U.S. Swine Flu No Worse Than Seasonal Flu, Experts Say

Christine Dell'Amore
National Geographic News
April 29, 2009
In Washington, D.C., a record number of patients inundated area hospitals this week worried they had swine flu, the disease outbreak that first jumped from pigs to people in Mexico.

On the social-networking site Twitter, "swine flu" was mentioned once a second on April 27, according to a report by the media analysis group Nielsen Online.

And blog chatter on the respiratory disease—which has expanded to eight countries—has already surpassed by ten to one the number of discussions about the salmonella in peanut butter scare from earlier this year.

Of course, the U.S. swine flu outbreak is nothing to sneeze at: As of April 29, 91 people in the country had confirmed cases, according to the U.S. Centers for Disease Control and Prevention (CDC).

The first U.S. death occurred on April 27, when a two-year-old child succumbed to swine flu after travelling from Mexico to Houston for treatment.

About 36,000 people in the U.S. die annually from seasonal influenza, and more than 200,000 are hospitalized, according to the CDC. (Read swine flu facts and myths.)

But in the U.S., where most swine flu cases are mild, "it's a situation where we should be cautious but not panicky," said Susan Rehm, medical director for the National Foundation for Infectious Diseases.

"From what we understand so far, the severity doesn't seem to be much different than what it is in regular seasonal influenza," Rehm said.

Georges Benjamin, executive director of the American Public Health Association, added that "we're in a phase of hopeful waiting."

"The lesson of prior disasters in the U.S. and emergencies—[though] it's not a disaster yet—[is to] get on top of this very quickly."

Not a Pandemic

In pigs, swine flu is a respiratory disease caused by type A influenza. Though cases of pigs infecting humans are rare, human-to-human transmission can subsequently occur.

The swine flu strain, called H1N1, is passed on just like seasonal flu—mainly through coughing or sneezing of infected people.

The symptoms also mirror those of seasonal flu, including fever, cough, sore throat, body aches, headache, chills, and fatigue.

Though H1N1 isn't a pandemic—the World Health Organization has given it a threat level of five, its second highest rating—it's much too early to tell how severe the outbreak will be, said Ruth Karron, director of the Center for Immunization Research at the Johns Hopkins Bloomberg School of Public Health.

"There probably will be additional deaths reported. We do [also] have deaths from seasonal influenza, and I think it's important to bear that in mind," Karron said.

As is possibly the case with H1N1, the elderly and young are most at risk for dangerous flu complications.

(Test your infectious disease IQ.)

Novel Virus

Experts are most concerned about swine flu for three reasons, the public health association's Benjamin said.

For one, it's genetically novel from other viruses, meaning that people aren't resistant to it. The virus is also easily spread and has been very lethal in Mexico, where 159 people have died so far.

Even so, there are strategies to slow its progression, Benjamin said: Telling people to stay home if they develop flu-like symptoms, closing schools selectively, and practicing basic hygiene are all effective.

Johns Hopkins's Karron added that improved vaccine production capacity and antiviral drugs are available, unlike in previous pandemics.

"What's really important for people to understand is we have methods of mitigation," she said.

There are also better tools than ever before to diagnose and track the illness, the infectious disease foundation's Rehm added. For instance, local physicians are now armed with up-to-date information from government agencies.

"If it had to happen, we are as prepared as we can be," she said.

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