However, many other La Nina events have not seen novel flu strains spread around the world, they caution.

BBC: La Nina 'linked' to flu pandemics

Minnesota is the nation's third-largest pig farming state, and its health experts said Wednesday they would be calling the illness "H1N1 novel flu" going forward.

CNN: Inaccurate 'swine' flu label hurts industry, pork producers say

"In order not to have a negative effect on our industry, especially under this crisis situation, we decided to call it 'novel flu' from now on, " said Androulla Vassiliou, the European commissioner for health.

CNN: Inaccurate 'swine' flu label hurts industry, pork producers say

What makes this new version of the H3N2 flu virus different is that it has picked up a gene from the novel H1N1 flu virus that became a pandemic three years ago.

CNN: CDC: Increase seen in new swine flu strain

The announcement came after a meeting of the WHO's Emergency Committee, which has debated since April whether the spread of a novel H1N1 flu virus was fast and widespread enough to warrant a Phase 6 designation.

CNN: Swine flu 'not stoppable,' World Health Organization says

According to the Centers for Disease Control and Prevention, pregnancy puts Wolf at higher risk of complications for flu in general, and so far that also holds true for the novel 2009 H1N1 virus.

CNN: Surviving H1N1 -- with baby in belly

Morrison, battling the flu and sniffling through much of the afternoon, was promoting the paperback edition of her novel "Home, " published last year.

WSJ: Toni Morrison talks to Google about creativity