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Swine Flu Sickens 2 California Kids

CDC Believes Flu Was Contracted in Person-to-Person Spread


The CDC is withholding the name of the airline that flew the boy and his three companions from San Diego to Dallas on April 3.

Swine flu viruses don't normally infect humans. When they do, it's almost always because of contact with an infected pig. But neither child had any direct contact with pigs.

Moreover, the viruses recovered from the children are not like the swine flu viruses common among pigs. That raises the specter of human-to-human spread of the virus, Finelli says.

"This virus is different, very different from that circulating in pigs. That was a red flag," Finelli told WebMD and several other news organizations. "The other red flag is both cases appeared almost simultaneously, 100 miles apart. When we see two cases [of swine flu] without animal contact that occur simultaneously and they have a different virus [than in pigs], we are concerned."

What worries the CDC is that the two cases might signal the beginning of a flu pandemic with a virus new to humans. But CDC spokesman Tom Skinner notes that it's the CDC's job to be worried. Several things about the cases are reassuring:

  • Both cases were detected by routine flu surveillance.
  • Southern California has unusually excellent flu surveillance -- and there has not been a large number of flu cases from unusual flu strains.
  • The virus is the H1N1 strain of swine flu. There are human strains of H1N1, raising at least the possibility of cross-protection -- especially in adults.

Not reassuring is the finding that the new swine flu strain carries three genes from Eurasian swine flu bugs not known to be circulating in the U.S. The new strain apparently is a reassortant virus that assembled itself from the genes of at least two different swine flu viruses. It carries no human flu genes.

Swine flu last spurred headlines in 1976 when an outbreak of swine flu at Fort Dix, N.J., killed one healthy recruit, caused four cases of serious pneumonia, and spread to some 230 soldiers before it vanished.

It's still not clear where the 1976 virus came from or why it went away -- but it spurred widespread public alarm and a vaccination program that badly misfired before being terminated.

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