‘Moderately Severe,’ Flu Season in U.S.

The flu season in the U.S. is being labeled 'moderately severe'. This is an designation of increased urgency compared to a lull of "mild" flu seasons following the 2008-2009 H1N1 pandemic flu season.

This season's flu is particularly concerning because the circulating strain, H3N2, has been shown to be more deadly to the elderly and very young from the recent flu season in Australia. This is particularly concerning because the vaccine was shown to have only a 10% efficacy in Australia, and it is the same vaccine we are currently using against the same predominating strain.

This low efficacy is not primarily due to any significant shift or drift event in the circulating virus. It is actually due to drift in the vaccine virus that has accrued mutations not relevant to the human virus. This development has elicited new cries for a universal flu vaccine.

'Moderately Severe,' Flu Season in the U.S.

~Scarlett