Danger of swine flu is not what it is, but what it could become

The new H1N1 virus arrived in the United States six months ago Sept. 21, and still creates enough doubts that experts nationwide don't know whether it will stay mild or become serious.

"So far the virus isn't that dangerous. It's more the potential than the reality that we're worried about," said Dr. Giorgio Tarchini, an infectious disease specialist at Cleveland Clinic in Weston, Fla.

As the new bug circulates, health officials fear it may mix with others to create a new version that spreads faster or causes more deaths. For instance, the bird flu that appeared in Asia in 2006 kills most who get it but does not spread easily in humans. A bad scenario would be if that bird flu combined with the new, easily spread H1N1, said Virginia flu expert Richard Wenzel, past president of the International Society for Infectious Diseases.

The mild nature of swine flu hasn't stopped some people from reacting sharply. At least two high school football games in Palm Beach County were canceled. Some emergency room doctors report entire families of healthy people have demanded treatment when children get sick.

Such fears may get worse as the number of swine flu infections are expected to grow through fall. The virus is expected to be the prevalent strain this flu season. Only time will tell if such fears are justified.

Experts have seen key differences between swine flu and seasonal flu:

Number of cases: Health officials estimate more than a million Americans caught swine flu so far and millions more will likely get it this winter -- more than come down with seasonal flu.

Deaths: From all those infected, about 600 have died. That's a death rate half that of seasonal flu, which kills tens of thousands per year.

Hospitalizations: Rates in swine flu are 1 to 2 per 10,000 people, varying by age. That's about half the rate of seasonal flu in infants and seniors, but about the same or slightly higher for others.

Timing: The new virus took off and spread in spring and summer, breaking the normal pattern of flu going dormant in warm weather. That worries experts who fear it may signal H1N1 is especially strong.

Who gets it: People ages 4 to 25 have the highest rates of infection from swine flu; those over 65 have the lowest. That's opposite of seasonal flu, which mainly kills infants and seniors. Older folks may have partial immunity to the new flu from past exposures to a swine flu, but doctors worry there are other unknown reasons.

Who dies: The young get it, but the new virus mainly kills middle-aged sick people. Sixty-six of 87 deaths in Florida (26 of 36 in South Florida) were in ages 25 to 64. Almost 80 percent of the victims had an underlying illness like heart disease, lung disease and immune weakness, the state Department of Health said.

"They die from the complications that flu causes," said Dr. Larry Bush, an infectious disease expert in Atlantis. "Maybe they get some other infection at the same time and they can't fight it all off."

Unexplained cases: Dr. John Livengood, director of disease prevention at the Broward County Health Department, said he has looked at the eight deaths in the county and can't find much in common between them. Six were middle-aged men, one was a baby boy, one was 22. A couple had no explanation, he said, just healthy people who didn't recover.

Erika Dopazo has seen both sides of the new flu. At 25, the marketing assistant in South Beach had never had the flu until late July, when she developed a fever of 101 degrees with bad chest congestion, cough, chills, aches and nausea. The swine flu made her as sick as she has ever been, but she got some medication and was back to normal within a week.

Weeks later, one of her friends died at age 27 after a monthlong illness complicated by swine flu.

"It wasn't really that bad for me. But it can be," Dopazo said.

Flu expert Wenzel agreed: "This (flu) looks particularly unkind in that sense. (Some) people fighting for their lives in intensive care units are young people who have no underlying medical problem."

Some recent developments worry experts. A dozen cases of new flu were found to be resistant to Tamiflu, an antiviral drug that can lessen the severity.

Also, the World Health Organization this week said two dozen cases of swine flu were resistant to the vaccine. On the plus side, everyone who had the flu will be immune to getting it again.
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