of how serious flu season is every year.

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