An article in the Daily Beast asks: If this is flu season, why is no one getting sick? The commentary notes that while people should be “hacking and sneezing and aching” the Center for Disease Control and Prevention reports that the flu is at “relatively low” levels as of January 2012.

While it would be great to believe that public health preparation and flu shots have created this healthy climate, the Daily Beast notes that epidemics are “notoriously hard to predict and track.” While warm weather may be responsible, even matching global warming with a downtick in flu infections is suspect. The article notes that the 2009 pandemic was “brought to the U.S. by high school kids who spent their spring breaks south of the border.”  And among the most difficult strains of flu arrives in the warm climates of Southeast Asia.

As for flu shots, their value is also questioned in the piece: the writer cites a recent Rand survey shows that only about 40 percent of adults are vaccinated, far below that needed to produce ‘herd immunity’ to reduce flu rates.

So what is the answer to the nation’s health this season? The article concludes it’s a “dark secret of medicine and public health: We usually have no clue why something, good or bad, is happening.”